OSA in Patients With Hypertension Increases Risk for Chronic Kidney Disease

Patients with hypertension with obstructive sleep apnea (OSA) have an increased risk of developing chronic kidney disease (CKD), according to study findings published in the journal Sleep Medicine.

Research has shown that individuals with hypertension are at higher risk for CKD; however, the effect of OSA on the kidneys in this population is unknown.

Therefore, researchers conducted a longitudinal cohort study to assess whether OSA was a risk factor for kidney damage among patients with hypertension.

Participants were adults with hypertension with suspected OSA who underwent polysomnography testing between January 2011 and December 2018. Baseline data collected from electronic health records included demographics, sex, blood pressure, and body mass index (BMI).

The main renal outcome was new-onset CKD, defined as an estimated glomerular filtration rate (eGFR) of less than 60 mL/min per 1.73 m² and/or the presence of proteinuria, during follow-up.

Of 9,704 participants, 7,961 had hypertension (5022 with OSA) and were included in the analysis. The majority of the total participants were men (63.0%) and aged 45 years and older (67.6%). 

During a median follow-up of 3.42 years, 1,486 patients developed CKD at an incidence rate of 51.69 per 1,000 person-years.

Compared with patients with hypertension without OSA, those with hypertension and OSA and severe OSA had a 1.21 (95% CI, 1.08-1.35) and 1.27 (95% CI, 1.09-1.47) increased risk of developing CKD, respectively. Patients with hypertension with vs without OSA also had a higher risk for decreased kidney function (hazard ratio [HR], 1.38; 95% CI, 1.16-1.63; P <.001) and proteinuria (HR, 1.12; 0.97-1.28; P =.118), which was not statistically significant in the fully adjusted models.

The researchers observed that patients with hypertension and OSA with a BMI of 24 and greater had an increased risk for CKD, decreased kidney function, and proteinuria (HRs, 1.26; P <.001, 1.32; P =.002, and 1.24; P =.003, respectively).

Study limitations included the lack of generalizability; that all sleep measures were not considered; potential selection bias; and the possibility of errors in the measurement of kidney function.

The researchers concluded, “[I]t is of significance to conduct routine renal function screening for patients with OSA, especially in population with hypertension.”