ObjectiveTo determine the blood level of homocysteine （Hcy） and its influencing factors among Shanghai rural residents with high risk of stroke and to verify if hyperhomocysteinemia （HHcy） is a main biomarker of stroke.

MethodsWith a clustered random sampling method， questionnaire survey and physical examination were conducted among 4 073 rural residents， aged 55 years and above， in Luojing community， Shanghai， in 2018. A total of 470 residents were at high-risk for stroke based on screening of plasma Hcy and other blood indicators. Multivariate logistic regression method was performed for data analysis.

ResultsThe overall level of Hcy was （18.92±6.37）μmol/L， with （20.40±5.89）μmol/L for men and （17.87±2.12）μmol/L for women （t=5.431，P<0.001）. HHcy was detected in 78.94%（371/470） of the participants， in which 85.77%（235/274） were men and 69.39%（136/196） were women （χ²=12.400，P=0.001）. In the high-risk male group， subjects with smoking history， overweight or obesity， exercise frequency <1 h/d， and hypertension has a higher detection rate of HHcy than those without smoking history， normal body mass index， exercise frequency ≥1 h/d and without hypertension （χ²=11.340，8.170，8.200， and 12.400， respectively， all P<0.01）. However， there was no significant difference in HHcy detection rate in different age groups and between the patients with or without diabetes， and dyslipidemia（χ²=3.120，2.311， and 0.984， respectively， all P>0.05）. In the high-risk women group， HHcy detection rate increased with age （χ²=13.874，P<0.01）， and it was higher in participants with overweight or obesity， exercise frequency < 1 h/d， hypertension， and dyslipidemia（χ²=10.278， 13.840， 14.100， and 12.330， respectively， all P<0.01）. Unconditional logistic regression analysis showed that the factors affecting HHcy in the high-risk population of stroke include being male， smoking， hypertension， overweight and obesity.

ConclusionScreening of high-risk populations for stroke should include blood level of Hcy.