Isolated low levels of high-density lipoprotein cholesterol and stroke incidence: JMS Cohort Study.

Background: The cardiovascular relevance of isolated low levels of high-density lipoprotein cholesterol (HDL-C) is yet to be determined. Stroke often leads to long-term disability, and thus, not only stroke mortality but also stroke incidence is a topic of research. Although isolated low HDL-C level has been found to be a predictor for stroke mortality previously, whether it can predict stroke incidence is unknown.

Methods: In the Jichi Medical School cohort study, 11 025 community-living residents without a history of stroke were examined. Hazard ratios (HRs) for isolated and non-isolated low HDL-C levels were calculated relative to those for normal HDL-C levels in stroke patients using Cox's regression models.

Results: During the mean follow-up period of 10.7 years, 412 residents had their first-ever stroke. The multivariable-adjusted HRs for the levels of isolated and non-isolated low HDL-C were 1.11 (95% confidence interval, 0.85-1.44) and 1.35 (1.01-1.81), respectively, when compared to that for normal HDL-C.

Conclusion: Low HDL-C levels with other dyslipidemias may contribute to the incidence of stroke, not isolated low HDL-C.