Objective

Higher serum leptin levels have been associated with a modestly higher incidence of cardiovascular disease in studies involving mostly Caucasian men. We aimed to assess the hypothesis that higher baseline levels of serum leptin are associated with higher risk of future cardiovascular disease in a diverse cohort.

Methods

The Multi-Ethnic Study of Atherosclerosis (MESA) is a modern, community-based, ethnically-diverse, and sex-balanced prospective cohort study of US adults free from cardiovascular disease. Serum leptin was measured in an ancillary study in 2002-2005. This analysis included 1905 MESA participants with baseline leptin and incident cardiovascular event data. Leptin levels were modeled as a log-transformed continuous variable and multivariable-adjusted Cox regression was performed for the primary outcome of hard cardiovascular disease, including coronary heart disease and stroke.

Results

The median follow-up was 7.6 years (25th-75th 7.1-8.3) with 7051 and 6738 person-years of follow-up in women and men. A hard cardiovascular disease event occurred in 47 women and 63 men. The age- and ethnicity-adjusted hazard ratio estimates for a 1 standard deviation increase in ln(leptin) were 1.16 in women (95% CI 0.78-1.73, p = 0.46) and 0.91 (95% CI 0.69-1.20, p = 0.51) in men. Pooling sexes, and adjusting for sex in addition to age and ethnicity, estimates were 0.98 (95% CI 0.78-1.23, p = 0.89). With additional adjustment for cardiovascular risk factors, the results remained nonsignificant: 0.87 (95% CI 0.68-1.11, p = 0.26).

Conclusion

In conclusion, in a modern, US prospective cohort study of multi-ethnic women and men of multi-ethnic backgrounds, leptin levels are not associated with incident cardiovascular events.