Health-related Quality of Life after Acute Lung Injury - ATS Journals

Health-related Quality of Life after Acute Lung Injury CRAIG R. WEINERT, CYNTHIA R. GROSS, JAMES R. KANGAS, CARON L. BURY, and WILLIAM A. MARINELLI College of Pharmacy and School of Nursing; School of Medicine, University of Minnesota; and Hennepin County Medical Center, Minneapolis, Minnesota

Our study objective was to assess health-related quality of life in survivors of acute lung injury (ALI) and to supplement generic and disease-specific questionnaires with findings from a focus group of ALI survivors. Six patients participated in the focus group, which revealed patient concerns with amnesia, depressed mood, avoidance behaviors, and a prolonged recovery period. Using a cross-sectional study design, 24 patients completed a questionnaire 6 to 41 mo after their lung injury. A total of 43% of the patients with ALI met criteria for depression; 43% had self-reported significant functional limitations, although 39% had minimal or no limitations. Significant respiratory and psychologic symptoms were reported in a quarter to a third of patients. There were large decrements in all domains of the SF-36 (a generic health-related quality-of-life instrument) in our sample compared with norms previously established for the general population. In addition, our patients had similar physical difficulties compared with previously studied patients with chronic medical illnesses but had more deficits in the social functioning and mental health domains. We conclude that long after lung injury, survivors have significantly lower health-related quality of life than the general population and are likely to have pulmonary and psychologic symptoms. Weinert CR, Gross CR, Kangas JR, Bury CL, Marinelli WA. Health-related quality of life after acute lung injury. AM J RESPIR CRIT CARE MED 1997;156:1120–1128.

Although research into the recovery of lung function in survivors of acute lung injury (ALI) has been ongoing for more than 20 yr (1), only recently have investigators focused on aspects of recovery beyond that of symptoms and objectively measured lung function (2). By describing the consequences of lung injury solely with the statistics of mortality and lung function, clinicians risk minimizing a patient’s experience of large changes in their physical, emotional, and social wellbeing. Moreover, with the case-fatality rate declining (3), it is important to confirm that a reduction in case-fatality rate is not offset by a marked decrease in the quality of life (QOL) of survivors. In addition, by comparing post-ALI QOL to other more familiar illnesses, clinicians may improve their understanding about recovery and better communicate prognoses to patients and families. Although severe lung injury is a relatively uncommon condition with an incidence of approximately five to eight cases per 100,000 adults (4), it serves as a paradigm for critical care outcomes because it strikes relatively young people and has an often prolonged, uncertain, and resource-intensive course. Emerging from the disciplines of sociology and psychology, the concept of quality of life has taken a firm hold in the clini-

cal research arena. Although there is still controversy regarding QOL’s conceptual definition, selection of measurement instruments, and clinical applicability, there is growing consensus regarding the major components or domains of QOL as it pertains to health (5). Our definition of health-related QOL posits a core set of causally linked dimensions of health starting with biologic/physiologic variables and proceeding through symptoms, mental, physical, and social function, health perception, and quality of life (6). All of these dimensions have consequences for a person’s life as perceived and interpreted by that person; therefore, we have emphasized patient-reported QOL over objective quantification of functional status. Although many of these dimensions can be influenced by environmental, political, and financial characteristics, in this study we have not attempted to identify these as determinants of health-related QOL. The overall purpose of our research was to track temporal changes in QOL after ALI and to identify determinants and predictors of QOL. For this study, we assembled a battery of generic and pulmonary-specific QOL scales, conducted an ALI focus group to supplement this battery with ALI-specific items, and used this supplemented battery to survey ALI survivors cared for at three major teaching hospitals.

METHODS (Received in original form November 13, 1997 and in revised form March 7, 1997) Supported by Grant NIH SCOR P50HL50152. Correspondence and requests for reprints should be addressed to Craig Weinert, M.D., Division of Pulmonary, Allergy and Critical Care Medicine, Box 276, 420 Delaware St. SE, Minneapolis, MN 55455. Am J Respir Crit Care Med Vol. 156. pp. 1120–1128, 1997

This study is composed of two parts. First, we conducted telephone interviews with ALI survivors and held a focus group to elicit patient concerns related to ALI. These concerns were added as questionnaire items to a core battery of QOL instruments. Second, we conducted a cross-sectional survey of ALI survivors using this supplemented questionnaire. The aims of the survey were (1) to quantify symptoms and

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Study Sites The University of Minnesota Hospital was the primary study site, while Hennepin County Medical Center and St. Paul–Ramsey Medical Center participated in patient recruitment since October and November 1995, respectively.

Study Population ALI cases are defined as having acute respiratory failure with the clinical picture of bilateral noncardiogenic pulmonary edema appearing after a clinical risk factor for lung injury. Because our study was not intended to examine pathophysiologic processes, we wanted the study population to be as inclusive of ALI as possible. We modified the criteria for the definition of acute respiratory distress syndrome (ARDS) from that of the American-European Consensus Conference (7) by including patients with PaO2/FIO2 ratios . 200. The Lung Injury Score (LIS) calculated by the method of Murray and Matthay (8) on Day 1 of ALI could range from mild (, 1.49) to severe (. 2.5), although subsequent days’ scores may be higher or lower. Two patients had LIS , 1.49 on Day 1. Excluded were patients under 18 yr of age, recent transplant recipients, and patients with clinically significant prior lung disease. If congestive heart failure, atelectasis, or pulmonary vascular disease was felt to be a major cause of the respiratory impairment, the patient was excluded. Right heart catheterization was not required for study inclusion. Follow-up time was dated from the first day when the patient met the inclusion criteria. This starting point was chosen rather than the day of extubation or ICU discharge because information regarding QOL would be most clinically useful while the patient still requires ventilatory support and it allows us to mark the onset of the lung injury and the antecedent risk factor (e.g., sepsis, trauma, or pneumonia) at nearly the same time.

review. Questionnaires were sent to the 34 survivors and 24 were returned, for a response rate of 71%. Five of the six participants in the focus group completed questionnaires. Twenty-one persons invited to the focus group and 13 of the 24 who returned questionnaires had brief telephone interviews. There was at least a 3-mo interval between the telephone interview and the mailed questionnaire. Reasons for nonresponse were five refusals but known alive and living at home and five not returned, unable to be located, and vital status unknown. The time from onset of ALI to returning the questionnaire ranged from 6 to 41 mo, with a mean of 19 mo (median 5 15 mo and SD 5 10 mo). Six were returned between 6 and 12 mo after ALI, twelve between 12 and 24 mo, and six between 24 and 41 mo. Calculating time from the date of extubation rather than onset of ALI makes no change in the rank ordering of patients and only a minimal change in the time interval distribution. The age and ventilator time of the nonrespondent group was similar to the respondent group, but the nonresponders were more likely to be female (50% versus 33%) and cared for at Hennepin County Medical Center (50% versus 8.3%).

Focus Group Procedure Focus groups are a well-described method of obtaining data regarding participant’s attitudes, beliefs, and feelings about a topic of mutual interest (9). Originally developed by sociologists, these groups are being used with increasing frequency by medical researchers because the group interactions may yield more information than individual interviews. Our purpose in assembling a group was to understand ALI from a patient’s perspective in order to modify or supplement our QOL battery and to identify areas in recovery from ALI that have not been previously investigated. The questions posed to the group were “What do you remember about your ICU and recovery experience?” and “How is ARDS affecting you now?” The 2-h session was taperecorded and transcribed and then two of the authors (C.R.W. and C.R.G.) independently performed a content analysis to identify prominent themes.

Interview and Focus Group

QOL Survey

To identify individuals who might provide information about their experience with ALI, we obtained a list of patients discharged alive with a diagnosis of ALI at the University of Minnesota Hospital and Clinics between 1992 and 1994. A total of 21 of 27 survivors who had received a diagnosis of ALI more than 6 mo previously were able to be contacted, interviewed by telephone, and invited to a focus group. Seven agreed and six patients in addition to one spouse attended the focus group, which was led by a faculty member with experience in focus group moderation. The predominant reasons for nonattendance were scheduling difficulties and excessive travel time to the university and usually not because of self-reported poor health. The six focus group participants had received the diagnosis of ALI between 10 and 35 mo before the session, and four of the six had severe ALI with ventilator time . 50 d. Compared with the original sample of 27, the focus group was overrepresented by patients with more severe lung injury, as judged by their longer time on mechanical ventilation. However, both groups had a mean Day 1 LIS of 2.4.

Participants known to be alive at hospital discharge and at least 6 mo after the diagnosis of ALI were sent a cover letter explaining the study and the QOL questionnaire along with a consent form and a stamped return envelope. Reminder phone calls and a repeat mailing were sent to nonresponders. Questionnaires were checked for completeness and keyed into a SAS-PC database (SAS Institute Inc., Cary, NC). This study, including the focus group, was approved by the Committees on Use of Human Subjects in Research at all three institutions.

QOL Survey Patients with ALI were identified by a research nurse by prospective examination of intensive care unit (ICU) logs and communication with critical care fellows and staff at the University of Minnesota Hospital, Hennepin County Medical Center, and St. Paul–Ramsey Medical Center. After eligibility was established, written, informed consent was obtained (usually from family members). Preexisting medical conditions and daily clinical data were abstracted from the paper medical record and, at the University Hospital, from the EMTEK System 2000 bedside computer system. Variables included risk factor(s) for ALI as recorded by the participant’s physicians within the first 3 d of ALI, demographics, hemodynamic, respiratory, and laboratory values. Days of mechanical ventilation, length of ICU stay, discharge vital status, and 30-d mortality were also recorded. From January 1992 to July 1995, there were 69 eligible patients with ALI, of whom 32 died in the hospital and three died after discharge. The eligibility of the 11 patients who had ALI before prospective data collection was initiated in July 1994 was confirmed by chart

Measures of QOL The study questionnaire is of a modular form that combines a generic QOL core with disease- and symptom-specific scales, demographic information, and global life-satisfaction items.

Generic QOL Instrument The Medical Outcomes Study 36-item short-form health survey (SF36) was the primary health-related profile used in this study (10). It is a widely used questionnaire with good construct validity, responsiveness, and reliability (11). It is a health profile providing scores in eight domains, each measured by responses to groups of two to 10 items. The domains of physical and social functioning, role limitations because of emotional or physical problems, mental health, vitality, bodily pain, and general health perceptions are scored on a scale from 0 (worst) to 100 (best). The domains can be combined into mental and physical summary scales but there is no global score. The SF-36 was chosen over other generic QOL instruments because there have been a number of publications demonstrating its validity in different patient populations (12), and the profile allows comparison of ALI patient’s scores to other pulmonary and nonpulmonary patient samples. There are ageand sex-specific population norms (12); the SF-36 has superior responsiveness and less ceiling effect than other instruments (13); it is designed for self-completion in about 15 min but can also be telephoneadministered; and changes in scores can be interpreted by referring to common medical conditions. With the patients in this study, the Cronbach’s alpha reliability coefficient for the SF-36 multi-item scales ranged

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from 0.85 to 0.93. Alphas . 0.80 are generally considered evidence of good internal consistency for a scale.

Disease-specific Instruments To assess dyspnea, a short scale derived from the Epidemiological Standardization Project (14) was used which grades dyspnea by a yes/ no response to items that cause breathlessness from 1 5 “walking on the level or a slight hill” to 5 5 “breathless while dressing.” Norms have been established for a sample of nearly 1,000 men (14) with a mean age of 59 yr where 12.2% noted at least moderate breathlessness defined as selecting the response 2 5 “walking slower than other people your age because of breathlessness” or worse. Respiratory symptoms of cough, wheezing, and chest tightness in the last 4 wk were reported as yes/no; and, if yes, how much distress or emotional upset has the symptom caused graded on a 5-point scale (modified from Lough and colleagues) ranging from 1 5 “not at all” to 5 5 “extremely” (15). Two items added from the focus group were “Memory problems” and “Bad memories or dreams about your hospitalization.” To further assess the impact of symptoms, five items from Guyatt’s Chronic Respiratory Questionnaire relating to mastery were modified for self-report to ask about respiratory symptoms (cough, dyspnea) and how often in the previous 4 wk the patient had been embarrassed, panicked, upset, or scared by their symptoms scaled on a 7-point Likert scale ranging from 1 5 “all of the time” to 7 5 “none of the time” (16). From our focus group findings, we added the item “Did you avoid places or situations because it might make your breathing worse?” The CES-D scale for symptoms of depression was chosen because of its brevity, self-report capabilities, and wide use in patients with medical conditions. A score of 16 or greater identifies a person who has a high likelihood of having depression (17).

Global QOL Instruments To measure overall QOL, we used the life-satisfaction item from the Index of Well-Being (18). It is a single question, “How satisfied are you with your life as a whole these days?”, recorded on a 7-point scale from 1 5 “completely satisfied” to 7 5 “completely dissatisfied.” Using the same point scale, we asked “How satisfied are you with your health at this time?” Another global QOL indicator used in national surveys and attributed to Bradburn (19) is “Taking all things together, how happy would you say you are these days—very happy, pretty happy, not too happy?” The self-report version of the Karnofsky Performance Index is included and measures activity level and symptoms ranging from 1 5 “normal, no complaints, no evidence of disease” to 7 5 “disabled, requiring special care and assistance” and 8 5 “worse off than any of these statements suggest” (20). Respondents were instructed to mark on two visual analogue scales with 0 representing the worst imaginable health state and 100 the best imaginable health state. The first line was “my health state in a typical day in the month before ARDS” and the second line was “today my health state is.” A short section collected information on demographics, cigarette use, and employment, and an open-response section was provided specifically inquiring about what activities the respondent could not do now because of health problems that they were able to do before ARDS.

Statistical Methods Descriptive statistics (means, medians, proportions) were used to summarize data. Comparisons between patients grouped by time since ALI or time on mechanical ventilation were performed with nonparametric tests, such as the Mann-Whitney U, Kruskal-Wallis, chi-square, or Fisher exact test, depending on the level of the measurement and the number of groups being compared (21). Changes within patients, such as changes in perceived health prior to and after ALI were evaluated by using the paired t test. Patient’s SF-36 domain scores were compared with published norms (12). The norms for the U.S. population were adjusted for the age and sex distribution of the

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study patients. These scores were compared with the patient’s scores by two-tailed t tests. No adjustments were made for multiple comparisons; however, exact p values are provided and readers may apply a Bonferroni adjustment (divide alpha by 8) to the SF-36 domain score test results in lieu of the nominal 0.05 level.

RESULTS Focus Group

The interview guide divided the discussion into two parts: acute illness and recovery in the hospital or rehabilitation unit, and late recovery (. 6 mo after ARDS) up to the present time. Although our purpose was to gain information on laterecovery QOL issues, several participants raised concerns about acute illness problems that might have an impact on late recovery. Three of four patients requiring tracheotomy for prolonged mechanical ventilation were convinced, at the time, that the tracheotomy was a permanent intervention and that they would never talk again. Most intubated patients noted frustration because of their inability to talk and communicate their needs. Five of the six noted significant amnesia for most of the ICU stay. The amnesia was as long as 2 mo and even extended to after discharge from the ICU. This was also reported in the telephone interviews, where nine of 11 patients questioned about ICU recall said they had partial or complete lack of recall of intensive care. Depression was mentioned by five of six participants, although they emphasized different time intervals. Three noted depressed mood and frustration during the early recovery phase especially during rehabilitation. “All of a sudden you have all this structure . . . and you have to start dealing with everything and getting ready to get out of the hospital, all at once and on top of that you can’t do anything for yourself and you have to rely on everyone else.” Two others, then 12 and 14 mo after ALI, mentioned ongoing depression that they related to not being able to return to previous levels of work or physical activity and to persistent fatigue. Five patients reported that difficulty in understanding their illness was a major concern. In the early recovery period, patients tried to recount the time and event course of their illness by surreptitiously reading their hospital chart because they thought communication with their medical team and family was insufficient. “I had a hard time getting that information and a lot of answers and it wasn’t until reading all that stuff [medical records] that I realized and I had to ask what is ARDS? A lot of people, it seemed to me, they thought I didn’t need to know.” Later in recovery, some patients wanted to know more about ALI in general and noted a lack of information sources for the lay public. Another issue for late recovery was that progress back to an acceptable functional status was slow. Five of six noted that their overall condition was still improving more than a year after ARDS. Notably, pulmonary symptoms like dyspnea and cough were mentioned less frequently than symptoms of fatigue, depression, and memory difficulties. “One thing I find somewhat alarming is that when they measure my lung capacity it measures 80% which they consider normal so in a sense they’re telling me I’m fine now and there is nothing wrong with me. And yet I can’t do any of the things that I took for granted.” Finally, fear of recurrent illness or symptoms was mentioned by five participants. Responses ranged from avoidance of smoke or strong odors that might cause pulmonary symptoms to “I have an unbelievable fear of any kind of mold or mildew and I’m just terrified of basements or cleaning the refrigerator [because of fear that molds would cause recurrent lung injury].” These and other experiences and concerns are listed in Table 1.

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Weinert, Gross, Kangas, et al.: Quality of Life after Acute Lung Injury TABLE 1 ISSUES REPORTED BY THE FOCUS GROUP OF ALI SURVIVORS Noisy ICU Severe sleep disruption Hallucinations and paranoia Communication difficulties Fear of disconnection from the ventilator Amnesia for part or all of the time in the ICU Depressed mood Unexpectedly prolonged recovery period Disturbing dreams and memories about the ICU Avoiding situations (e.g., pumping gasoline) that may lead to pulmonary symptoms or recurrence of lung injury Difficulty conceptualizing ALI as an illness and lack of public information for patients Persistent memory problems Anger (complications, bad outcomes) Guilt (had chosen semi-elective surgery, large medical bills) Change in personality Marked change in the character of the patient’s laugh and singing voice

QOL Survey

Patient demographics, ALI risk factors, and severity of disease are shown in Table 2. Patient ages ranged from 20 to 71, and two-thirds were male. Fifty percent had their primary risk factor for ALI originating in the lung. Despite expanded entry criteria, the median time of 24 d of mechanical ventilation and mean LIS of 2.4 indicates that this sample had predominantly moderate to severe lung injury. There were only two patients with , 7 d of mechanical ventilation, including one supported by mask ventilation. There is no evidence for a change in severity of lung injury in our patient sample over time as there was no significant difference in the median ventilator time between the first group of 12 patients (by date of ALI) and the second 12 patients (p 5 0.79, Mann-Whitney U test). Surprisingly, 63% reported smoking cigarettes after ALI, with more than 50% smoking more than one-half pack per day. Although 13 of 24 (54%) stated that they were now able to work for pay, only six were working full- or part-time. Of the 13 patients working before ALI, seven returned to work and six noted they were not presently employed because of health problems. Table 3 compares the ALI patient’s SF-36 scores to two groups of patients with previously published scores. The first group is a sample of 2,474 noninstitutionalized adults randomly sampled in the National Survey of Functional Health Status, with the mean domain scores adjusted for the age and

TABLE 2 CHARACTERISTICS OF 24 ALI SURVIVORS Demographics* Age: yr, mean (SD) Sex: male, n (%) Marital status: married n (%) Education: some college or more, n (%) Risk factor for lung injury, n (%) Pneumonia/aspiration Sepsis Other (including trauma and pancreatitis) Severity-of-illness measures Mechanical ventilation: d, median (range) Lung Injury Score†: mean 6 SD (range)

40 (12) 16 (67) 7 (29) 10 (42) 12 (50) 5 (21) 7 (29) 24 (0–487) 2.4 6 0.54 (1.25–3.25)

* Demographic variables at time of questionnaire completion. † Lung Injury Score calculated by the method of Murray and Matthay (8) on the first day of appearance of noncardiogenic pulmonary edema. n 5 18. Six scores unavailable because of transfer from another hospital or insufficient data to calculate score.

sex distribution of the ALI patients (12). The ALI patients scored significantly lower in all eight domains of the SF-36 compared with the U.S. population. The second comparison group is a sample of 144 outpatients with serious, chronic medical conditions, including myocardial infarction survivors with angina or symptoms of congestive heart failure (CHF), hypertensive patients with CHF symptomatology or stroke, and patients with complicated or poorly controlled diabetes (11). The ALI patients had similar scores in six domains compared with the chronically ill patients, but our sample scored even lower in the Social Functioning and Mental Health domains. The eight SF-36 domain scores can be combined into two summary scores that measure predominantly a physical or mental component. Using a U.S. population sample, the scores are standardized to a mean of 50 and SD of 10 (22). Our sample had a physical component summary (PCS) score of 37.5 and a mental component summary (MCS) score of 44.5. There was no statistically significant difference in either the physical (p 5 0.08) or mental score (p 5 0.22) between patient groups divided at the median time since ALI to the completion of the questionnaire. Figure 1 shows the scores of the ALI patients and the two comparison groups after standardizing the means and assigning the U.S. population score a reference value of zero. The most severely reduced domains for the ALI patients were Physical Functioning (21.4 SD) and Role Physical (21.3 SD). Respiratory symptoms were commonly reported by ALI patients. Dyspnea with exertion of at least moderate severity was reported in 36%, which is a proportion three times greater than that of a sample of older, community-dwelling men (14). Table 4 demonstrates that in > 50% of those having symptoms of cough, chest tightness, or wheezing, the symptoms were perceived as moderately distressing or worse. Lung injury patients reported psychologic symptoms as frequently as pulmonary symptoms. Including the focus group– derived items of bad memories about the ICU experience and current memory problems, up to two thirds of symptomatic patients reported that the symptoms caused moderate, quite a bit of, or extreme distress. A significant minority (35%) felt embarrassed by coughing or heavy breathing, and 26% felt “upset or scared” because of dyspnea at least “some of the time” or more frequently (scores 1 to 4 out of 7) in the last 4 wk. However, 61% “felt confident they could deal with their illness” and 65% had “complete control of their breathing problems” at least some

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TABLE 3 SF-36 DOMAIN SCORES AFTER ALI COMPARED WITH U.S. POPULATION AND PATIENTS WITH CHRONIC MEDICAL ILLNESS Domain

Lung Injury Patients*

U.S. Population†

Difference‡

p Value§

Chronic Illnessi

Difference¶

p Value

Physical Functioning Role Physical Bodily Pain General Health Vitality Social Functioning Role Emotion Mental Health

55.2 (37.6) 41.7 (44.6) 52.8 (30.7) 50.6 (29.9) 48.1 (27.3) 56.8 (36.7) 61.1 (43.6) 61.7 (24.0)

88.0 (23.3) 85.3 (34.0) 76.6 (23.7) 74.2 (20.3) 62.6 (21.0) 84.8 (22.7) 82.8 (33.0) 75.3 (18.1)

22.8 43.6 23.8 23.6 14.5 28.0 21.7 13.6

0.0002 0.00008 0.001 0.0008 0.016 0.001 0.024 0.008

57.4 (28.1) 43.9 (39.7) 65.1 (24.7) 49.1 (21.6) 47.8 (21.8) 80.0 (24.4) 76.2 (37.3) 77.6 (15.8)

2.2 2.2 12.3 21.5 20.3 23.2 15.1 15.9

0.80 0.82 0.07 0.82 0.96 0.006 0.12 0.003

* n 5 24. Values are mean (SD). † n 5 2,474. Means are adjusted for the age and sex distribution of the lung injury sample to better compare our younger, disproportionately male sample to the reference U.S. population. We summed the reference population values for each lung injury patient’s age-sex strata and then divided by the total sample size of 24. The adjustment increased the physical functioning and role physical scores by 4; all other values increased by , 2.2. Because the SD of the adjusted mean is biased towards a small value, the unadjusted U.S. population SDs are retained for statistical testing. ‡ Adjusted U.S. population 2 lung injury patients. § All p values are calculated from two-sided t tests without adjustment for multiple comparisons. See text. i n 5 144. Values are not adjusted for age or sex because the distribution is not available in published form. ¶ Chronically ill 2 lung injury patients.

of the time or more (scores 1 to 4 out of 7). A total of 39% avoided places or situations at least some of the time or more because it might make their breathing worse. Table 5 summarizes scores on instruments assessing functional status, depression, and health and life satisfaction. In both health satisfaction and life satisfaction, the responses

(lower scores indicate more satisfaction) ranged over the entire scale, with the mean response near neutral. There was a trend towards a small improvement in life satisfaction (4.3 versus 3.2, p 5 0.08) and health satisfaction (4.5 versus 3.1, p 5 0.09) between groups divided at the median time (15 mo) after ALI. While these differences are not statistically significant, in

Figure 1. SF-36 domains scores standardized to the general U.S. population. Comparison of the SF-36 domain score for 24 lung injury patients (bottom solid line), 144 outpatients with chronic medical illnesses (middle dashed line), and the U.S. general population adjusted for age and sex (top solid line). All scores have been converted to Z scores (standard deviation units), with the adjusted U.S. general population at a reference value of zero. Z score 5 patient mean score 2 adjusted U.S. population mean score divided by U.S. population standard deviation. The eight domains are distinct; the appearance of the lines should not imply continuity between the domains but is presented in the form advocated by the instrument’s developers to facilitate visual comparison.

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Weinert, Gross, Kangas, et al.: Quality of Life after Acute Lung Injury TABLE 4 SYMPTOM FREQUENCY AND PERCEIVED IMPACT OF SYMPTOMS IN PATIENTS AFTER ALI*

Symptom Cough Chest tightness Wheezy Difficulty concentrating Fearful, anxious Memory problems Bad memories

Number (%) Reporting Symptoms†

Mean (SD) Impact Score in Those Reporting Symptoms‡

Number (%) Scoring Moderate or Worse in Those Reporting Symptoms§

13 (57) 10 (43) 9 (39) 13 (56) 12 (52) 14 (61) 11 (48)

2.7 (1.2) 2.5 (1.3) 2.6 (1.4) 3.1 (1.2) 3.1 (1.2) 3.4 (1.2) 2.8 (1.6)

8 (62) 5 (50) 5 (55) 7 (54) 7 (54) 9 (64) 6 (55)

* n 5 23. † Self-reported presence of symptoms within the last 4 wk. ‡ Impact score indicates “How upsetting has this symptom been to you?” in the previous 4 wk. Score ranges from 1 5 “not at all,” 2 5 “a little,” 3 5 “moderate,” 4 5 “quite a lot,” and 5 5 “extremely.” § Percent is the number of patients scoring 3, 4, or 5 divided by number reporting symptoms multiplied by 100.

this sample the power to detect a difference of these magnitudes is only about 40%. A total of 33% described themselves as “not too happy,” although 21% did say they were “very happy.” The same question asked of almost 20,000 Americans with approximately the same age and sex distribution as our sample showed quite different results: 12.6% “not too happy” and 33% “very happy” (23). On the CES-D scale, 43% scored above the cutoff value of 16, which indicates a strong likelihood of depression. There appeared to be improvement during recovery, as 73% of recent patients (, 15 mo since ALI) scored . 16 compared with 25% of later patients (p 5 0.04, Fisher exact test). The Karnofsky Index distribution was bimodal: 30% indicated they required occasional assistance and 39% reported no or minor symptoms of disease. Table 6 demonstrates the high correlation between the CES-D and the MCS, suggesting that the two different instruments are measuring similar psychologic constructs. Age was correlated only with the PCS (r 5 0.52). There was no significant correlation between any of the six indices or scales and length of time since ALI or days of mechanical ventilation.

Patients retrospectively rated their health state in the month before ARDS as 74 (SD 5 20) and their health state now as 63.9 (SD 5 27) on the visual analogue scales. This difference was not statistically significant (p 5 0.12). Seven patients indicated higher scores (range: 2 to 75) for their present health state compared with before ALI. Table 7 shows that about a third of our patients had minimal or no preexisting conditions before ALI and more than half of those noted a substantial worsening (. 20-point decline) in their health status after lung injury. However, two thirds of our patients had chronic conditions, of which only 13% had substantial worsening, 73% noted only mild changes (, 20-point change in either direction), and two had a substantial increase in heath status after ALI.

DISCUSSION This cross-sectional survey of 24 patients with ALI demonstrates that even at a median of 15 mo after the diagnosis of ALI, patients have significant decrements in many health-related QOL

TABLE 5 QUALITY OF LIFE, DEPRESSION, AND FUNCTIONAL STATUS INDICES AFTER ALI Life Satisfaction, mean (SD) 1 5 Completely satisfied 7 5 Completely dissatisfied Health Satisfaction*, mean (SD) 1 5 Completely satisfied 7 5 Completely dissatisfied Happiness Item, n (%) Very happy Pretty happy Not too happy CES-D*†, mean (SD) Karnofsky Index*‡, n (%) 1 5 Normal, no complaints, no signs of disease 2 5 Able to carry on normal activity, minor signs and symptoms of disease 3 5 Able to carry on normal activity with effort, some signs and symptoms of disease 4 5 Able to care for myself but unable to carry on normal activity or do active work 5 5 Requiring occasional assistance but able to care for most of my needs 6 5 Requiring considerable assistance and frequent medical care 7 5 Disabled; requiring special care and assistance

3.7 (1.5)

3.7 (1.9)

5 (21) 11 (46) 8 (33) 19.8 (15) 5 (22) 4 (17) 2 (9) 2 (9) 7 (30) 1 (4) 2 (9)

* n 5 23; all others, n 5 24. † Center for Epidemiologic Studies—Depression Score. ‡ Data presented in entirety because of significant asymmetry of the distribution. There were no responses to 8 5 “worse off than any of these statements suggest.”

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TABLE 6 CORRELATION MATRIX FOR SIX HEALTH AND QUALITY-OF-LIFE INSTRUMENTS AND LUNG INJURY PATIENT CHARACTERISTICS*

1. 2. 3. 4. 5. 6. 7. 8. 9.

Life Satisfaction Health Satisfaction Karnofsky Index PCS† MCS‡ CES-D§ Time since ALIi Days on ventilator Age

1

2

3

4

5

6

7

8

9

1.0 0.65 0.59 20.32 20.74 0.84 20.31 0.09 20.11

1.0 0.79 20.72 20.58 0.63 20.23 0.42 0.16

1.0 20.75 20.61 0.61 20.43 0.25 0.40

1.0 0.10 20.17 0.29 20.30 20.52

1.0 20.94 0.37 20.25 0.07

1.0 20.40 0.32 20.07

1.0 0.11 20.05

1.0 0.31

1.0

* Spearman rank correlation coefficient. Strength of the correlation can be divided into weak (0.1 < |r| , 0.3), moderate (0.3 < |r| , 0.5), or strong (|r| > 0.5). The square of r estimates the percentage of shared variance between the two variables. † PCS 5 Physical Component Summary score. ‡ MCS 5 Mental Component Summary score. § CES-D 5 Center for Epidemiologic Studies—Depression Scale. i Months since onset of ALI.

domains and, on average, have SF-36 profiles similar to outpatients with serious, chronic medical conditions. Patients also note frequent and occasionally distressing pulmonary and nonpulmonary symptoms. In addition, we have demonstrated that the focus group concerns of memory problems, bad dreams about the hospitalization, and avoidance behaviors can supplement generic QOL instruments with disease- and therapyspecific items. Although there was a self-selection bias for participation in the focus group, which had a majority of patients with severe lung injury, the findings are comparable to previous reports of the experiences of post-ICU and mechanically ventilated patients (24), where anxiety and frustration from the inability to communicate, amnesia, and sleeping difficulties are commonly reported. Complaints of pain were conspicuously absent in our focus group. Early recovery and anxiety temporally related to transfer from the ICU to rehabilitation or home is a complex phenomenon; the focus group participants emphasized the difficulty in expanding the single unambiguous goal of mere survival into the multiple goals of physical and mental rehabilitation and social and occupational reintegration. The focus group noted problems with disturbing memories and

dreams about their ICU experience and avoidance behaviors for situations that they felt may make them ill again. This was confirmed in a minority of questionnaire respondents and is consistent with post-traumatic stress disorder (PTSD) theory, whereby situations are avoided not always because of actual fear of recurrent illness but because symptoms may give rise to unpleasant memories of the ICU experience (25). Similarly, when Stoll and colleagues evaluated 44 ALI survivors for PTSD almost 2 yr after discharge from the ICU, they found that 23% had PTSD based on a standardized self-report scale derived from the American Psychiatric Association criteria for PTSD (26). There are many impediments to patient’s recovery of mental health after critical illness but our patients specifically noted a lack of information about their hospital course and a paucity of information about ALI in general. A “care gap” may exist between the critical care team and the patient’s home environment and primary physician and gives rise to testable hypotheses about the effect of focused educational intervention and psychosocial programs on health outcomes in survivors of critical illness. Prolonged amnesia and slowly resolving cognitive deficits may play a role in patient’s early re-

TABLE 7 CHANGE IN SELF-REPORTED HEALTH STATUS AFTER ALI BY PREEXISTING HEALTH CONDITIONS*†‡ Difference in Two 100-point Visual Analogue Scales

Healthy or Minimal Disease

. 20-point improvement after ALI

None

< 20-point increase or decrease after ALI

Healthy (viral pneumonia) Healthy (SAH-aspiration) Kallman’s (fungal pneumonia)

. 20-point worsening after ALI

Healthy (trauma§) Healthy (trauma§) Healthy (viral pneumonia) Mild COPD (pneumonia)

Significant Disease Alc (pancreatitis) CML (sepsis) Short bowel syndrome (sepsis) SLE (pneumonia) Alc (liver failure) Alc (hypothermia) Hip DJD (pneumonia§) Alc (aspiration) Scoliosis (aspiration§) Alc (aspiration) Scoliosis (sepsis§) Alc (pneumonia) Depression (pneumonia) Alc (pancreatitis§) Chronic lower back pain (sepsis§) Crohn’s disease (sepsis§)

Definition of abbreviations: SAH 5 subarachnoid hemorrhage; Kallman’s 5 Kallman’s syndrome, asymptomatic; COPD 5 chronic obstructive pulmonary disease; CML 5 chronic myelogenous leukemia; SLE 5 systemic lupus erythematosus; Alc 5 alcoholism (with or without liver disease); DJD 5 degenerative joint disease. * Difference between two 100-point visual analogue scales: (1) “health state in a typical day in the month before ARDS”; (2) “today my health state is.” † Pre-ALI medical conditions and antecedent risk factor for ALI: condition (risk factor). ‡ n 5 23. § Postoperative complication.

Weinert, Gross, Kangas, et al.: Quality of Life after Acute Lung Injury

covery and suggests the need for repetition in discussions with patients. Recently, Hopkins and coworkers reported preliminary data documenting deficits in concentration, memory, and attention that persist in 80% of ARDS patients 1 yr after lung injury (27). Health-related QOL as measured by the SF-36 showed important differences between recovering ALI patients and the general U.S. population and similarities to outpatients with serious chronic medical conditions. The Physical Functioning and Role Physical domains showed the greatest decrease compared with the U.S. population (age and sex adjusted). Another way of interpreting the physical changes in the ALI sample is to compare their score on the Physical Component Summary scale, where the Physical Functioning, Role Physical, Bodily Pain, and General Health domain scales predominate. Our lung injury patient’s PCS score of 37 is most comparable to a general population sample of 274 individuals 75 yr of age or older who had a score of 37.9 (22). The Mental Component Summary score is less severely reduced compared with the general population; however, two of the major components of the MCS (Social Functioning and Mental Health) were significantly reduced in ALI patients, on average, compared with outpatients with serious, chronic medical conditions. McHugh and associates examined in detail the longitudinal pulmonary function and health-related QOL in 20 ARDS patients at intervals for up to 1 yr after extubation (2). The age and sex distribution was similar to our study, although the sample of McHugh and associates had a higher proportion of trauma cases and a lower median ventilator time (16 versus 24 d) and measurements were taken at intervals after extubation rather than at time of diagnosis. They reported that the mean Sickness Impact Profile (SIP) score improved considerably 3 mo after extubation and had only a slight improvement at 6 and 12 mo. The mean score at 1 yr was 10 (28). Published SIP scores in the range of 6 to 12 include patients with angina pectoris, untreated hypothyroidism, Crohn’s disease, and chronic obstructive pulmonary disease with a median FEV1 of 42% of predicted (29). There was no association between the severity of lung injury and total SIP score at any time interval in their sample. They also reported scores on a novel extension of the SIP whereby patients were asked to judge whether difficulties in performing activities were due specifically to pulmonary impairment and showed that the lung-related SIP score was always lower (reflecting better health) than the total SIP score. They concluded that ARDS survivors have experienced a variety of injuries to other organ systems that may have long-term effects on daily function. We agree with this last conclusion: conditions that have a predisposition to lung injury (e.g., trauma with central nervous system injury or sepsis from iatrogenic or disease-associated immunosuppression) may have long-term consequences that overshadow all but the most severe cases of lung injury. Our data, although not longitudinal, confirm that even in a sample examined at a median of 15 mo after the onset of lung injury there remain significant decrements in health-related QOL for many patients. There is a trend however, for both physical and mental improvement over time. Ghio and colleagues surveyed 25 ARDS patients at 15 to 388 wk after onset of ARDS and reported that about half complained of cough, phlegm production, wheeze, or dyspnea. There was no association between the presence of symptoms and objective impairment in simultaneously obtained pulmonary function tests (30). Peters and coworkers (31), in another cross-sectional sample of patients 6 to 36 mo after ALI, reported that eight of 26 subjects noted dyspnea, three of which

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noted that dyspnea interfered with their lifestyle. Our data are in rough agreement with these two reports, although our data demonstrate the wide range in the perceived severity of the symptoms and that in about half of the symptomatic patients the respiratory complaint was perceived as moderate or worse. Complementing these findings, we show that psychologic symptoms are reported just as frequently as pulmonary symptoms and, when present, are perceived as moderate or worse in more than one half of the patients. Although we do not have a comparison group of post-ICU patients without ALI, our patients’ 61% prevalence of subjective memory complaints is much higher than a community sample aged 18 to 64 yr old where 16.1% had subjective memory complaints; half of these had objective confirmation of short-term memory loss. The investigators also reported an association between subjective memory complaints and psychiatric disorders, specifically depression and anxiety (32). Depressive symptoms are common after ALI as shown by the mean CES-D score of 19.8 and 43% of patients scoring above the cutoff value of 16. Although the CES-D was originally developed for use in community epidemiologic surveys, it has been shown to have good sensitivity and specificity for the diagnosis of depression in patients with medical conditions that may affect responses to items related to somatic complaints (33). We can compare the ALI sample to patients with recent nonaphasic strokes, where 30% had scores above 16 (33), or to a sample of outpatients older than 60 yr with an average of five chronic medical conditions who had a mean score of 8.4, with 15.8% scoring above 16 (34). Fortunately, the point prevalence of depression in our sample seems to diminish after a prolonged recovery time; future studies might investigate the effects of early antidepressant therapy in this population. Because happiness, health satisfaction, and life satisfaction are influenced by many determinants, they are difficult to interpret in this small sample. There was no significant correlation between either life or health satisfaction and age, time since ALI, or days of mechanical ventilation. Although life and health satisfaction were correlated with each other, the r2 was only 0.042, suggesting that the variance in life satisfaction is only partially explained by health. Also, the variance in life satisfaction was more completely explained by the CES-D score (r2 5 0.71) or the MCS (r2 5 0.55) rather than the PCS (r2 5 0.10), suggesting that in these patients psychosocial symptoms and limitations are more important correlates of overall life satisfaction than physical symptoms and limitations. The observation that seven patients retrospectively indicated that their health had improved after lung injury has been reported in another study of serious illness. The SUPPORT study of seriously ill adults showed that 30% of patients entering the study with multiple functional limitations had improved functional status 2 mo later (35). Lung injury is often preceded by chronic, serious medical illnesses that may persist after pulmonary function improves; if maximal therapeutic intervention is also directed at the underlying condition then patients may rate their present health more favorably after hospitalization for ALI. An alternative interpretation is that patient’s retrospective estimation of their pre–lung injury health status is influenced by both their present health status and the understanding that they have survived a life-threatening illness (36). Our data cannot establish to what extent lung injury alone is the cause for the reduction in our patient’s QOL. Chronic conditions, severity and reversibility of the acute illness and subsequent lung injury, and complications of prolonged intensive care are all likely contributors to health-

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related QOL outcome. It is also likely that there will be interaction between these variables: we would hypothesize that the late morbidity of ALI would be most apparent in either previously healthy patients or those with rapidly reversible risk factors for ALI. Finally, our study is limited by two main factors: the crosssectional study design and a relatively low number of eligible survivors despite collaboration among three teaching hospitals. Small numbers make it difficult to simultaneously control for important covariates and make statistical inferences underpowered. Also, it is difficult to assess changes in healthrelated QOL without having a pre-hospitalization baseline or a control group without lung injury. Despite these limitations, this study provides strong evidence that ALI survivors, long after their lung injury, have frequent and often distressing pulmonary and psychologic symptoms and have QOL profiles significantly worse than the general population. Acknowledgment : The writers wish to thank Patricia M. McGovern, R.N., Ph.D., School of Public Health, University of Minnesota for conducting the focus group; the American Lung Association, Minnesota chapter for the use of their conference room for the focus group session; and Peter Bitterman, M.D., for critical review of the manuscript.

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