Tables
- TABLE 1
Characteristics unique to females with obstructive sleep apnoea (OSA) or OSA/hypopnoea syndrome (OSAHS) in their clinical presentation, pathophysiology, comorbidities and treatment response compared to males with OSA/OSAHS
Pathophysiology of OSA/OSAHS Upper airway less collapsible Shorter airway length, which increases with age Lower critical closing pressure Subcutaneous and peripheral fat distribution Prolonged partial upper airway obstruction leading to increased respiratory resistance, increased end-tidal CO2 Lower chemoresponsiveness Lower metabolic rate Less respiratory drive instability Progesterone stimulates ventilation Higher CO2 sensitivity and lower upper airway resistance during the luteal phase of menstrual cycle (high progesterone levels) Premenopausal females have lower apnoeic thresholds In pregnancy Reduction in airway size, fluid retention, weight gain, nasal obstruction Reduced functional respiratory capacity and residual volume Increased minute ventilation High progesterone leading to increased upper airway dilator muscle activity Enhanced chemoreceptor responsiveness Right-shifted oxygen dissociation curve Increased maternal heart rate and stroke volume Less time in the supine position Clinical presentation Overall More likely to present with insomnia, mood disturbances, nightmares, fatigue, lack of energy Greater impairment of quality of life Higher healthcare expenditure Higher rate of sick leave, impaired work performance, divorce Hypothyroidism more common Less intense snoring Pregnancy Increased snoring as pregnancy progresses Snoring/OSA associated with pregnancy-induced hypertension, intra-uterine growth retardation, hypertension and diabetes mellitus Menopause Clinical presentation attributed to menopause Doubling of OSA/OSAHS prevalence in menopause Findings on sleep studies (polysomnography/polygraphy) Lower AHI overall Shorter apnoeic episodes More frequent subcriterion events Lower proportion of supine OSA Higher frequency of REM-related OSA Longest apnoeas associated with more severe arterial oxygen desaturation Increased sleep fragmentation in pregnancy Comorbidities More systemic inflammation for given AHI More peripheral and subcutaneous fat distribution premenopausally Pharyngeal collapsibility in females awaiting bariatric surgery correlates with degree of insulin resistance Responses to treatment CPAP trial should be symptom-driven (AHI lower for given clinical symptoms) Lower CPAP pressures more common MRS use may be higher in mild OSA/OSAHS Greater voluntary weight loss sustained, but smaller relative drop in AHI CO2: carbon dioxide; AHI: apnoea–hypopnoea index; REM: rapid eye movement; MRS: mandibular repositioning splints.
Vol 28 Issue 154
Table of Contents
Sex differences in obstructive sleep apnoea
