1 Journal Club Alcohol, Other Drugs, and Health: Current Evidence November–December 2010

2 Featured Article Patterns of Alcohol Consumption and Ischaemic Heart Disease in Culturally Divergent Countries The Prospective Epidemiological Study of Myocardial Infarction (PRIME) Ruidavets JB, et al. BMJ. 2010:23;341:c6077.

3 Study Objective To investigate the effect of alcohol intake patterns on ischemic heart disease in 2 countries with contrasting lifestyles (Northern Ireland and France).

4 Study Design Analysis of cohort data from the Prospective Epidemiological Study of Myocardial Infarction (PRIME) from 1 center in Belfast and 3 centers in France. The sample included 9778 men aged 50–59 and free of ischemic heart disease at baseline. Participants were assessed at baseline for: –weekly alcohol consumption– frequency of consumption –incidence of binge drinking*– type of beverage consumed –incidence of regular drinking† *Consumption of >50 g alcohol at least 1 day per week. †Consumption at least 1 day a week, alcohol <50 g if on only 1 occasion.

5 Study Design (cont’d) The relationship between baseline characteristics, coronary events (myocardial infarction [MI] and coronary death), and angina events over 10-year follow-up was assessed using Cox’s proportional hazards regression analysis.

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

7 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?

8 Did the investigators demonstrate similarity in all known determinants of outcomes? Did they adjust for differences in the analysis? The sample included men only, similar in age and with no baseline history of ischemic heart disease. Analyses were adjusted for the following factors known to be predictive of ischemic heart disease: − age − education − waist circumference − systolic blood pressure − diabetes, dyslipidemia, or hypertension − physical activity − tobacco consumption, pack years − apolipoprotein A-1 concentration − apolipoprotein B concentration

9 Were exposed patients equally likely to be identified in the groups?  Although this study addressed drinking pattern, self-reported alcohol consumption on a typical week in the year prior to baseline examination was the exposure.  Follow-up did not assess for changes in consumption over time.

10 Were the outcomes measured in the same way in the groups being compared?  Extensive clinical information was gathered for any patient who reported a possible clinical event over the 10-year follow-up period: −hospital and physician notes; hospital admissions; electrocardiograms; MI biomarkers; surgical procedures; angioplasty; myocardial perfusion scintigraphy; echocardiography; postmortem information on participants who died.  A committee comprised of 1 PRIME researcher, 1 member of the PRIME coordinating center, and 3 independent cardiologists reviewed all collected medical data.

11 Was follow-up sufficiently complete? Of the overall sample (N=9778), –317 men (3%) were lost to follow-up. –215 (2%) refused continued participation. –653 (6.1%) died.

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

13 How strong is the association between exposure and outcome? How precise is the estimate of the risk? –The hazard ratio (HR) for coronary events in binge drinkers * compared with regular drinkers † was 1.81 (95% CI, 1.05– 3.11) in Belfast and 1.93 (95% CI, 0.46–7.40) in France. –Combining all sites, the HR for coronary events compared with regular drinkers was 2.03 (95% CI, 1.41–2.94) in never drinkers and 1.97 (95% CI, 1.21–3.22) in binge drinkers. The HR for former drinkers compared with regular drinkers was 1.57 (95% CI, 1.11–2.21). –Alcohol intake was not associated with incidence of anginal events. *Consuming ≥50 g alcohol at least 1 day per week. †Consuming <50 g alcohol at least 1 day per week.

14 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?

15 Were the study patients similar to the patients in my practice? Subjects were Irish and French men aged 50–59 at baseline. Further race/ethnicity data were not provided.

16 Was the duration of follow-up adequate? Yes. Follow-up was at 10 years.

17 What was the magnitude of the risk? Compared with regular drinkers, the HR for coronary events was 2.03 in never drinkers and 1.97 in binge drinkers. The HR for former drinkers compared with regular drinkers was 1.57.

18 Should I attempt to stop the exposure? The results suggest a cardiovascular benefit with consumption of <50 g alcohol at least 1 day per week.