Substances use and risk of hypertension before midlife in military young adults: CHIEF cohort study, 2014–2020

Background

The use of substances, e.g., tobacco and betel nut, are prevalent among military personnel in Taiwan, whereas some specific substances such as alcohol use are forbidden in military base. There were inconsistent findings for the incidence of hypertension with habitual substances use in diverse populations, while no studies were carried out in the military.

Methods

A total of 2419 Taiwanese military personnel, aged 18–39 years, who were not taking any antihypertensive agents and did not have a baseline systolic blood pressure (SBP) ≥130 mmHg and/or diastolic blood pressure (DBP) ≥80 mmHg were followed for incidence of hypertension from baseline (2014) through the end of 2020. Alcohol, tobacco and betel nut use status (active vs. former/never) were self-reported by each participant at baseline. New-onset hypertension of each participant was defined by an average of two resting BP measurements in the annual health examinations (2015–2020). Multivariable Cox regression analysis with adjustments for baseline BP and other potential covariates were performed to determine the risk of incident hypertension with each substance use. Five-year absolute changes in BP level with specific substance use were compared using analysis of covariance (ANCOVA).

Results

There were 867 active smokers (35.8 %), 237 active betel nut chewers (9.8 %) and 961 active alcohol consumers (39.7 %) at baseline. During a median follow-up of 5.8 years, 911 new-onset hypertension events (37.7 %) were observed. While compared to those without any substances use, merely active holiday alcohol users had a significantly lower risk of incident hypertension [hazard ratio (HR) and 95 % confidence interval: 0.72 (0.58–0.89)]. The 5-year diastolic BP increase (mmHg) was borderline significantly lower in active alcohol users on holidays as compared to former/never alcohol users (4.02 (standard deviation =9.01) and 4.76 (9.42), p = 0.07). The risk of incident hypertension was not significant in active smokers and active betel nut users, while the 5-year BP increase level was significantly greater in active smokers than former/never smokers (5.60 (9.96) vs. 4.42 (9.22), p = 0.03).

Conclusion

Our findings suggest that military young personnel consuming alcohol only allowed on holidays had a lower incidence of new-onset hypertension. On the contrary, the 5-year BP change may increase greater with habitual smoking, though the risk of new-onset hypertension was not affected.