The prevalence of individuals at high risk of true resistant hypertension and obstructive sleep apnoea in a New Zealand cohort.

AIMS To determine the prevalence of individuals at high risk of true resistant hypertension (tRHT) in Dunedin-based adults <60 years diagnosed with hypertension and pharmacologically managed with three or more antihypertensive medications (ie, apparent resistant hypertension (aRHT)); to describe characteristics of those with aRHT; and to investigate the association between tRHT and obstructive sleep apnoea in the group. METHODS Participants with aRHT were recruited and data collected using standardised equipment and methodology. Characteristics were reported using descriptive statistics. The proportion (with 95% confidence intervals) of individuals at high risk of tRHT in individuals with aRHT was calculated. RESULTS Twenty-five aRHT individuals participated (17 males; group mean age 51.8±8.9 years; body mass index 33.6±6.2 kg/m2). Measures (mean ±SD) for neck circumferences for males were 41.9±4.9cm, females 37.3±3.1cm; waist circumferences for males were 108.4±15.2cm, females 105.2±17.3cm. Group systolic and diastolic 24h ambulatory blood pressure (mmHg) were 148.9±20.5 (95% CI: 140.4 to 157.4), 88.2±14.6 (95% CI: 82.2 to 94.2); office blood pressure were 140.8±18.3 (95% CI: 133.2 to 148.3), 83.5±12.1 (95% CI: 78.5 to 88.5). The prevalence of individuals at high risk of tRHT was 88% (95% CI: 69% to 98%); proportion of obstructive sleep apnoea (OSA) risk among tRHT group was 86% (95% CI 65% to 97%). CONCLUSIONS The prevalence of individuals at high risk of both tRHT and OSA risk was large in Dunedin-based adults diagnosed with aRHT. Anthropometric assessments indicated high abdominal and visceral adiposity. Group mean blood pressure values exceeded New Zealand's hypertension diagnostic value, suggesting uncontrolled RHT.