Proteinuria in patients with sleep apnea.
BACKGROUND
Proteinuria severe enough to be in the nephrotic range has been noted on occasion in patients with obstructive sleep apnea (OSA), but it is not known what factors are related to the severity of proteinuria in these patients. This study was conducted to determine if the severity of proteinuria is related to the number of apneas.


METHODS
The level of proteinuria was determined by the dipstick method in 407 patients in whom OSA had been diagnosed. The apnea-hypopnea index (AHI) was calculated in each patient after all-night polysomnography. Sleep apnea was defined as the presence of at least 30 apneas during a 6- to 8-hour monitoring period and an AHI greater than 15.


RESULTS
The apnea-hypopnea index in patients without proteinuria was similar to that of patients with 1+ to 3+ proteinuria. However, the AHI was significantly greater in the 9 patients with 4+ proteinuria.


CONCLUSIONS
While severe proteinuria in OSA occurs in patients with a higher rate of sleep apneas, the lesser degree of proteinuria cannot be explained by AHI alone. Other factors that determine the severity of the disease, such as hypoxemia, merit further investigation.
Chaudhary
B A
BA
Georgia Sleep Center, Medical College of Georgia, Augusta 30912-3137.
Rehman
O U
OU
Brown
T M
TM
D000328:Adult; D006801:Humans; D017286:Polysomnography; D011507:Proteinuria / Q000175:diagnosis / Q000652:urine*; D012891:Sleep Apnea Syndromes / Q000175:diagnosis / Q000652:urine*