Increased urinary IgM excretion in patients with obstructive sleep apnea

Area of Science:

• Nephrology
• Sleep Medicine
• Cardiovascular Research

Background:

• Obstructive sleep apnea (OSA) is associated with intermittent hypoxemia, potentially causing renal endothelial injury.
• Limited evidence exists on urinary immunoglobulin M (IgM-uria) in OSA patients.
• This study investigates the link between OSA severity and urinary IgM and albuminuria in diabetic and non-diabetic individuals.

Purpose of the Study:

• To evaluate the association between obstructive sleep apnea severity and urinary IgM and albuminuria.
• To compare these associations in non-diabetic versus diabetic patients.

Main Methods:

• A cross-sectional study involving 124 adults who underwent polysomnography.
• Urine samples were analyzed for IgM and albumin, normalized to creatinine.
• Multivariable linear regression models were used, adjusting for confounders and testing for interactions with diabetes status.

Main Results:

• In non-diabetic participants, decreased mean SpO2 and increased oxygen desaturation index and apnea-hypopnea index were significantly associated with higher urinary IgM-uria and albuminuria.
• These associations were not significant in diabetic patients.
• Urinary IgM and albumin correlated with OSA severity in non-diabetics.

Conclusions:

• Urinary IgM and albumin levels are associated with OSA severity in non-diabetic individuals.
• These markers may act as cost-effective, non-invasive biomarkers for glomerular injury in sleep apnea.
• Further longitudinal research is needed to confirm reversibility with OSA treatment.