Elevated homocysteine level ups mortality risk in hypertensive adults

The interaction of hypertension and total plasma homocysteine (tHcy) levels contributes to the risk of all-cause mortality among middle-aged and older adults, a US study has found. In addition, hypertension may boost the ability of elevated tHcy to aggravate this risk.

This observational cohort study examined data from the National Health and Nutrition Examination Survey database (1999‒2002 survey cycle) to assess the interaction of hypertension and tHcy levels on the risk of all-cause and cardiovascular disease (CVD) mortality in adults.

The investigators applied a generalized additive model based on Cox proportional hazards models to estimate the association of tHcy levels with all-cause and CVD mortality. They also performed stratification analyses by sex and renal function.

A total of 5,724 individuals aged 40‒85 years (mean age 60.7 years, 49.6 percent men) were included in the analysis, of whom 704 (12.3 percent) died, with 339 CVD deaths after a median follow-up of 5.58 years.

In the fully adjusted model, an increase of 1 μmol/l in plasma tHcy level resulted in an 8-percent higher risk of all-cause mortality and 7-percent elevated risk of CVD mortality in participants with hypertension. The adjusted hazard ratios were 1.08 (95 percent confidence interval [CI], 1.06‒1.10) for all-cause mortality and 1.07 (95 percent CI, 1.04‒1.10) for CVD mortality.

Distinct interactive effects were noted between hypertension and tHcy levels on the risk of all-cause mortality (p_interaction=0.031).