血清同型半胱氨酸及血脂水平、糖尿病、年龄与冠状动脉病变程度关系的回归树分析

Regression tree analysis of the relationship between homocysteine, diabetes, lipids, age and severity of coronary artery disease

目的 :研究血清同型半胱氨酸水平与冠状动脉 (冠脉 )病变程度的关系及高同型半胱氨酸血症与其它危险因素的关系。方法 :用断面调查的方法 ,收集了进行诊断性冠脉造影术的 1 53例患者 ,采用高压液相方法检测其血清同型半胱氨酸水平 ,并收集冠心病其它危险因素的资料。结果 :单因素分析结果显示 :冠脉病变组吸烟年限、患糖尿病的比例、血清ApoA1水平及血清同型半胱氨酸水平等明显高于无冠脉病变组。多元Logistic回归分析证实HCY和糖尿病的优势比 (OR)均大于 1 ,并有显著差异。用前进法观察偏回归系数证实这两个因素是冠脉病变的独立危险因素。进一步采用回归树对结果进行分析发现 :同型半胱氨酸与其它危险因素相比更重要 ,它与其它危险因素之间存在交互作用 ,尤其在糖尿病、高脂血症及高龄患者可加重冠脉病变的程度。结论 :高同型半胱氨酸是冠心病的危险因素 。

Objective: To study the association of the homocysteine (HCY)level with the severity of coronary atherosclerosis and examine the interaction between elevated homocysteine level and conventional risk factors.Methods: In a cross sectional study, fasting serum homocysteine levels of 153 cases undergoing diagnostic coronary angiography were measured .So were serum cholesterol and lipoprotein The information on conventional risk factors was collected by interviews.Results: By univariate analysis, patients had higher serum HCY level (19.68±11.96 μmol·L 1 ) than controls(11.28±4.17 μmol·L 1 , P <0.01). Patients also had longer smoking years(15.1±16.3) and higher rates of diabetes(38.2%) and lower ApoA1 level(1226.4±225.9 mmol·L 1 ) than controls(8.4±12.8, 6%, 1303.9 ±179.9; P <0 05, P <0.01, P <0.05). By logistic regression analysis, OR of elevated HCY level and diabetes were all ≥1, which means they were two independent factors in coronary atherosclerosis. Data were further analyzed by regression trees , the results(HCY, diabetes and ApoA1) were in consistence with that of univariate analysis,and HCY was used for two times. Of particular interest was that we found TC levels were also used for two times in this tree. The results showed that subjects with elevated TC levels, lower ages (<60 years) and higher Lp(a) levels had higher scores than those subjects with lower TC levels, lower Lp(a) levels, higher ages(>60 years), that is, these factors were positively related with the scores. The joint effects of conventional risk factors and the interactive effects between homocysteine and these risk factors were noted. It showed the relative risks in various combinations of HCY levels and the conventional risk factors. An increased fasting homocysteine level showed a more than multiplicative effect on risk in patients with diabetes or elevated serum lipids or older ages. HCY was one of the most important factor in the genesis of coronary atherosclerosis.Conclusion: Elevated homocysteine confers a graded risk, and may enhance the effects of diabetes in the genesis of coronary atherosclerosis.