Low-Density Lipoprotein Cholesterol Concentrations and Death Due to Intraparenchymal Hemorrhage

Abstract

Background-Few studies have examined the association between low levels of low-density lipoprotein (LDL) cholesterol and risk of intraparenchymal hemorrhage. Methods and Results-A total of 30 802 men and 60 417 women, 40 to 79 years of age with no history of stroke or coronary heart disease, completed a baseline risk factor survey in 1993 under the auspices of the Ibaraki Prefectural Health Study. Systematic mortality surveillance was performed through 2003, and 264 intraparenchymal hemorrhage deaths were identified. LDL cholesterol levels were calculated with the Friedewald formula. Persons with LDL cholesterol Ն140 mg/dL had half the sex-and age-adjusted risk of death due to intraparenchymal hemorrhage of those with LDL cholesterol Ͻ80 mg/dL. After adjustment for cardiovascular risk factors, the multivariable hazard ratio compared with persons with LDL cholesterol Ͻ80 mg/dL was 0.65 (95% CI 0.44 to 0.96) for those with LDL cholesterol 80 to 99 mg/dL, 0.48 (0.32 to 0.71) for 100 to 119 mg/dL, 0.50 (0.33 to 0.75) for 120 to 139 mg/dL, and 0.45 (0.30 to 0.69) for Ն140 mg/dL. These inverse associations were not altered substantially after the exclusion of persons with hypertriglyceridemia, after analysis with a Cox proportional hazard model with time-dependent covariates, or in sensitivity analysis for the potential effect of competing risks. Conclusions-Low LDL cholesterol levels are associated with elevated risk of death due to intraparenchymal hemorrhage.

Low Blood Chlesterol and Intraparenchymal Hemorrhage in Cohort Studies

“…Second, low blood cholesterol may reflect the nutritional status, which relates to death after onset, not to onset per se. An inverse association between low cholesterol and hemorrhagic stroke seems to be well observed when the endpoint of the cohort study is mortality, especially in non-Japanese populations 2,4) and a recent report from Japan 5,7,8) . Third, there may be some residual confounding factors that have not been considered, such as the socio-economic status.…”

“…Recently, Noda et al 8) demonstrated that low serum levels of LDLC were associated with an elevated risk of death due to intraparenchymal hemorrhage in the Ibaraki Prefectural Health Study, a populationbased cohort study of 91 219 Japanese. These inverse associations were not altered substantially after analysis with time-dependent covariates, or in sensitivity analysis for the potential effect of competing risks; however, as clearly shown in the tables of their article, most blood samples in this study were collected in the non-fasting state.…”

Treatment of Risk Factors to Prevent Stroke

“…Most epidemiological studies suggested the association between lower levels of total and LDL cholesterol and higher risk of hemorrhagic stroke [51,52]. In the SPARCL trial, statin increased the incidence of hemorrhagic stroke, but overall stroke risk was reduced.…”

Long-term exposure to elevated blood pressure and mortality from cardiovascular disease in a Japanese population: the Ibaraki Prefectural Health Study

“…11,12 A total of 38 of the 85 municipalities in the prefecture were included in this study. The participation rate for health checkups was 36.4% in these areas and was similar to the rate for the Ibaraki prefecture overall in 1993 (35.8%).…”