SEATTLE, WA—Potassium chloride supplementation might improve the severity of obstructive sleep apnea (OSA) and sleep architecture in hypertensive patients with hypokalemia, according to Nanfang Li, Center for Hypertension, Xinjiang, Urumqi, China.
Speaking at SLEEP 2015, Dr. Lee presented data on a self before-after study designed to explore the potential influence of potassium on OSA. The study was inspired by previous research suggesting that sleep-disordered breathing, sleep disruption, and nocturnal desaturation are common in neuromuscular disease, mainly attributable to weakness of the respiratory muscles. Patients with hypertension who frequently complain of unrefreshed sleep, daytime sleepiness, impaired concentration, fatigue, and lethargy commonly suffer from hypokalemia. Correcting hypokalemia might help maintain sleep architecture and homeostasis. Potassium supplementation might therefore contribute to reduction of sleep-breath events.
The researchers compared 21 hypertensive patients with hypokalemia (mean age 50.6 years and BMI 28.89kg/m2), who underwent polysomnography before and after potassium supplementation to 10 patients who did not receive potassium supplementation.
The mean levels of potassium in the supplementation group were 3.32+0.14mmol/L before supplementation and 4.08+0.28mmol/L following supplementation. There were significant improvements between pre- and post-supplementation AHI [(31.10+21.34) vs. (24.07+17.92) events/hour, P=0.001], apnea index [(13.69+19.74) vs. (9.19+15.72) events/hour, P=0.023], and %REM sleep [(79.98+6.60) minutes, vs. (78.54+ 5.60) minutes, P=0.380]. Patients who did not receive supplementation had similar results on the first and second polysomnography studies.
Dr. Li concluded that this study provided “preliminary evidence” of the potential effectiveness of potassium supplementation in improving OSA severity and sleep architecture in this population. However, she noted, the study was limited by the small number of subjects and the lack of measurement of myoelectric activity of the respiratory muscles.