Relationship Between Serum Total Cholesterol And Mortality From Coronary Heart Disease,All Cause Death In The Senile Male Population With Coronary Artery Disease

Objiect:To evaluate the association between Serum total cholesterol(TC)and mortality from all-cause and coronary heart disease(CHD)in the male elderly with CHD,providing some evidences for establishing the lowest limitation of intensive lipid-lowering in elderly.Methods:In this retrospective cohort study,878 subjects aged over 65 years(mean 74.1±4.61 year)with CHD were recruited from 1996 to 2007 in Chinese PLA General Hospital.According to their TC level,the patients were divided into 4 groups:group1(TC＜4.16mmol/L),group2(4.16≤TC＜4.68mmol/L),group3 (4.68mmol/L≤TC＜5.2mmol/L),group4(TC≥5.2mmol/L).The associations between baseline Serum TC level and mortality from all-cause and CHD were performed by using Cox multivariate proportional hazards regression.Results:(1)Compared with group2,before adjustment,the risk of CHD death in groupl and 4 increased respectively 131%(RR=2.31,95%CI=1.07-5.00, P=0.034),28%(RR=1.28,95%CI=1.01-1.61,P=0.039).The difference between group 2 and 3 was not statistical significance,the relationship between TC level and CHD death is U type.After adjustment for age,TC,smoking,history of hypertension and dyslipidemia,lipid-lowering therapy,the CHD death RR increased 271%(RR=3.71,95%CI=1.15-11.96,P=0.028),the relationship between TC level and CHD death is L type.(2)Compared with group2 and 3, the cumulative survival rate for CHD death of groupl are lower(P＜0.05),that is similar to the group 4.(3)The death causes are cardio-cerebrovascular disease (38.21%),respiratory system disease(26.83%),malignant tumor(26.42%) and others(8.54%)by turns in the male elderly with CHD.And the main death cause in cardio-cerebrovascular disease is CHD(31.30%).(4)Compared with the groupl,The all cause death relative risk(RR)of group2,3 and 4 decreased respectively 33%(RR=0.67,95%CI=0.46-0.99,P=-0.044),19%(RR=0.81, 95%CI=0.67-0.98,P=0.032),33%(RR=0.87,95%CI=0.78-0.98,P=0.018).(5) In the aged 75 and older group,Compared with the groupl,the all cause death RR of the group4 decreased 13%(RR=0.87,95%CI=0.76-1.00,P=0.043).(6)Cox multivariate proportional hazards regression analysis suggested,in single factor analysis and after adjusted for conventional risk factors for CHD,that age,smoking,drinking,fasting plasma glucose and hypertension were the risk factors for all-cause death.Age,TC,smoking,hypertension,dyslipidemia were the risk factors for increasing CHD death.Lipid-lowering therapy is a protective factor.Conclusion:(1)In senile male CHD population,"U or L"type relationship lies between TC concentrations and CHD death.TC level that is too low could increase the mortality of CHD.The above results showed that lipid-lowering is beneficial in senile male CHD population,but the TC level＜4.16mmol/L is harmful.(2)the TC level＜4.16mmol/L may be a signal for increasing death risk. Lipid-lowering therapy is beneficial for the elderly.While intensive lipid-lowering therapy maybe not need for the older(≥75)patients with hypercholesterolemia.