1 Journal Club Alcohol, Other Drugs, and Health: Current Evidence July–August 2012

2 Featured Article Prevalence of Alcohol Use Disorders Before and After Bariatric Surgery King WC, et al. JAMA. 2012;307(23):2516–2525.

3 Study Objective To assess the prevalence of pre- and post- operative alcohol use disorders (AUDs) in patients who underwent bariatric surgery and identify predictors of post-operative AUD in these patients.

4 Study Design Prospective cohort study of adults who underwent bariatric surgery at 10 US hospitals. Of 2458 participants, 1945 (79% female; 87% white; median age, 47 years; median body mass index [BMI], 46) completed preoperative (pre-op) assessments and postoperative (post-op) assessments at 1 and/or 2 years. The main outcome measure was past-year AUD symptoms (Alcohol Use Disorders Identification Test [AUDIT] score ≥8).

5 Assessing Validity of an Article About Harm Are the results valid? What are the results? How can I apply the results to patient care?

6 Are the Results Valid? Did the investigators demonstrate similarity in all known determinants of outcomes? Did they adjust for differences in the analysis? Were exposed patients equally likely to be identified in the two groups? Were the outcomes measured in the same way in the groups being compared? Was follow-up sufficiently complete?

7 Did the investigators demonstrate similarity in all known determinants of outcomes? Not applicable. –Case series design did not include an unexposed cohort. –Patients included in the analysis (compared with those excluded for failure to complete the AUDIT pre- or post-op) were older (median of 47 years versus 42 years), a greater percentage were white (87.0% versus 82.0%), and a smaller percentage were smokers (2.2% versus 4.1%). There were no significant differences between groups with respect to other characteristics.

8 Did they adjust for differences in the analysis? Results were adjusted for sex, age, smoking status, regular alcohol consumption, AUD pre-op, Interpersonal Support Evaluation List (ISEL-12) score, recreational drug use, surgical procedure used, and time (1st or 2nd year post-op).

99 Were exposed patients equally likely to be identified in the groups? Not applicable. - An unexposed group (no bariatric surgery) was not evaluated.

10 Were the outcomes measured in the same way in the groups being compared? Not applicable. - An unexposed group (no bariatric surgery) was not evaluated.

11 What are the Results? How strong is the association between exposure and outcomes? How precise is the estimate of the risk?

How strong is the association between exposure and outcome? How precise is the estimate of the risk? More than half of those reporting AUD at the preoperative assessment continued to have or had recurrent AUD (66/106; 62.3% [95% CI, 53.0%– 71.5%]). Among participants not reporting AUD at the preoperative assessment, 7.9% (95% CI, 6.4% – 9.4%; 101/1283) had postoperative AUD. More than half (101/167; 60.5% [95% CI, 53.1% – 67.9%]) of postoperative AUD was reported by those not reporting AUD at the preoperative assessment. 12

13 How Can I Apply the Results to Patient Care? Were the study patients similar to the patients in my practice? Was the duration of follow-up adequate? What was the magnitude of the risk? Should I attempt to stop the exposure?

14 Were the study patients similar to the patients in my practice? The median BMI among participants was 46; the mean age was 47, 68% were employed, nearly 80% were women, and nearly 90% were white.

15 Was the duration of follow-up adequate? Data were available on the majority of subjects at 1 and 2 years post operatively, an adequate duration.

16 What was the magnitude of the risk? Among participants not reporting AUD at the preoperative assessment, 7.9% (95% CI, 6.4%–9.4%; 101/1283) had postoperative AUD. More than half (101/167; 60.5% [95% CI, 53.1%–67.9%]) of postoperative AUD was reported by those not reporting AUD at the preoperative assessment.

17 Should I attempt to stop the exposure? Bariatric surgery, although not without risk, has been associated with health benefits including control of blood pressure and diabetes. Based on this research, patients planning to undergo bariatric surgery should be advised of the risk of developing an AUD.