Clinical presentation of obstructive sleep apnea in patients with chronic kidney disease.
BACKGROUND
Obstructive sleep apnea (OSA) is an important and common comorbidity in patients with chronic kidney disease (CKD). However, few studies have addressed how OSA presents in this patient population and whether it is clinically apparent.


OBJECTIVE
The objectives of this study were to determine if the prevalence and severity of sleep related symptoms distinguished CKD patients with OSA from those without apnea, and whether the clinical presentation of OSA in CKD patients differed from the general OSA population.


METHODS
One hundred nineteen patients were recruited from outpatient nephrology clinics. All patients completed a sleep history questionnaire, the Epworth Sleepiness Scale (daytime sleepiness, ESS > 10), the Pittsburgh Sleep Quality Index (poor sleep quality, PSQI > 5), and underwent overnight cardiopulmonary monitoring for determination of sleep apnea (respiratory disturbance index ≥ 15). CKD patients with OSA (n = 46) were compared to (1) CKD patients without OSA (n = 73) and (2) OSA patients without CKD (n = 230) who were referred to the sleep centre.


RESULTS
The prevalence of OSA symptoms and PSQI scores did not differ between CKD patients with OSA and CKD patients without apnea. Although the prevalence of daytime sleepiness was higher in CKD patients with OSA compared to CKD patients without apnea (39% vs. 19%, p = 0.033), both daytime sleepiness and other symptoms of sleep apnea were considerably less frequent than in OSA patients without a history of kidney disease.


CONCLUSIONS
The presence of OSA in patients with CKD is unlikely to be clinically apparent. Consequently, objective cardiopulmonary monitoring during sleep is required to reliably identify this comorbidity.
Department of Medicine, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada.
David D M
DD
Nicholl
Sofia B
SB
Ahmed
Andrea H S
AH
Loewen
Brenda R
BR
Hemmelgarn
Darlene Y
DY
Sola
Jaime M
JM
Beecroft
Tanvir C
TC
Turin
Patrick J
PJ
Hanly
D000368:Aged; D015897:Comorbidity; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010092:Oximetry; D017286:Polysomnography; D015995:Prevalence; D051436:Renal Insufficiency, Chronic / Q000453:epidemiology*; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000453:epidemiology*; D011795:Surveys and Questionnaires; D014851:Wakefulness