Hypertension, concurrent cardiovascular risk factors and mortality: the Singapore Cardiovascular Cohort Study

The current hypertension (HTN) guidelines recommend the assessment of other cardiovascular disease (CVD) risk factors in individuals with HTN for further management. Few studies in Asian populations have been published to identify the outcome of individuals with HTN and other CVD risk factors. This study aims to assess the effect of HTN alone, and in combination with other CVD risk factors on all-cause and CVD mortality. Three cross-sectional studies carried out in Singapore (baseline 1982--1995) consisting of 5830 persons were grouped by the absence or presence of HTN and CVD risk factors. They were followed-up (mean 14.1 years) by linkage with the National Death Register. Cox's proportional hazards model was used to obtain adjusted hazard ratios (HRs) for risk of mortality. HTN individuals with either <2 CVD risk factors (adjusted HR 1.4; 95% confidence interval (CI) 1.0-1.8) or > or =2 CVD risk factors (adjusted HR 2.3; 95% CI 1.9-3.0) were at increased risk of all-cause mortality compared to normotensive individuals. The findings were similar for CVD mortality. HTN individuals who also smoked or had diabetes were at highest risk of all-cause mortality, whereas those with elevated total cholesterol/high-density lipoprotein cholesterol, smoked or diabetes had the highest risk for CVD mortality. These findings show that in HTN individuals it is important to assess the presence of other CVD risk factors and manage accordingly.