Sex-specific predictors of the prehypertension-to-hypertension progression: community-based cohort of a West-Asian population

Background: We aimed to predict prehypertension-to-hypertension progression rate among a West-Asian adult population. Methods: We analyzed data on 3449 adults (mean age 41.0 years), prehypertensive at baseline, attending at least one follow-up visit, contributing 25,079 person-years follow-up. A proportional hazard regression analysis was implemented to model the interval-censored progression-free survival time data using readily-assessable, commonly-available information. Integrated discriminatory improvement (IDI) and net reclassification improvement (NRI) indices were calculated to examine whether simple clinical information could help improve prediction of prehypertension-to-hypertension progression rate based on the blood pressure measures. Results: During a median seven-year follow-up 1412 prehypertensive patients progressed to hypertension with annual progression rate (95% confidence intervals (CIs)) being 56.9 (52.9-61.2) per 1000 women and 55.7 (51.7-60.0) per 1000 men (p = 0.007). High-density lipoprotein cholesterol levels were inversely associated with prehypertension-to-hypertension progression rate only among women (hazard ratio (1-SD): 0.93, 95% CIs: 0.86-0.100). Marital status retained its predictability among women even after multivariate adjustments. In both men and women, age, blood pressure measures, waist-to-height ratio, fasting plasma glucose and a history of cardiovascular disease independently predicted prehypertension-to-hypertension rate. The absolute (0.114, 95% CIs: 0.107-0.120) and relative (2.638, 95% CIs: 2.374-2.903) IDI and cutpoint-based (0.213, 95% CIs: 0.156-0.269) and cutpoint-free NRI (0.523, 95% CIs: 0.455-0.591) indicated that the prediction of the prehypertension-to-hypertension progression was improved by multivariable-models compared with blood pressure measures alone. Discussion: Easily-assessable, commonly-available information helped improve predictability of blood pressure measures for prehypertension-to-hypertension progression. Women's psycho-social characteristics (marital status) should be considered in prevention of prehypertension-to-hypertension progression.