Kidney function improves more among women vs men with sleep apnea treatment
Published research suggests women may gain more renal benefits from sleep apnea treatment than men.
“Chronic kidney disease is a growing epidemic worldwide, highlighting the urgency of identifying novel and treatable risk factors,” David D.M. Nicholl, nephrology fellow at Western University, and Sofia B. Ahmed, MD MMSc, FRCPC, of the University of Calgary, Canada, told Healio Nephrology. “Obstructive sleep apnea (OSA) is common in CKD and associated with increased kidney risk. Sleep apnea typically affects more men than women. However, women with sleep apnea are less likely to be diagnosed and treated and may therefore be at increased risk from untreated sleep apnea. We know from our previous work that treatment of OSA with continuous positive airway pressure (CPAP) improved renal hemodynamics and renin angiotensin system activity (a hormone system that is harmful to kidney function), but whether there were sex differences in kidney function in patients with sleep apnea was unknown.”
To investigate, researchers recruited 10 women and 19 men who had obstructive sleep apnea with nocturnal hypoxemia, but no history of kidney disease. All participants were assessed before and after CPAP therapy (used more than 4 hours per night for 4 weeks).
Investigators found CPAP use was associated with improved renal hemodynamics in both women and men. For women, researchers observed increased renal plasma flow, maintained GFR and reduced filtration fraction. In men, CPAP use was associated with maintained renal plasma flow, maintained GFR and reduced filtration fraction.
However, while CPAP downregulated the renin angiotensin system activity in women, this effect was not seen in men.
“Women who are less likely to be diagnosed and treated for sleep apnea may gain more kidney benefits from treatment of sleep apnea than men,” Nicholl and Ahmed said. “This study highlights the importance of studying sex differences in medical conditions and therapies to improve care for all.”
They said larger studies with more men, as well as pre- and post-menopausal women, would help expand this area of research and that future studies should have longer follow-up and consider additional outcomes, including loss of kidney function and need for dialysis or transplant. – by Melissa J. Webb
Disclosures: The authors report no relevant financial disclosures.