Alimentary Pharmacology & Therapeutics
Irritable bowel syndrome and dyspepsia among women veterans: prevalence and association with psychological distress L. S. SAVAS*, , D. L. WHITE*,à,§,–, M. WIEMAN*,à, K. DACI§,–, S. FITZGERALD*, S. LADAY SMITH**, , G. TANàà, D. P. GRAHAMà,§§, J. A. CULLY*,à,§§,–– & H. B. EL-SERAG*,à,§,–
*Section of Health Services Research and Department of Family and Community Medicine, Baylor College of Medicine; àHouston Center for Quality of Care and Utilization Studies, Health Services Research and Development Service, Michael E. DeBakey Department of Veterans Affairs Medical Center; §Section of Gastroenterology, Baylor College of Medicine; –Section of Gastroenterology and **Omen Veterans Program, Michael E. DeBakey Department of Veterans Affairs Medical Center; Department of Anesthesiology and Physical Medicine and Rehabilitation, Baylor College of Medicine; ààAnesthesiology Care Line, Michael E. DeBakey Department of Veterans Affairs Medical Center; §§The Menninger Department of Psychiatry and Behaviour Sciences, Baylor College of Medicine; ––Veterans Affairs South Central Mental Illness Research, Education and Clinical Center, Houston, TX, USA Correspondence to: Dr H. B. El-Serag, Houston Center for Quality of Care and Utilization Studies, Houston VA Medical Center (152), Houston, TX 77030, USA. E-mail:
[email protected]
Publication data Submitted 28 March 2008 First decision 23 June 2008 Resubmitted 18 August 2008 Resubmitted 1 September 2008 Accepted 5 September 2008 Epub Accepted Article 9 September 2008
ª 2008 Blackwell Publishing Ltd No claim to original US government works doi:10.1111/j.1365-2036.2008.03847.x
SUMMARY Background The burden of functional GI disorders and their associations with psychological distress in women veterans is unclear. Aim To examine 1-year prevalence of irritable bowel syndrome (IBS) and dyspepsia symptoms and their associations with anxiety, depression and post-traumatic stress disorder (PTSD) among women veterans receiving primary care at a Veteran Affairs Medical Center Women’s Clinic. Methods Irritable bowel syndrome, dyspepsia and psychological distress were assessed using the validated self-administered Bowel Disorder Questionnaire, the Beck Depression and Anxiety Inventories, as well as the Mississippi Scale for Combat-Related Post-Traumatic Stress Disorder Questionnaire. Results We enrolled 248 women (84% participation rate). Ninety-three (38%) reported IBS and 51 (21%) dyspepsia symptoms. Women with IBS and dyspepsia reported higher mean scores of anxiety (IBS: 24 vs. 12, P < 0.0005 and dyspepsia: 26 vs. 12, P < 0.0005), depression (IBS: 22 vs. 11, P = 0.0005 and dyspepsia: 23 vs. 11, P < 0.0005) and PTSD (IBS: 87 vs. 69, P < 0.001 and dyspepsia: 86 vs. 69, P < 0.0005). Age- and ethnicityadjusted logistic regression analyses showed a 3- to 46-fold increase in odds of IBS and dyspepsia among women with anxiety, depression or PTSD. Conclusion Women veterans have high prevalence of IBS and dyspepsia symptoms, both of which are highly associated with presence of depression, anxiety and PTSD. Aliment Pharmacol Ther 29, 115–125
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INTRODUCTION Irritable bowel syndrome (IBS) and functional dyspepsia are common functional gastrointestinal (GI) disorders. IBS and dyspepsia prevalence rates vary according to diagnostic criteria and target population (e.g. community, primary care or specialty care patient populations), but tend to be more common in women than in men. In Western countries, the prevalence of IBS symptoms ranges from 5% to 27% in women and from 2% to 19% in men,1, 2 whereas the prevalence of dyspepsia symptoms, most of which are thought to be functional in origin, ranges from 12% to 38% in women and from 8% to 27% in men.3–5 A biopsychosocial model of illness has been used to explain connections between GI and emotional and cognitive functions in which functional GI disorders are conceptualized as dysfunction of brain–gut interactions.1, 6–11 In this model, stressful life events and psychological factors exacerbate IBS and dyspepsia symptoms,1, 12, 13 influence health care seeking behaviour1, 14, 15 and impact clinical outcomes,1, 6, 12 such as improvement in symptom intensity.13 Psychological distress and trauma are commonly reported in patients with functional GI disorders. For example, significant associations have been reported between IBS and increased psychological distress,16–19 including depression,16, 20–23 anxiety20, 23–27 and posttraumatic stress disorder (PTSD).28 Similar associations have been reported for dyspepsia in clinic-based studies.29, 30 Sexual and physical abuse is also more commonly reported among patients with functional GI disorders (40–53%) compared with organic GI disorders (10–37%).31–33 Psychological distress as well as trauma is also commonly reported among women veterans.34–37 Previous research highlights the considerable physical and mental illness burden among women veterans who use Veterans Affairs (VA) medical facilities.38 Women veterans report high rates of military sexual assault; for example, the reported prevalence of rape during military service ranges from 11% to 48%.39 Because of women veterans’ increased risk of experiencing psychological distress, we expect an excess burden of IBS and dyspepsia among women veteran VA users. The Department of Veterans Affairs’ Office of Policy and Planning estimates that in 2006, women comprised approximately 7% of the total veteran population (1 731 125 ⁄ 23 976 991) and by 2030 is projected to comprise 13% (2 002 971 ⁄ 15 155 603).40 Approximately
11% of all women veterans currently obtain some or all of their health care from the VA.39 Few studies have investigated prevalence of IBS or dyspepsia and their associations with common psychological disorders among women veterans.41, 42 We therefore conducted this cross-sectional study to examine the prevalence of IBS and dyspepsia symptoms among women veterans at the Women’s Clinic at the Michael E. DeBakey VA Medical Center in Houston, Texas. We also examined the association between IBS and dyspepsia, with depression, anxiety and PTSD symptoms. To our knowledge, this is the first study that examines prevalence of IBS and dyspepsia in relation to commonly associated factors of psychological distress among women veterans.
METHODS The sampling frame for this study consisted of women veterans scheduled for out-patient primary care at the Michael E. DeBakey VA Women’s Clinic. Overall, the female patient population at this clinic is 44% white and 47% black, and 25% are between 18 and 40 years of age. We obtained daily lists of patients routinely scheduled for primary care clinic. We included only women veterans (not family members of veterans) 18 years of age and older and scheduled for the primary care clinic. All eligible women were approached and introduced to the study at the time of their arrival at the clinic and asked to complete the study questionnaires provided by a female researcher who was not part of the clinical staff. Participants were given the opportunity to complete questionnaires at the clinic or return completed questionnaires in a prepaid envelope. We also manually reviewed the comprehensive and integrated electronic medical records of all participants in the study to identify any diagnosis or symptoms compatible with IBS for the 1-year time period before questionnaire administration as well as the 1-year time period after. Among those women veterans who fulfilled Bowel Disorder Questionnaire (BDQ) symptom-based criteria for IBS, we also examined their entire available medical record for either definitive or potential occurrence of any alternate organic explanations of these symptoms including inflammatory bowel disease, celiac sprue or GI malignancy. A sociodemographic questionnaire that included 11 items was used to ascertain age at the time questionnaire was completed, race ⁄ ethnicity, marital status and ª 2008 Blackwell Publishing Ltd, Aliment Pharmacol Ther 29, 115–125 No claim to original US government works
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educational attainment. In addition, we included the following widely used screening instruments: The Bowel Disorder Questionnaire is a validated and reliable questionnaire that was used to determine presence of IBS and dyspepsia symptoms during the past year. The BDQ includes 59 items, 46 of which help identify and quantify the type, frequency and severity of GI symptoms.43, 44 In a sample of 395 subjects (50% women; mean age, 51 years), the mean kappa statistic indicated a high reliability for all BDQ items (kappa = 0.78; range: 0.52–1.0) for retests conducted a second time (ranging from 24 h to 7 weeks).43 The BDQ also discriminated functional bowel disease from healthy controls with a sensitivity of 83% and a specificity of 76%.43 The Beck Depression Inventory – second edition (BDI-II) is a validated and reliable self-report questionnaire that was used to identify the existence and severity of depression symptoms during the past 2 weeks, based on diagnostic criteria in the Diagnostic and Statistical Manual of Mental Disorders, fourth edition. Each of its 21 items is rated on a four-point Likert scale from 0 (strongly agree) to 3 (strongly disagree). The BDI-II manual reports high internal consistency among 500 psychiatric out-patients (coefficient alpha = 0.92) and 120 college students (coefficient alpha = 0.93).45 High internal consistency has also been reported in a sample of 340 adult primary care patients (correlations ranged from 0.54 to 0.74).46 Among 220 African American primary care patients (52% women; ‡18 years of age), the BDI-II had high internal consistency (coefficient alpha = 0.90), sensitivity (88%), specificity (84%) and diagnostic accuracy (85%).47 Additionally, the BDI-II correlates well with psychological tests such as the Revised Hamilton Psychiatric Rating Scale for Depression (r = 0.71), the Beck Hopelessness Scale (r = 0.68) and the original BDI-IA (r = 0.93).45 For our study, depression was computed as a total of all items and then categorized according to recommended cutoff values for total scores: 0–13 to indicate none or minimal range depression, 14–19 to indicate mild depression, 20–28 to indicate moderate depression and 29–63 to indicate severe depression.45 The Beck Anxiety Inventory (BAI) is a validated and reliable self-report questionnaire that is used to assess common anxiety symptoms in the past week. Each of its 21 items is rated on a four-point Likert scale ranging from 0 (strongly agree) to 4 (strongly disagree). Anxiety was computed as a total of all items and then ª 2008 Blackwell Publishing Ltd, Aliment Pharmacol Ther 29, 115–125 No claim to original US government works
categorized according to recommended cutoff values for total scores: 0–7 to indicate minimal anxiety; 8–15 to indicate mild anxiety, 16–25 to indicate moderate anxiety and 26–63 to indicate severe anxiety.48, 49 Beck et al.48 analysed reliability and validity among 160 psychiatric out-patients, and reported a high internal consistency reliability (coefficient alpha = 0.92), as well as a high correlation (0.75) between 1week test–retest scores. The Mississippi Scale for Combat-Related PTSD Questionnaire (M-PTSD) is a validated and reliable selfreport questionnaire used to assess symptom severity of PTSD in combat veterans. Each of the 35 items is rated on a five-point Likert scale ranging from 1 (not at all true or never) to 4 (extremely true or very frequently). The scale range of PTSD symptom severity (35–175) is derived by summing all items. In a sample of 362 male Vietnam-era veterans seeking care from Vietnam Veteran Outreach Centers, high internal consistency was reported for the entire scale (coefficient alpha = 0.94).50 In a sample of 30 Vietnam combat veterans who were diagnosed with PTSD according to the DSM-III criteria, 30 noncombat Vietnam-era veterans receiving care for nonpsychotic problems and 32 Vietnam veterans with no history of psychological or psychiatric treatment, the PTSD group scored significantly higher on the Mississippi compared with the psychiatric group (P < 0.0001) and the psychiatric group scored marginally higher than the well adjusted group (P < 0.10).50 In this study, we define PTSD using the recommended diagnostic cutoff value of 107 to indicate PTSD is present. At this cutoff level, the Mississippi scale had a previously reported sensitivity of 93%.50 We defined IBS and dyspepsia based on selfreported symptoms during the 12 months prior to clinical presentation using the BDQ. A full listing of symptom-based diagnostic criteria (based on modified Rome II criteria) is listed in Table 1.
Analyses Sociodemographic characteristics and psychological distress were compared in different groups (either IBS or dyspepsia present vs. neither IBS nor dyspepsia present) using v2 statistics to test statistical significance for dichotomous and categorical variables and t-tests for continuous variables. We examined sociodemographic variables including age (ages £44 years, ‡45 years), race ⁄ ethnicity (black, white and Hispanic or other, including American Indian ⁄ Alaskan native
Pain more than 6 times in the past year And each of the following criteria below: Ache or pain is moderate, severe or very severe
Pain occurs below the navel OR different places in both the upper and lower belly Pain often improves by having a bowel movement And 1 or more of criteria below: 1 or more of criteria below: Often have more bowel movements when pain begins Bowel movement habit changed in the last year Often have looser bowel movements when pain begins Usual bowel movement pattern Usual bowel movement pattern in in the last year includes the last year includes constipation, constipation diarrhoea or alternating constipation and diarrhoea Usually 4 or less bowel movements Usually 4 or less bowel in a week OR 13 to 21 bowel movements in a week movements in a week Often less than 3 bowel movements Often less than 3 bowel each week movements each week And 1 or more of criteria below: Take something for constipation (e.g. bran, fibre, laxatives) Often more than 3 bowel movements each day
Q2
Q4
Q28
Q25
Q27
Q24
Q23
Q22
Q21
Q20
Q14
Q3
Recurrent abdominal pain or discom Meets criteria for IBS, and fort in the last year, associated with criteria below: the following criteria below:
IBS with any constipation
Q1
BDQ item IBS
Often more than 3 bowel movements each day
1 or more of criteria below: Often have more bowel movements when pain begins Bowel movement habit changed in the last year Often have looser bowel movements when pain begins Usual bowel movement pattern in the last year includes diarrhoea or alternating constipation and diarrhoea Usually 13 to 21 bowel movements in a week
Meets criteria for IBS, and criteria below:
IBS with any diarrhoea
Q7
Q4
Q2
Q1
BDQ item
Recurrent abdominal pain or discomfort in the last year, associated with the following criteria below: Pain more than 6 times in the past year And each of the following criteria below: Pain occurs above the navel OR different places in both the upper and lower belly Pain occurs once a week, several times a week OR daily
Dyspepsia
Table 1. Criteria for irritable bowel syndrome (IBS), IBS subtypes, and dyspepsia disorders: symptom identification using the Bowel Disorder Questionnaire
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Often urgent need to have a bowel movement Stools often hard After finishing a bowel movement, often still feel stool needs to be passed Q33
Q30 Q31 Q32
RESULTS
BDQ, Bowel Disorder Questionnaire.
Often strain to have a bowel movement
Often strain to have a bowel movement Often loose and watery stools Stools often hard After finishing a bowel movement, often still feel stool needs to be passed Often urgent need to have a bowel movement Q29
IBS BDQ item
Table 1. (Continued)
IBS with any constipation
IBS with any diarrhoea
Often loose and watery stools
BDQ item
Dyspepsia
ethnic groups), education (high school graduate or less, at least some college) and marital status (married, separated, divorced or widowed, and never married). Psychological distress variables were examined using previously presented cutoffs values for depression and anxiety scores (minimal, mild, moderate and severe)45, 49 and PTSD (present, absent).50 The Levene’s test was used to test for equality of variances between groups and if the criterion was not met (P < 0.05) we computed the t-tests for continuous variables assuming unequal variance. Linear-by-linear v2 tests for trend for categorical data were computed to examine the relationship between IBS and dyspepsia across levels of depression and anxiety. We examined the associations between IBS or dyspepsia (dependent variables) and psychological distress, including depression, anxiety and PTSD symptoms (independent variables) using logistic regression models. Depression, anxiety and PTSD were each modelled separately as continuous as well as categorized variables described above. For continuous variables, the parametric estimates reflect the degree of risk change associated with every one-point change in score. To account for possible confounding, we adjusted for age groups (£45 years, >45 years) and ethnicity groups (white, nonwhite). Another model included all psychiatric disorders (depression, anxiety and PTSD) simultaneously as continuous variables to adjust for coexisting psychiatric symptomatology. All analyses were conducted using SPSS version 15 (SPSS Inc., Chicago, IL, USA). The study was reviewed and approved by the Institutional Review Board for Human Subject Research at Baylor College of Medicine.
ª 2008 Blackwell Publishing Ltd, Aliment Pharmacol Ther 29, 115–125 No claim to original US government works
Between November 2005 and February 2006, we approached 296 women veterans potentially eligible to participate. Of these, 283 consented to participate and 248 completed the questionnaires, producing an overall participation rate of 84% (248 ⁄ 296). Among all participants, 40% were 45 years of age or less. Most self-identified as either black (48%) or white (41%), 9% identified as Hispanic and 2% as other ethnic groups. Twenty-eight per cent were married and 54% were previously married (divorced, separated or widowed) and most (72%) had some college education or less. Thirty-eight per cent (93 ⁄ 248) of participants reported symptoms consistent with a potential diagnosis of IBS
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(based on self-reported symptoms using the BDQ), most with diarrhoea features (92 ⁄ 93; 99%). Fifty-two per cent (48 ⁄ 93) of IBS cases had constipation, almost all (47 ⁄ 48) also reporting presence of diarrhoea symptoms. Twenty-one per cent (51 ⁄ 248) of participants reported dyspepsia symptoms. Fifteen per cent (36 ⁄ 248) reported both IBS symptoms and dyspepsia symptoms, while 57% (140 ⁄ 248) reported neither IBS nor dyspepsia symptoms. Sensitivity analysis of the BDQ-derived case definition of IBS was also conducted. For all study participants, we reviewed medical records to identify presence of an IBS diagnosis or of two or more symptoms compatible with IBS anywhere in the medical record within a 1-year time period before and also after questionnaire administration. Furthermore, the chart review of the 93 BDQ-derived IBS patients identified possible alternate organic explanations of their symptoms in only three patients (n = 1 endometriosis, n = 1 celiac sprue and n = 1 pelvic mass). Among all participants, the mean BDI score for depressive symptoms was 16.2 (s.d.: 14.3), indicating mild depression symptoms. Half (53%) of women scored in the minimal depression range (0–13), while 14% scored in the mild (14–19), 13% moderate
(20–28) and 21% in the severe range for depression (29–63). The mean BAI score for anxiety symptoms was 17.1 (s.d.: 13.7), indicating moderate anxiety symptoms overall. Nearly one third of women (29%) were categorized as minimal anxiety (0–7), while 23% scored in the mild (8–15), 24% moderate (16–25) and 23% in the severe (26–63) range for anxiety. The mean score for PTSD symptoms, as measured by the MPTSD, was 76.7 (s.d.: 25.0). Approximately 15% of all women screened positive for PTSD (M-PTSD score ‡107).
Sociodemographic characteristics associated with IBS and dyspepsia Table 2 presents sociodemographic differences between participants with IBS and dyspepsia and those with neither IBS nor dyspepsia symptoms. A larger proportion of younger women veterans reported IBS (46%) and dyspepsia (43%) symptoms than those without IBS or dyspepsia symptoms (37%); however, the differences were not statistically significant. There were also no significant differences in race ⁄ ethnicity, education or marital status between those with IBS or dyspepsia and those with neither symptom.
Table 2. Selected sociodemographic characteristics of women veterans identified at a VA Women’s Clinic (n = 248): grouped by presence or absence of irritable bowel syndrome and dyspepsia symptoms IBS and dyspepsia absent (n = 140) No. (%) Age (years)
