Objectives Obstructive apnoeas during sleep are associated with marked cycl
ical blood pressure fluctuations in men with obstructive sleep apnoea (OSA)
. Haemodynamic responses to OSA in women are largely unknown. We aimed to i
nvestigate haemodynamics during apnoeic events in women with OSA and to ass
ess the influence of the menstrual cycle on these responses.
Design and methods Full overnight polysomnography and continuous non-invasi
ve blood pressure monitoring was performed in 13 women with OSA during foll
icular and luteal phases of the menstrual cycle. Change in blood pressure (
Delta BP) from pre- to post-apnoea termination was measured for each apnoei
c cycle.
Results Only 10 of 13 subjects ovulated. In women who ovulated, presser res
ponses to apnoea termination occurred in both non-rapid eye movement (NREM)
and rapid eye movement (REM) sleep, but substantially increased during the
luteal phase of ovulatory cycles [NREM change in mean arterial pressure (D
elta MAP) 12 +/- 3 mmHg during the follicular phase and 20 +/- 3 mmHg durin
g the luteal phase, P < 0.001; REM Delta MAP 11 +/- 3 mmHg during the folli
cular phase and 23 +/- 3 mmHg during the luteal phase, P < 0.001]. Sleep ap
noea severity did not change during the cycle in NREM sleep, but was reduce
d in REM during the luteal phase. Changes in presser responses were absent
in non-ovulating subjects.
Conclusions Obstructive apnoeas in women were associated with marked blood
pressure changes, similar to those previously reported in men. While respir
atory events improved slightly in the luteal phase, blood pressure response
s to these events increased by approximately 100%. Thus, the menstrual cycl
e has discordant effects on the respiratory and cardiovascular effects of O
SA in women. J Hypertens 1999, 17:603-610 (C) Lippincott Williams & Wilkins
.