Prevalence and prognostic significance of untreated, uncontrolled and resistant hypertension among American adults...

Background: The prevalence of untreated, uncontrolled and resistant hypertension and their specific prognosis among American adults with prediabetes remain unclear. We aimed to explore the prevalence of hypertension treatment and control and their associated risks of all-cause and cardiovascular disease (CVD) mortality among this population. Methods: We analysed data from 12,321 participants in the National Health and Nutrition Examination Survey (NHANES) survey (1999-2016). Prediabetes was defined as a fasting plasma glucose (FPG) of 5.6-7.0 mmol/L, a haemoglobin A1c of 5.7-6.4%, a 2-h plasma glucose of 7.8-11.1 mmol/L or self-reported diagnosis. Hypertension was defined as blood pressure (BP) ≥140/90 mmHg, a self-reported history of hypertension, or current antihypertensive medication use, and categorized into untreated, controlled, uncontrolled and resistant hypertension. Cox regression was used to assess associations between hypertension categories and both CVD and all-cause mortality. Results: The study included 12,321 adults with prediabetes, representing an estimated 53.3 million individuals. Age- and sex-standardised hypertension prevalence was 43%. Among those with hypertension, 62% were receiving treatment. Among treated individuals, 66% had controlled hypertension, 26.5% had uncontrolled hypertension and 7.5% had resistant hypertension. Mortality risk increased progressively from non-hypertensive to untreated, controlled, uncontrolled and resistant hypertension stages. Compared to non-hypertensive individuals, hazard ratios (HRs) for CVD mortality were 1.17 (95% CI: 0.80-1.71), 1.52 (1.04-2.21), 2.03 (1.35-3.05) and 1.83 (1.07-3.13), respectively (P for trend <0.001). For all-cause mortality, HRs were 1.01 (0.86-1.20), 1.05 (0.87-1.26), 1.16 (0.95-1.41) and 1.42 (1.09-1.85), respectively (P for trend = 0.022). Conclusions: Hypertension was highly prevalent among American adults with prediabetes, and mortality risk increased with advancing hypertension stages.