Background: OSA is recently recognized as a risk factor for cardiovascular disorders and metabolic syndromes. These syndromes reflect a persistent inciting injury leading to microvascular endothelial dysfunction and one surrogate marker used clinically is urinary urinary albumin excretion. This study evaluates the association of urinary albumin excretion among patients with OSA.
Materials and method: Twenty adults, representing a spectrum of OSA severity, underwent overnight polysomnography and urine collection. OSA severity was assessed using the apneahypopnea index (AHI). The primary outcome measure was the protein-creatinine ratio (PCR). Spearman rank correlations and Chi-square test were used to provide an assessment the realationship between AHI and PCR.
Results: The sample consisted of 20 subjects with a mean age of 50.75 (16.74 SD) years and majority were males (80%) and obese (50%). The percentages of subjects with mild (AHI 5-14), moderate (AHI 15-29, and severe (AHI≥30) were 5%, 25%, 60%, respectively. Results showed that subjects with an AHI of at least 30 did not have any significantly higher mean PCR level than subjects with an HI less than 30. Using the Chi-square test, a p value 0.276 was calculated which was not statistically significant. Likewise, the association of AHI and PCR were not statistically significant (Rs 0.088 p value 0.708.
Conclusion: Our preliminary results demonstrate that the presence of Obstructive Sleep Apnea is not associated with increased urinary albumin excretion. Additional studies with larger population should provide insight into the presence of glomerular endothelial injury in subjects with OSA.