Sex differences in hypertension incidence and risk factors: a population-based cohort study in Southern Iran

Abstract

Background: Hypertension (HTN) is a major global public health concern. This study aims to identify gender differences to inform more effective prevention strategies and targeted management approaches.

Methods: This prospective cohort study included 7,710 participants aged 40 to 70 years, with a mean follow-up duration of 5.2 years. HTN was defined using European hypertension management guidelines. A Cox regression model was employed to determine factors associated with HTN, adjusting for confounding variables effects.

Results: During the mean follow-up period of 5.2 years, the incidence rate of hypertension was 21.54 per 1,000 person-years, with females exhibiting a higher incidence than males. Several significant predictors of HTN were identified. In men, key risk factors included age (60-70 years, 2.83-fold increase, 95% CI 2.05-3.92), high waist-to-height ratio (5.63-fold increase, 95% CI 2.42-13.07), smoking (2.68-fold increase, 95% CI 1.04-6.91), and opium use (1.93-fold increase, 95% CI 1.06-3.49). In women, significant predictors included age (60-70 years, 3.65-fold increase, 95% CI 2.59-5.15), contraceptive drug use (1.24-fold increase, 95% CI 1.01-1.52), high waist-to-height ratio (1.87-fold increase, 95% CI 1.19-2.92), pre-HTN (3.64-fold increase, 95% CI 3.01-4.40), and kidney stones (1.32-fold increase, 95% CI 1.06-1.65).

Conclusion: This study identified key predictors of hypertension (HTN) with notable gender differences. For men, significant risk factors included age, high waist-to-height ratio, smoking, and opium use; for women, the prominent predictors were age, contraceptive use, pre-HTN, and kidney stones. These findings highlight the need for gender-specific strategies in HTN prevention and management, focusing on modifiable risk factors by gender.

Keywords: Cohort study; Hypertension; Incidence; Risk factors; Sex.

Fig. 1

Flow chart for the enrollment process of study and Prevalence of studied variables among male and female in baseline

Fig. 2

Kaplan–Meier curves for HTN-free survival by gender. (The Kaplan–Meier survival curve demonstrates stabilization beyond the 60-month time point, despite a significant reduction in the number of participants at risk. This pattern can be explained by the study design, in which participants were enrolled over a two-year period. Consequently, some participants had follow-up durations shorter than 60 months and were censored at the end of their respective observation periods. The decrease in the number at risk after 60 months is thus a result of censoring, rather than an increase in event occurrences. The stabilization of the survival curve during this time frame likely reflects a low incidence of events among the remaining cohort)

Fig. 3

A predictors of incident hypertension in male. B predictors of incident hypertension in female

Fig. 4

Risk factors of hypertension by sex