The Correlation Study Between Subclinical Hypothyroidism And The Severity Of Coronary Heart Disease In The Elderly

Objective:(1)To compare the prevalence of CHD between elderly patients with SCH and elderly people with normal thyroid function.(2)To compare the distribution ratio of elderly SCH patients in different sexes and different age stages.(3)To explore whether SCH in the elderly is an independent risk factor for CHD.(4)To explore the correlation between serum thyroid hormone levels and the severity of coronary lesions in elderly patients with SCH.Methods:The study subjects were selected to be elderly people over 60 years old who visited Shanxi Bethune Hospital for the first time for CAG examination due to chest tightness and other discomforts from January 1,2021 to July 31,2022,and met the inclusion criteria for thyroid function tests.A total of 830 patients were included in this study,including 406 men and 424 women.The clinical data(including hospitalization number,gender,age,height,weight,smoking history,hypertension history,diabetes history,etc.),biochemical indicators(including TSH,FT3,FT4,TG,TC,HDL-C,LDL-C,HCY,etc.)and examination parameters(including LVEF,E/A)were collected.All study subjects underwent CAG after admission,and physicians performed a Gensini score based on the CAG results to assess the severity of coronary lesions.According to the results of CAG examination,the study subjects were divided into control group and CHD group,and the CHD group was divided into single lesion group,double branch lesion group and multi-branch lesion group according to the number of lesion vascular branches.According to the Gensini score,all the subjects was divided into mild lesion group(Gensini <30),moderate lesion group(30 ≤Gensini ≤60)and severe lesion group(Gensini >60).According to the results of thyroid function tests,all the subjects were divided into normal thyroid function group and elderly SCH group,and the elderly SCH group was further divided into mild SCH group(TSH<10mIU/L)and severe SCH group(TSH≥10mIU/L)according to serum TSH level.Results:1.The comparison between the elderly CHD group and the control group in terms of gender,smoking,hypertension and diabetes was statistically significant(P<0.05);the serum TG,TC,LDL-C,HC levels in the elderly CHD group were higher than those in the control group,and the serum HDL-C levels,LVEF and E/A values were lower than those in the control group,and the differences were statistically significant(P<0.05).In other respects,there was no statistically significant difference between the two groups(P>0.05).2.There were significant differences in the prevalence of CHD between different thyroid functional status groups(P<0.05),the prevalence of CHD was statistically significant between mild SCH and control(P<0.017),There were significant differences between the severe SCH group and the mild SCH group,and between the severe SCH group and the control group(P<0.017).3.Multivariate logistic regression analysis of risk factors for coronary heart disease showed that SCH in the elderly was still an independent risk factor for coronary heart disease after adjusting for potential confounding factors.4.The distribution of thyroid function status in the elderly population in different genders and different age strata was balanced and comparable,and the difference was not statistically significant(P>0.05).5.The difference in serum TSH level between lesion vascular branches was statistically significant(P<0.05);the difference in serum FT3 level was also statistically significant(P<0.05);however,there was no significant difference in serum FT4 level(P>0.05).6.The difference in serum TSH level was statistically significant(P<0.05)between Gensini score groups(P<0.05);the difference was also statistically significant(P<0.05)between the Gensini score groups;but there was no significant difference in serum FT4 level(P>0.05).7.Pearson linear correlation analysis showed that serum TSH levels were positively correlated with Gensini scores.8.Multivariate linear regression analysis showed that elevated serum TSH level was an independent risk factor for severe coronary artery disease after adjusting for potential confounding factors.Conclusion:(1)The risk of coronary heart disease in elderly patients with SCH was significantly higher than that of elderly people with normal thyroid function.(2)Patients with varying degrees of SCH were evenly distributed across all age groups over 60 years of age and had no gender differences.(3)SCH in the elderly is an independent risk factor for coronary heart disease.(4)The serum TSH level can be used as an independent predictor of coronary disease in older patients with SCH.