title: Obesity or smoking: Which factor contributes more to the incidence of myocardial infarction?
abstract: OBJECTIVE
  Comparing the contributions of smoking and obesity to the risk of myocardial infarction (MI) can help prioritize behavioral modifications. The objective of this study was to determine the relative risk of smoking, obesity and the joint burden on the risk of MI.
  
  
  METHODS
  This is a retrospective cohort study of data accessed from electronic medical records of the largest health care organization in Israel. The study population included all 738,380 members of Clalit Health Services, with at least one smoking status and one BMI assessment recorded in 2009 or 2010, aged 40-74years, who were MI-free before 2009. Obesity was defined as BMI >30kg/m(2). New and primary MI between January 1 and December 31, 2011 were recorded.
  
  
  RESULTS
  Rates of MI were: 0.18% for non-obese never smokers, 0.25% for obese never smokers, 0.40% for non-obese past smokers, 0.50% for obese past smokers, 0.53% for non-obese current smokers and 0.66% for obese current smokers. Among non-obese individuals, past smokers and current smokers had a greater risk of MI than did never smokers, after adjusting for age, gender and socioeconomic position (OR, 1.45; 95% CI, 1.23-1.70 and OR, 2.35; 95% CI, 2.10-2.63, respectively). The burden of obesity increased the risk of MI for never smokers but the burden of obesity did not elevate the risk of MI when combined with current or past smoking groups, after adjusting for comorbidities.
  
  
  CONCLUSIONS
  Past and, more so, current smoking confers greater risk for MI than obesity.
authors.affiliation: Internal Medicine D, Hasharon Hospital, Rabin Medical Center, Petah Tikva, Israel. Electronic address: daniel3@013.net.
authors.forename: Dror
authors.initials: D
authors.lastname: Dicker
authors.affiliation: Clalit Research Institute, Chief Physician's Office, Clalit Health Services, Tel Aviv, Israel.
authors.forename: Becca S
authors.initials: BS
authors.lastname: Feldman
authors.affiliation: Clalit Research Institute, Chief Physician's Office, Clalit Health Services, Tel Aviv, Israel; Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA.
authors.forename: Maya
authors.initials: M
authors.lastname: Leventer-Roberts
authors.affiliation: Clalit Research Institute, Chief Physician's Office, Clalit Health Services, Tel Aviv, Israel.
authors.forename: Arriel
authors.initials: A
authors.lastname: Benis
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000789:Angina, Unstable / Q000453:epidemiology; D016022:Case-Control Studies; D015331:Cohort Studies; D001026:Coronary Artery Bypass / Q000706:statistics & numerical data; D003920:Diabetes Mellitus / Q000453:epidemiology; D005260:Female; D006331:Heart Diseases / Q000453:epidemiology; D006801:Humans; D006949:Hyperlipidemias / Q000453:epidemiology; D006973:Hypertension / Q000453:epidemiology; D015994:Incidence; D007557:Israel / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology*; D009765:Obesity / Q000453:epidemiology*; D062645:Percutaneous Coronary Intervention / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking / Q000453:epidemiology*
keywords: Myocardial infarction; Obesity; Smoking