ABSTRACT
Objective To investigate the impact of high plasma LDL-C level with or without metabolic syndrome(MS) on the incidence of stroke in Chinese adults. Methods Totally 42 626 subjects (25 -75 years old) from Chinese National Health and Nutrition Survey in 2002 were stratified four groups based on plasma LDL-C level: < 2. 00 mmol/L group, 2. 00 -2. 50 mmol/L group, 2. 51 -3.31 mmol/L group, and ≥ 3.32 mmol/L group. The prevalence of MS (with 2005 International Diabetes Federation criteria) and stroke and the risk factors of stroke were compared among the four groups. Results ( 1 ) The prevalence of MS and stroke increased with rising of LDL-C level. The prevalence of MS in LDL-C≥3. 32 mmol/L group increased 2. 5 times (7, 9% vs 20. 1% ) as compared with that in LDL-C < 2. 00 mmol/L group and the prevalence of stroke increased 4. 2 times(0. 5% vs 2. 1% ), all P <0. 01. (2) In subjects with similar LDL-C level, the prevalence of stroke was significantly higher in a subgroup with MS than that without (P <0. 01 ). (3) After adjustment for age, sex and smoking, logistic regression analysis showed that both LDL-C level and MS were positively associated with the development of stroke; the odds ratio (OR) was 2. 35 and 3. 15 ( P < 0. 0001 ), respectively. (4) Compared with the subgroup of LDL-C < 2. 00 mmol/L without MS, OR for stroke in the subgroups of LDL-C 2. 00 -2. 50 mmol/L, 2. 51 -3. 31 mmol/L, and ≥ 3. 32 mmol / L without MS was 1.03, 1. 89, and 2.08, whereas the OR for stroke in the subgroups with MS and similar level of LDL-C was 4. 38, 5.23 and 6. 15 ; this indicated that the risk of stroke in subjects with MS increased by 3 - 4 times compared with subjects without ( P < 0. 0001 ). Conclusion Both high LDL-C level and MS are independent risk factors of stroke, but the risk of stroke will be further increased in the presence of high LDL-C level plus MS. It is suggested that combined intervention therapy of LDL-C and MS will play an important role in the prevention of stroke.
ABSTRACT
<p><b>OBJECTIVE</b>To explore the association between body mass index (BMI) and mortality in the middle-aged and elderly population of Beijing.</p><p><b>METHODS</b>A prospective cohort study was carried out in a natural population (aged 40 and over) in September 1991, totaling 6 209 subjects. After a baseline survey for risk factors, all the subjects were followed-up throughout December 1999. All deaths occurred during the follow-up period were registered and encoded according to ICD-9. Proportional hazard regression was used to examine the relationship between BMI (body weight in kilograms/height in square meters) and overall and cause-specific mortality.</p><p><b>RESULTS</b>During the past ten years, five leading causes of death in the middle-aged and elderly population of Beijing were cardiovascular disease (CVD), cor pulmonale, digestive malignant tumor, sudden death without definite cause and lung cancer, which accounting for 33.3%, 13.8%, 11.2%, 7.4% and 5.6% of the total deaths, respectively. The minimum overall mortality in all population and in non-smokers were seen in those with BMI of 23.6 - 26.2. Compared with those with BMI of 23.6 - 26.2, the relative risks (RR) for all-cause mortality in all population and non-smokers with BMI less than 21.2 and equal to or greater than 26.2 were 1.7, 1.3, 1.9 and 1.5, respectively after adjusted for age, gender, smoking and alcohol drinking. BMI correlated positively with death risk due to CVD in non-smokers, with an RR of 1.2 for those with BMI > 26.2 to non-smokers with BMI < 21.2 after adjusted for age, gender and alcohol drinking. A U-shaped correlationship between BMI and deaths due to other specific causes, including cor pulmonale, digestive malignant tumor, lung cancer, pneumonia and sudden death without definite causes. With the minimum cause-specific death rates all at BMI of 23.6 - 26.2. In comparison with those with BMI of 23.6 - 26.2, RRs for these five cause-specific mortality were 14.8, 1.1, 5.6, 2.4 and 2.6, respectively for non-smokers with BMI < 21.2 and 3.0, 1.9, 3.7, 2.2 and 1.5, respectively for non-smokers with BMI >/= 26.2 after adjusted for age, gender, and alcohol drinking. The proportion of deaths due to CVD was the highest in each BMI group, with a range of 28.0% - 54.8%.</p><p><b>CONCLUSIONS</b>There exists a U-shaped correlationship between BMI and overall mortality in the middle-aged and elderly population in Beijing. CVD remains the top leading cause of death in natural population, and its death risk increased with BMI.</p>