Epidemiology of obstructive sleep apnea in older patients with stable cardiovascular disease and chronic kidney disease

Type of funding sources: None.

Obstructive sleep apnea (OSA) is diagnosed late, especially in older people. The presence of chronic hypoxia and glomerular hypertension decrease renal function in patients with OSAS, which causes the progression of chronic kidney disease (CKD) [3]. The aim of the study was to investigate epidemiological aspects of OSA in older patients with stable cardiovascular disease and chronic kidney disease.

80 older patients with stable cardiovascular disease (43 males, mean age was 67.6 ± 6.1 years) were studied. CKD was diagnosed and classified according to the KDIGO guidelines (2012). OSA was observed according to Clinical Guidelines for Obstructive Sleep Apnea and Insomnia (U.S., 2020). Berlin Questionnaire and Epworth Sleepiness Scale, cardiorespiratory monitoring for screening and diagnosis of OSA were used. Follow-up period was 12 months.

Chronic kidney disease was observed in 48 (60%) patients. There were no patients with stages 1 and 2 of CKD, stage 3a was detected in 35 (43.8%), 3b - in 10 (12.5%), stage 4 - in 3 (3.8%) patients. Significant daytime sleepiness was observed in every fourth elderly and senile patient with CKD (12; 25%). A high risk of OSA was observed in the majority of patients with CKD - 34 (70.8%). OSA was first diagnosed in 31 (64.5%) patients with CKD. Moreover, the frequency did not depend on gender (p = 0.39) and age (p = 0.48). There were no differences between elderly (60-74 years old) and senile patients (75-89 years old) in the prevalence of OSAS (p> 0.05).More than half had an average degree of OSA (19; 61.3%). Mild and severe degrees were observed with the same frequency in 6 (19.4%) older patients with CKD. Severity of OSA in men and women did not differ (p> 0.05). The average level of oxygen saturation was higher in men: 93.4 (92.4; 94.15) and 92.3 (91.7; 93.1)%, respectively, p = 0.02. There were no differences in the frequency of OSA detection depending on the stage of CKD (p> 0.05). Only 2 (6.5%) patients with OSA and CKD was consulted a somnologist after 12 months of observation

A high prevalence of OSA was observed in most older patients with stable cardiovascular disease and CKD (34; 70.8%), significant daytime sleepiness was observed in every fourth patient. OSA was first diagnosed in 31 (64.5%) patients with CKD, despite the high risk and clinical symptoms. The severity of OSAS did not depend on gender, age, and the presence of CKD in older patients with stable cardiovascular disease . Subsequently only 2 (6.5%) patients in a sleep consulted, which reflects a low level of overall patient health awareness and availability of quality somnological aid.