[Screening for low-density lipoprotein receptor gene mutations in familial hypercholesterolemia Chinese].

OBJECTIVE: To screen the mutations of low-density lipoprotein receptor (LDLR) gene in Chinese familial hypercholesterolemia (FH) patients. METHODS: 7 patients with clinical phenotype of homozygous FH and their parents were investigated for mutations in all the eighteen exons of LDLR gene. Screening was carried out using PCR-SSCP and direct DNA sequencing and LDLR gene mutation database was searched to identify the alteration. In addition, the apolipoprotein B gene (apo B) was screened for known mutations (R3500Q) that caused familial defective apo B100 (FDB) with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). RESULTS: Nine mutations in the LDLR gene were identified in the FH patients. All the mutations except C255R have not been published in the LDLR gene mutation database. No mutation of apo B100 (R3500Q) was observed. CONCLUSIONS: Chinese FH patients may have specific spectrum and regional difference of LDLR gene mutations. Apolipoprotein B-100 gene mutation might not be the main cause of hypercholesterolemia patients in China.

Alcohol intake and risk of stroke: a dose-response meta-analysis of prospective studies.

BACKGROUND: Alcohol intake is inconsistently associated with the risk of stroke morbidity and mortality. The purpose of this study was to summarize the evidence regarding this relationship by using a dose-response meta-analytic approach. METHODS: We performed electronic searches of PubMed, EMBASE, and the Cochrane Library to identify relevant prospective studies. Only prospective studies that reported effect estimates with 95% confidence intervals (CIs) of stroke morbidity and mortality for more than 2 categories of alcohol intake were included. RESULTS: We included 27 prospective studies reporting data on 1,425,513 individuals. Low alcohol intake was associated with a reduced risk of total stroke (risk ratio [RR], 0.85; 95% CI: 0.75-0.95; P=0.005), ischemic stroke (RR, 0.81; 95% CI: 0.74-0.90; P<0.001), and stroke mortality (RR, 0.67; 95% CI: 0.53-0.85; P=0.001), but it had no significant effect on hemorrhagic stroke. Moderate alcohol intake had little or no effect on the risks of total stroke, hemorrhagic stroke, ischemic stroke, and stroke mortality. Heavy alcohol intake was associated with an increased risk of total stroke (RR, 1.20; 95% CI: 1.01-1.43; P=0.034), but it had no significant effect on hemorrhagic stroke, ischemic stroke, and stroke mortality. CONCLUSIONS: Low alcohol intake is associated with a reduced risk of stroke morbidity and mortality, whereas heavy alcohol intake is associated with an increased risk of total stroke. The association between alcohol intake and stroke morbidity and mortality is J-shaped.

Effect of calcium or vitamin D supplementation on vascular outcomes: a meta-analysis of randomized controlled trials.

BACKGROUND: Whether calcium or vitamin D supplementation reduces serious vascular outcomes in older people remains unclear. We conducted a meta-analysis based on randomized controlled trials to evaluate the effect of calcium or vitamin D supplementation on the risk of major cardiovascular outcomes. METHODS: We performed electronic searches in PubMed, Embase, and the Cochrane Library to identify relevant randomized controlled trials. Odds ratios (ORs) were used to measure the effect of calcium or vitamin D supplementation on the risk of major vascular outcomes with a random-effect model. RESULTS: Of the 1643 identified studies, we included 11 trials reporting data on 50,252 individuals. These studies reported 2685 major cardiovascular events, 1097 events of myocardial infarction, and 1350 events of stroke. Calcium or vitamin D supplementation did not have an effect on major cardiovascular events (OR, 1.03; 95% confidence interval [CI]: 0.94-1.12; P=0.54), myocardial infarction (OR, 1.08; 95% CI: 0.96-1.22; P=0.21), or stroke (OR, 1.01; 95% CI: 0.91-1.13; P=0.80) when compared to the effect with a placebo. Subgroup analysis indicated that calcium supplementation alone might play an important role in increasing the risk of major cardiovascular events, myocardial infarction, and stroke, but this difference could not be identified as statistically significant. Furthermore, males seem to experience more harmful effects with supplements of calcium or vitamin D than the effects experienced by females. CONCLUSIONS: Calcium supplementation might increase the risk of major cardiovascular events, myocardial infarction, and stroke compared to the risk with a placebo.