| Background:Increased plasma total homocysteine(t Hcy)is a risk factor for cognitive impairment in the general population.However,there are limited data on the relationship between plasma t Hcy concentration and cognitive function in hypertensive people.This study aimed to understand the relationship between plasma t Hcy levels and cognitive function in Chinese patients with H-type hypertension.Methods:The study population was participants in the ongoing Chinese Registry of H-type Hypertension,including 9527 Chinese adults in the final analysis.Using a linear regression model,piece-wise binary linear regression models and smoothed curve fitting(penalty spline method)determined the relationship between plasma t Hcy levels and cognitive function.Results:A total of 9527 participants out of 10,289 eligible participants(4572 men and4955 women,aged 27-96 years)were included in the statistical analysis.Overall,the average age was 63.7 ± 9.8 years.The fully adjusted smooth curve confirmed that the association between plasma t Hcy and Mini-Mental State Examination(MMSE)was nonlinear.Moreover,threshold effect analysis showed that the inflection point of plasma t Hcy was 27.1μmol/L.Analyses using piece-wise binary linear regression models confirmed that the β(95% CI)of MMSE was-0.91(-1.23,-0.60)on the left side of an inflection point(P<0.001),and no association between Hcy and MMSE was found on the right of an inflection point(P for trend< 0.001).Subgroup analysis showed that gender influenced the negative association between plasma t Hcy levels and MMSE scores in those with Hcy less than 27.1μmol/L(p for interaction <0.005).Conclusions:Our study suggested plasma t Hcy concentration was independently associated with worse cognitive function(Hcy:10-27.1μmol/L),and we found saturation effect of plasma t Hcy on MMSE among Chinese H-Type hypertension populations(Hcy≥27.1μmol/L).Moreover,this showed that the threshold differed according to sex,with female patients having a lower threshold than male patients. |
