Long-term gender-specific evolution of blood pressure under CPAP therapy in hypertensive patients with obstructive sleep apnea syndrome.

INTRODUCTION

Reduction of blood pressure (BP) under CPAP treatment in patients with obstructive sleep apnea syndrome (OSAS) associating hypertension (HT) is controversial and short-term evolution is often measured using the sphygmomanometer.

PURPOSE

To study the variation in BP (sphygmomanometer and Holter) after 3 and 6 months of CPAP in OSAS patients associating hypertension.

METHODS

We applied the exclusion criteria (hypoventilation, respiratory diseases, secondary hypertension, antihypertensive treatment modification during study, non-compliance) on 96 consecutive patients (SPSS 17.0: Chi test, T-test).

RESULTS

15 hypertensive patients (8.53 years from diagnosis) with OSAS succeeded six months of following: 3 women (20%), 12 men (80%) were comparable as age, body mass index and Epworth score; women had more severe OSAS. Sphygmomanometer measuring in men showed a decrease in systolic BP (SBP) (142 ± 8.9 to 128.7 ± 11.7 mmHg, p = 0.005) and diastolic BP (DBP) (82 ± 17.19 to 69.1 ± 6.6 mmHg, p = 0.040) at three months of treatment. Women had no changes at 3 and 6 months of assessment using the sphygmomanometer. BP Holter showed no significant changes in men; women exhibit a significant increase in maximum DBP/24 hours (104 ± 13.4 to 169.5 ± 27.5 mmHg, p = 0.034) and mean daytime DBP/24 hours (100 ± 14.1 to 166 ± 32.5 mmHg, p = 0.046) from 3 to 6 months. No group presents dipper status change to 3 or 6 months.

CONCLUSIONS

The trend in both groups of increase in BP for 3 to 6 months is explained by the natural evolution of an old HT history. Long time monitoring using Holter device is more accurate in assessing cardiovascular risk.