Twenty-year secular trends in metabolic comorbidity burden according to hypertension status: Korea national health and nutrition examination survey 2005–2024

Background Korea has achieved substantial improvements in hypertension awareness, treatment, and control over recent decades, representing a notable success in blood pressure management. However, with population ageing and accumulation of metabolic risk factors, clustering of multiple metabolic disorders among individuals with hypertension is emerging as a major challenge. Long-term population-level trends in cumulative metabolic comorbidity burden by hypertension status remain insufficiently characterized. Purpose To investigate 20-year secular trends in the prevalence and clustering of metabolic comorbidities according to hypertension status using nationally representative data from Korea. Methods We analyzed 79,182 adults aged 30–79 years from the Korea National Health and Nutrition Examination Survey 2005–2024. Hypertension status was categorized as hypertension, prehypertension, or normal blood pressure based on Korean Society of Hypertension guidelines. Five metabolic comorbidities were assessed: obesity, diabetes mellitus, dyslipidemia, chronic kidney disease, and fatty liver. Survey weights were applied to generate nationally representative estimates. Trends in comorbidity prevalence and cumulative burden were examined by hypertension status. Multivariable logistic regression models estimated adjusted odds ratio (OR) and confidence interval (CI) for individual comorbidities and multimorbidity (≥2 and ≥3 conditions), adjusting for demographic and behavioral factors. Results The mean age was 50.5 years, and 55.8% were women. Overall, 29.8% had hypertension, 25.9% prehypertension, and 44.3% normal blood pressure. Across survey cycles, all metabolic comorbidities were consistently more prevalent in the hypertension group than in the normal group. Diabetes mellitus and dyslipidemia showed sustained increases among hypertensive individuals, whereas chronic kidney disease declined mid-period and rose again in recent cycles. The proportion of hypertension increased progressively with higher comorbidity counts, indicating growing concentration of multimorbidity within the hypertensive group. Of the five metabolic comorbidities, fatty liver was most strongly associated with hypertension (OR 6.62; 95% CI 6.13–7.15). Multimorbidity was markedly elevated in the hypertension group (OR 4.48; 95% CI 4.25–4.73 for ≥2 conditions; OR 6.23; 95% CI 5.78–6.70 for ≥3 conditions). Prehypertension was also associated with increased comorbidity burden. Conclusion Despite major progress in hypertension control, metabolic multimorbidity has increasingly clustered among individuals with hypertension over the past two decades in Korea. Future prevention strategies should extend beyond blood pressure control to integrated management of multiple metabolic conditions beginning at the prehypertension stage.