Association Study of <i>MTHFR</i> C677T Polymorphism With Homocysteine Level and Coronary Heart Disease in Elderly Patients

<b>Objective:</b> To investigate the relationship between methylenetetrahydrofolate reductase (<i>MTHFR</i>) C677T gene polymorphism and coronary heart disease (CHD) in the elderly patients living in the coastal area of eastern Zhejiang Province in China. <b>Methods:</b> From September 2021 to May 2022, 163 elderly patients (male ≥ 55 years old, female ≥ 65 years old) admitted to the cardiology department in the Ningbo Lihuili Hospital were collected. Among these patients, 90 patients were diagnosed with CHD (CHD group) and 79 patients did not have CHD (control group). The homocysteine (Hcy) level was measured by the blood biochemical test, and the <i>MTHFR</i> genotype was detected by the PCR fluorescence probe method. <b>Results:</b> Compared with the control group, the CHD group showed a significantly higher distribution frequency of TT genotype (<i>X</i> ² = 5.137, <i>p</i> < 0.05) and a lower frequency of CC genotype (<i>X</i> ² = 6.560, <i>p</i> < 0.05), indicating that elderly people with <i>MTHFR</i>677 TT genotype are more likely to have CHD. In addition, the Hcy level of TT genotype in the CHD group and the control group were both obviously higher than that of CT genotype and CC genotype (<i>p</i> < 0.05). Finally, the univariate and multivariate logistic regression analyses showed that gender, hypertension, diabetes, and <i>MTHFR</i>677 TT genotype were independent risk factors for CHD (<i>p</i> < 0.05). <b>Conclusion:</b> <i>MTHFR</i> C677T mutation is significantly associated with the serum Hcy, and is an important genetic risk for CHD development in the elderly people living in the coastal area of eastern Zhejiang province, China.