Long-Term Impact of New-Onset Diabetes Mellitus in Hypertensive Patients

BACKGROUND AND OBJECTIVES: Hypertension (HT) is a known risk factor for new-onset diabetes mellitus (NODM), which increases cardiovascular risk. However, the long-term impact of NODM in hypertensive patients remains unclear. METHODS: We analyzed 10,057 hypertensive patients and 109,406 age- and sex-matched non-hypertensive controls from the Korean Hypertension Cohort, followed for over 10 years using National Health Insurance System-Health Screening data. Both cohorts were linked to the National Health Insurance claims database for longitudinal follow-up and outcome assessment. Cox proportional hazards models assessed NODM incidence and its association with major adverse cardiovascular events (MACE) and mortality. RESULTS: The cumulative incidence of NODM was higher in hypertensive patients (8.9% at 2 years, 16.3% at 5 years, and 25.1% at 10 years) than in controls (1.9%, 6.5%, and 14.3%, respectively). The relative risk (RR) of NODM was highest in the first 2 years (RR, 4.55, 95% confidence interval [CI], 4.21-4.90) and remained elevated at 5 years (RR, 2.48) and 10 years (RR, 1.82). Hypertensive patients with NODM had a higher incidence of MACE or death (21.2% vs. 18.7%, RR, 1.21, 95% CI, 1.10-1.32). Most significantly, incidence of post-myocardial infarction heart failure was markedly higher (RR, 4.16, 95% CI, 1.67-10.33). In non-hypertensive individuals, NODM conferred a greater RR for stroke (1.79, 95% CI, 1.23-2.59) than in hypertensive patients. CONCLUSIONS: NODM is highly prevalent in hypertensive patients, particularly early on, and was associated with cardiovascular risk. These findings emphasize the need for early intervention to prevent NODM and its complications in hypertensive individuals.