Evidence for a relationship between sleep disorders and severity of hypertension in uncontrolled hypertensive patients

Abstract

Objectives: Questions have been recently added to assess the potential relationships between sleep disorders, sleep duration and sleep quality on the one hand, and prevalent conditions such as arterial hypertension (HTN) and diabetes on the other hand. Prior overview surveys found increased risk in hypertensive vs normotensive adults having concurrent sleep disorders with poor or short sleep. The current study looks more closely in regard to HTN control, to assess the existence of any correlation between sleep disorders and severity of HTN (defined by ESH stages) in a large cohort of uncontrolled hypertensive outpatients. Methods: Cross sectional epidemiological study conducted in France in outpatients visiting cardiologists. Each physician included the first 4 hypertensive patients whose blood pressure was not controlled (>140/90 mmHg) by their current antihypertensive treatments regardless of these treatments. Symptoms of sleep apnea were collected and patients were requested to complete the Athens Insomnia Scale (AIS) and Epworth sleepiness score. Results: A total of 1,447 patients, median age 65 years among whom 62.8% were males and 39.1% were obese were included. 34.5% had stage I hypertension, 53.1% had stage II hypertension and 12.4% had stage III hypertension. The mean number of antihypertensive drugs was 1.9+1.0 (min/max:1-6). Mean Epworth score was 7.8+5.2 and mean AIS was 7.7+4.5. The prevalence of sleepiness was 37.0% in stage I hypertension, 43.4% in stage II hypertension and 43.8% in stage III hypertension and the insomnia rates respectively 52.6%, 55.5% and 63.4%. The polytomous logistic regression analysis adjusted on all patient characteristics (age, sex, BMI, duration of hypertension, cardiovascular risk factors, associated cardiovascular diseases, current antihypertensive drugs) showed that the existence of an Epworth score > 8 increased by 1.5 the risk of having hypertension stage 3 rather than stage 1 (p=0.0241) and that an AIS > 6 increased by 1.8 the risk of having a stage 2 hypertension rather than stage 1 (p: 0.0265). The Epworth sleepiness score appeared more discriminating than the insomnia AIS score. Conclusion: Results from this large <<real-life>> cohort of uncontrolled hypertensive outpatients confirm the close relationship between sleep disorders and severity of HTN. These conclusions should encourage physicians to systematically include the detection of sleep disorders in hypertensive patients and especially when HTN is uncontrolled.