Prevalence and factors associated with hypertension among individuals undergoing premarital examination in Guangxi, China: a large cross-sectional study, 2022–2024

Background Hypertension constitutes a leading global public health challenge, with early detection in young adults critical for primordial and primary prevention. Premarital health examinations represent an underutilized platform for population-based cardiovascular screening. This study aimed to estimate the prevalence of hypertension and identify associated factors among individuals undergoing premarital examination in Guangxi, China. Methods This large cross-sectional study was conducted at the Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region from 2022 to 2024, enrolling 11,283 consecutive premarital participants aged 20–50 years (5,641 males, 5,642 females). Sociodemographic, anthropometric, and metabolic indicators were collected using standardized questionnaires, physical measurements, and fasting biochemical tests. According to local premarital health policy, fasting blood glucose was measured only in female participants. Hypertension was defined as SBP ≥ 140 mmHg and/or DBP ≥ 90 mmHg, or self-reported physician-diagnosed hypertension. Univariate tests, multivariate logistic regression and restricted cubic spline (RCS) models were applied to identify correlates and dose–response relationships. Results The overall prevalence of hypertension was 7.68%, with a significantly higher rate in men (10.28%) than in women (5.09%). In univariate analysis, age, body mass index (BMI), fasting blood glucose (FBG), alanine aminotransferase (ALT), sex, BMI classification, alcohol drinking, education level, abnormal FBG, and abnormal ALT were significantly associated with hypertension in the total population (all p < 0.05). Multivariate regression identified overweight (OR = 1.88, 95%CI: 1.27–2.77, p = 0.002), obesity (OR = 3.90, 95%CI: 2.29–6.64, p < 0.001), lower education level (OR = 1.64, 95%CI: 1.13–2.38, p = 0.009), abnormal ALT (OR = 1.69, 95%CI: 1.12–2.56, p = 0.013) and annual age increment (OR = 1.04, 95%CI: 1.01–1.08, p = 0.011) as factors associated with higher odds of hypertension, while underweight was associated with lower odds (OR = 0.42, 95%CI: 0.19–0.93, p = 0.033). In sex-stratified analyses, abnormal fasting blood glucose was independently associated with higher odds of hypertension in women (OR = 1.96, 95%CI: 1.21–3.16, p = 0.006). RCS analyses confirmed positive dose–response correlations between BMI, ALT, age and the odds of hypertension (all P for overall <0.05). Conclusion Hypertension imposes a non-negligible health burden among premarital adults in Guangxi, with a markedly higher prevalence observed in males. Overweight, obesity, elevated liver enzyme levels, low educational attainment, advancing age, and abnormal fasting glucose (in women) are key correlates of hypertension in this population. Routine premarital health services should integrate comprehensive cardiovascular risk screening covering blood pressure measurement and BMI assessment, with targeted health education, to support long-term cardiovascular health among young reproductive-age populations.