Leptin and coronary heart disease: prospective study and systematic review

J Am Coll Cardiol. 2009 Jan 13;53(2):167-75. doi: 10.1016/j.jacc.2008.09.035.

Abstract

Objectives: This study sought to better determine the link between leptin and coronary heart disease (CHD).

Background: Circulating leptin is considered a risk factor for CHD but larger studies are needed.

Methods: Leptin levels were measured in 550 men with fatal CHD or nonfatal myocardial infarction and in 1,184 controls nested within a prospective study of 5,661 British men and set in context with a meta-analysis.

Results: Baseline leptin correlated with body mass index (BMI), blood pressure, total cholesterol, triglyceride, and inflammatory markers; correlations persisted after BMI adjustment. The within-person consistency of leptin values over 4 years (correlation coefficient: 0.79; 95% confidence interval [CI]: 0.73 to 0.83) was higher than those of some established cardiovascular risk factors. In a comparison of individuals in the top third with those in the bottom third of baseline leptin, the age- and town-adjusted odds ratio for CHD was 1.25 (95% CI: 0.96 to 1.62), decreasing to 0.98 (95% CI: 0.72 to 1.34) after adjustment for BMI. A systematic review identified 7 prospective reports with heterogeneous findings (I(2) = 60%, 13% to 82%). The combined adjusted risk ratio across all studies was 1.44 (95% CI: 0.95 to 2.16) in a comparison of extreme thirds of leptin levels. The inconsistency between studies was partially explained by sample size, with combined estimates from studies involving >100 CHD cases (1.28, 95% CI: 0.80 to 2.04) being somewhat weaker than those from smaller studies (1.81, 95% CI: 0.76 to 4.31).

Conclusions: Previous studies appear to have overestimated associations of leptin and CHD risk. Our results suggest a moderate association that is largely dependent on BMI.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Review
  • Systematic Review

MeSH terms

  • Blood Pressure
  • Body Mass Index
  • Case-Control Studies
  • Cholesterol / blood
  • Coronary Disease / blood*
  • Female
  • Humans
  • Leptin / blood*
  • Male
  • Middle Aged
  • Prospective Studies
  • Random Allocation
  • Risk Factors
  • Triglycerides / blood

Substances

  • Leptin
  • Triglycerides
  • Cholesterol