High prevalence of unrecognized sleep apnoea in drug-resistant hypertension

J Hypertens. 2001 Dec;19(12):2271-7. doi: 10.1097/00004872-200112000-00022.


Objectives: To determine the prevalence of obstructive sleep apnoea (OSA) in adult patients with drug-resistant hypertension, a common problem in a tertiary care facility.

Design: Cross-sectional study.

Setting: University hypertension clinic.

Patients and methods: Adults with drug-resistant hypertension, defined as a clinic blood pressure of > or = 140/90 mmHg, while taking a sensible combination of three or more antihypertensive drugs, titrated to maximally recommended doses. Each of the 41 participants completed an overnight polysomnographic study and all but two had a 24 h ambulatory blood pressure measurement.

Results: Prevalence of OSA, defined as an apnoea-hypopnoea index of > or = 10 obstructive events per hour of sleep, was 83% in the 24 men and 17 women studied. Patients were generally late middle-aged (57.2 +/- 1.6 years, mean +/- SE), predominantly white (85%), obese (body mass index, 34.0 +/- 0.9 kg/m2) and taking a mean of 3.6 +/- 0.1 different antihypertensive medications daily. OSA was more prevalent in men than in women (96 versus 65%, P = 0.014) and more severe (mean apnoea-hypopnoea index of 32.2 +/- 4.5 versus 14.0 +/- 3.1 events/h, P = 0.004). There was no gender difference in body mass index or age. Women with OSA were significantly older and had a higher systolic blood pressure, lower diastolic blood pressure, wider pulse pressure and slower heart rate than women without OSA.

Conclusions: The extraordinarily high prevalence of OSA in these patients supports its potential role in the pathogenesis of drug-resistant hypertension, and justifies the undertaking of a randomized controlled trial to corroborate this hypothesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antihypertensive Agents / therapeutic use*
  • Cross-Sectional Studies
  • Drug Resistance
  • Drug Therapy, Combination
  • Female
  • Humans
  • Hypertension / drug therapy*
  • Hypertension / etiology*
  • Male
  • Middle Aged
  • Obesity / complications
  • Prevalence
  • Sleep Apnea Syndromes / complications*
  • Sleep Apnea Syndromes / epidemiology*


  • Antihypertensive Agents