Context: The role of triglycerides in the risk of ischemic stroke remains controversial. Recently, a strong association was found between elevated levels of nonfasting triglycerides, which indicate the presence of remnant lipoproteins, and increased risk of ischemic heart disease.
Objective: To test the hypothesis that increased levels of nonfasting triglycerides are associated with ischemic stroke in the general population.
Design, setting, and participants: The Copenhagen City Heart Study, a prospective, Danish population-based cohort study initiated in 1976, with follow-up through July 2007. Participants were 13,956 men and women aged 20 through 93 years. A cross-sectional study included 9637 individuals attending the 1991-1994 examination of the prospective study.
Main outcome measures: Prospective study: baseline levels of nonfasting triglycerides, other risk factors at baseline and at follow-up examinations, and incidence of ischemic stroke. Cross-sectional study: levels of nonfasting triglycerides, levels of remnant cholesterol, and prevalence of ischemic stroke.
Results: Of the 13,956 participants in the prospective study, 1529 developed ischemic stroke. Cumulative incidence of ischemic stroke increased with increasing levels of nonfasting triglycerides (log-rank trend, P < .001). Men with elevated nonfasting triglyceride levels of 89 through 176 mg/dL had multivariate-adjusted hazard ratios (HRs) for ischemic stroke of 1.3 (95% CI, 0.8-1.9; 351 events); for 177 through 265 mg/dL, 1.6 (95% CI, 1.0-2.5; 189 events); for 266 through 353 mg/dL, 1.5 (95% CI, 0.9-2.7; 73 events); for 354 through 442 mg/dL, 2.2 (95% CI, 1.1-4.2; 40 events); and for 443 mg/dL or greater, 2.5 (95% CI, 1.3-4.8; 41 events) vs men with nonfasting levels less than 89 mg/dL (HR, 1.0; 85 events) (P < .001 for trend). Corresponding values for women were 1.3 (95% CI, 0.9-1.7; 407 events), 2.0 (95% CI, 1.3-2.9; 135 events), 1.4 (95% CI, 0.7-2.9; 26 events), 2.5 (95% CI, 1.0-6.4; 13 events), and 3.8 (95% CI, 1.3-11; 10 events) vs women with nonfasting triglyceride levels less than 89 mg/dL (HR, 1.0; 159 events) (P < .001 for trend). Absolute 10-year risk of ischemic stroke ranged from 2.6% in men younger than 55 years with nonfasting triglyceride levels of less than 89 mg/dL to 16.7% in men aged 55 years or older with levels of 443 mg/dL or greater. Corresponding values in women were 1.9% and 12.2%. In the cross-sectional study, men with a previous ischemic stroke vs controls had nonfasting triglyceride levels of 191 (IQR, 131-259) mg/dL vs 148 (IQR, 104-214) mg/dL (P < .01); corresponding values for women were 167 (IQR, 121-229) mg/dL vs 127 (IQR, 91-181) mg/dL (P < .05). For remnant cholesterol, corresponding values were 38 (IQR, 26-51) mg/dL vs 29 (IQR, 20-42) mg/dL in men (P < .01) and 33 (IQR, 24-45) mg/dL vs 25 (IQR, 18-35) mg/dL in women (P < .05).
Conclusion: In this study population, nonfasting triglyceride levels were associated with risk of ischemic stroke.