PSYCHIATRIC SERVICES o ps.psychiatryonline.org o August 2012 Vol. ... without depression differ by cause of death? Methods. We assessed risks of mortality ...
Brief Reports
Early Mortality and Years of Potential Life Lost Among Veterans Affairs Patients With Depression Marcia Valenstein, M.D. Erin M. Miller, M.S. Khairul Islam, Ph.D. Helen C. Kales, M.D.
Kara Zivin, Ph.D. Mark A. Ilgen, Ph.D. Paul Nelson Pfeiffer, M.D. Deborah E. Welsh, M.S. John McCarthy, Ph.D., M.P.H.
Objective: Substantial literature documents excess and early mortality among individuals with serious mental illness, but there are relatively few data about mortality and depression. Methods: During fiscal year 2007, data from the U.S. Department of Veterans Affairs and the National Death Index were used to calculate mean age of death and years of potential life lost (YPLL) associated with 13 causes of death among veterans with (N=701,659) or without (N=4,245,193) depression. Results: Compared with nondepressed patients, depressed patients died younger (71.1 versus 75.9) and had more YPLL (13.4 versus 10.2) as a result of both natural and unnatural causes. Depending on the Dr. Zivin, Dr. Ilgen, Dr. Pfeiffer, Ms. Welsh, Dr. McCarthy, Dr. Valenstein, Ms. Miller, and Dr. Kales are affiliated with the National Serious Mental Illness Treatment Research and Evaluation Center and the Health Services Research and Development Center for Clinical Management Research, U.S. Department of Veterans Affairs, North Campus Research Complex, 2800 Plymouth Rd., Bldg. 14, Ann Arbor, MI 48109 (e-mail: kzivin@ umich.edu). With the exception of Ms. Welsh, they are also with the Department of Psychiatry, University of Michigan Medical School, Ann Arbor, where Dr. Islam, currently with the Department of Mathematics at Eastern Michigan University, Ypsilanti, was affiliated at the time that this report was written.
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cause of death, depressed patients died between 2.5 and 8.7 years earlier and had 1.5 to 6.1 YPLL compared with nondepressed patients. Conclusions: These findings have important implications for clinical practice, given that improved quality of care may be needed to reduce early mortality among depressed VA patients. (Psychiatric Services 63:823–826, 2012; doi: 10.1176/appi.ps.2011 00317)
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esearchers have documented excess and early mortality among patients with mental illness, yet most studies were restricted to patient populations in psychiatric settings (1). Depression is a leading cause of morbidity worldwide (2) and is associated with mortality among older adults (3). However, whether depression is associated with premature mortality, and to specific causes of premature death, in the general adult population remains an unanswered question. Although users of U.S. Department of Veterans Affairs (VA) services are typically older, the VA is the largest health care provider for the 1.6 million younger veterans who have served in Operation Enduring Freedom (OEF), in Afghanistan, and Operation Iraqi Freedom (OIF) (4). In 2008, 17.4% of OEF/OIF VA patients were diagnosed as having depression, which was six times higher than in 2002; a majority of depressed veterans had comorbid diagnoses (4). Thirty-five percent of
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veterans who returned from deployment in 2003–2004 and used VA services during the following year accessed mental health services (5). Today many more veterans than in previous eras are utilizing VA health care, possibly because of policies that have broadened access to returning veterans. Therefore, although it is important to understand overall causes of mortality among VA patients, it could be particularly useful to understand causes of premature mortality as well. The goal of this study was to extend prior research on depression and mortality among veterans and to examine specific causes and timing of mortality in this population. We examined the years of potential life lost (YPLL) associated with 13 causes of death as well as all-cause mortality among VA patients with or without depression. We addressed two related questions. First, do the ages at death and YPLL differ among VA patients with or without depression? Second, do the ages at death and YPLL among VA patients with or without depression differ by cause of death?
Methods We assessed risks of mortality for all causes and for specific diseases and the mean age of death and YPLL among VA patients with or without a depression diagnosis. This study used national data from the VA Serious Mental Illness Treatment Resource and Evaluation Center (SMITREC) administrative data resources linked 823
Table 1
Characteristics of 4,946,852 Veterans Affairs (VA) patients with or without depression, fiscal year 2006
Characteristic Sex Male Female Race American Indian African American Asian or Pacific Islander White Unknown Multiracial Age 18–24 25–34 35–44 45–54 55–64 65–74 75–84 85 or older Charlson Comorbidity Index Score (M±SD)a Comorbidity Cancer Cerebrovascular disease Chronic obstructive pulmonary disorder Congestive heart failure Connective tissue or rheumatic disease Dementia Diabetes, uncomplicated Diabetes with complications HIV/AIDS Metastatic carcinoma Mild liver disease Moderate or severe liver disease Myocardial infarction Paraplegia or hemiplegia Peptic ulcer disease Peripheral vascular disease Renal disease Psychiatric comorbidity Anxiety disorder Alcohol abuse or dependence Bipolar disorder Drug abuse or dependence Posttraumatic stress disorder (PTSD) Schizophrenia Anxiety, bipolar disorder, PTSD, or schizophrenia Service-related disability OEF/OIF veteranb Region Northeast Upper Midwest West South Facility type VA medical center VA community-based outpatient clinic Small Medium Large Very large Other a b
Depression (N=701,659)
No depression (N=4,245,193)
N
%
N
%
630,004 71,655
89.8 10.2
3,899,265 345,928
91.9 8.1
5,343 99,566 9,614 508,190 72,013 6,933
.8 14.2 1.4 72.4 10.3 1.0
19,280 490,996 53,516 2,502,968 1,139,266 39,167
.5 11.6 1.3 59.0 26.8 .9
7,491 31,034 62,099 149,103 252,911 91,468 86,082 21,471
1.1 4.4 8.9 21.2 36.0 13.0 12.3 3.1
61,102 183,711 278,869 553,059 1,073,535 905,575 955,214 234,128
1.4 4.3 6.6 13.0 25.3 21.3 22.5 5.5
1.1±1.6
2.8±2.7 .9±1.4
2.2±2.4
53,802 48,731 125,661 37,374 9,778 13,334 165,533 40,024 5,467 3,513 34,590 2,815 17,421 8,197 11,402 39,436 25,760
7.7 7.0 17.9 5.3 1.4 1.9 23.6 5.7 .8 .5 4.9 .4 2.5 1.2 1.6 5.6 3.7
336,367 211,764 519,683 190,041 46,824 30,956 898,776 170,310 14,191 8,906 77,513 6,688 76,169 24,883 44,305 218,662 153,314
7.9 5.0 12.2 4.5 1.1 .7 21.2 4.0 .3 .2 1.8 .2 1.8 .6 1.0 5.2 3.6
133,771 94,538 36,322 70,913 166,619 22,390
19.1 13.5 5.2 10.1 23.8 3.2
135,678 143,022 56,500 76,080 177,592 70,967
3.2 3.4 1.3 1.8 4.2 1.7
294,352 313,196 24,055
42.0 44.6 3.4
389,978 830,571 141,711
9.2 36.5 3.3
140,250 165,868 140,433 255,108
20.0 23.6 20.0 36.4
918,909 1,002,979 813,750 1,509,555
21.7 23.6 19.2 35.6
502,500
71.6
3,055,305
72.0
92,158 423,288 282,700 385,897 5,845
2.2 10.0 6.7 9.1 .1
13,688 67,078 48,667 64,586 5,190
1.94 9.56 6.94 9.20 .74
Possible scores range from 1 to 17, with higher scores indicating more comorbidities. Operation Enduring Freedom/Operation Iraqi Freedom
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with National Death Index (NDI) data from the Centers for Disease Control and Prevention (CDC). SMITREC’s administrative data resources include extracts from the Veterans Health Administration National Patient Care Database and incorporate data for all veterans who used inpatient or outpatient health services at the VA (6). Specifically, these data include VA patient treatment files (PTF), bed census files, extended care files, and outpatient care files (OPC). The PTF and OPC data sets include demographic, diagnostic, and services utilization data. The NDI is considered the “gold standard” of U.S. mortality databases (7) and was established for medical research. Patients treated in the VA health system during fiscal year (FY) 2006 and who were alive at the beginning of FY 2007 were included in the study. We examined one-year mortality from the beginning to the end of FY 2007 for VA patients with or without depression during FY 2006. Patients with at least one inpatient or outpatient depression diagnosis (ICD-9 codes 293.83, 296.2, 296.3, 296.90, 296.99, 298.0, 300.4, 301.12, 309.0, 309.1, and 311) were included. To calculate YPLL, we divided the study cohort into age groups, as follows: 18–24, 25–34, 35–44, 45–54, 55– 64, 65–74, 75–84, and 85 and older. Second, by using CDC life tables for 2007, we identified remaining life expectancy for the midpoint of each age group (8). Finally, we calculated YPLL as age group midpoint + life expectancy – age of death. This method evaluates the impact of early mortality on an entire population, not just on those who died younger than a specified age (such as 65 or 75, which is commonly used in epidemiologic literature to represent premature death) (9). This method assumes that risk of death in future years is approximated by the age-specific rates of death from all causes during the past year. Previous research found that the proportion of YPLL attributable to individual causes more closely resembles cause-specific mortality when derived from the remaining-life-expectancy method than by YPLL before age 65 (9). Therefore, we calculated YPLL with the remaining-life-expectancy method as well as
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mean age of death for all VA patients with or without depression. We compared these two groups overall and by sex, race, age, comorbidity, and, given the unique nature of the VA patient population, connection with VA services (service-related disability) and service in OEF/OIF. Second, we identified mean age of death and YPLL by cause of death. Finally, we conducted sensitivity analyses to examine how comorbid psychiatric conditions (anxiety disorder, bipolar disorder, posttraumatic stress disorder, schizophrenia, or any of these four disorders) influenced the relationships between depression status and YPLL and age of death.
Results A total of 4,946,852 patients met study criteria, and 14.2% (N=701,659) had a depression diagnosis during FY 2006. In FY 2007, a total of 167,069 (3.4%) patients died. Table 1 shows the characteristics of the study population. Leading causes of death for all patients included heart disease (N=45,110, 27%), malignant neoplasms (N= 44,179, 27%), respiratory disease (N= 11,713, 7%), cerebrovascular disease (N=7,197, 4%), accidents (N=5,730, 3%), diabetes (N=5,598, 3%), nephritis (N=3,671, 2%), septicemia (N= 2,389, 1%) influenza (N=3,400, 2%), suicide (N=1,684, 1%), liver disease (N=2,106, 1%), and homicide (N=318,
patients with depression but not any of the other disorders. Finally, among people with no other comorbid psychiatric condition, people with depression died earlier and had more YPLL than those without depression.