Association between serum cholesterol and noncardiovascular mortality in older age

Abstract

Objectives: To clarify the association between cholesterol and noncardiovascular mortality and to evaluate how this association varies across age groups.

Design: Prospective population-based cohort study.

Setting: Rotterdam, the Netherlands.

Participants: Adults aged 55 to 99 (N = 5,750).

Measurements: Participants were evaluated for total cholesterol and subfractions and followed for mortality for a median of 13.9 years. Total cholesterol and its subfractions were evaluated in relation to noncardiovascular mortality. Cox regression analyses were conducted in the total sample and within age-groups (55-64, 65-74, 75-84, ≥85).

Results: Age- and sex-adjusted analyses showed that each 1-mmol/L increase in total cholesterol was associated with an approximately 12% lower risk of noncardiovascular mortality (hazard ratio (HR) = 0.88, 95% confidence interval (CI) = 0.84-0.92, P < .001). Age group-specific analyses demonstrated that this association reached significance after the age of 65 and increased in magnitude across each subsequent decade. This was driven largely by non-high-density lipoprotein cholesterol (non-HDL-C) (HR = 0.89, 95% CI 0.85-0.93, P < .001) and was partly attributable to cancer mortality. Conversely, HDL-C was not significantly associated with noncardiovascular mortality (HR = 0.92, 95% CI 0.79-1.07, P = .26).

Conclusion: Higher total cholesterol was associated with a lower risk of noncardiovascular mortality in older adults. This association varied across the late-life span and was stronger in older age groups. Further research is required to examine the mechanisms underlying this association.