Sleep Apnea May Raise Cardiovascular Risk in Kidney Transplant Patients
Kidney transplant patients who suffer from obstructive sleep apnea have an increased risk for developing heart-related complications, according to a study published in the Clinical Journal of the American Society of Nephrology (2009; published online ahead of print).
In a cross-sectional study of 100 kidney transplant patients, Miklos Zsolt Molnar, MD, PhD, of Semmelweis University in Budapest, Hungary, and colleagues reported that one out of every four subjects experienced moderate-to-severe obstructive sleep apnea.
Researchers found that the risk of developing heart disease or experiencing a stroke in subjects with obstructive sleep apnea was twice that of patients without the sleep disorder.
In addition, the proportion of renal transplant recipients taking three or more antihypertensive drugs was significantly greater in those with sleep apnea than in those without the condition: 56% versus 31%. Even though the sleep apnea patients took more antihypertensive medications, their average systolic BP remained higher than that of the patients without sleep apnea: 147 versus 139 mm Hg.
The authors explained that total body fat, abdominal circumference, and BMI may increase after transplantation, leading to the high prevalence of sleep apnea in kidney transplant recipients.
Dr. Molnar's group proposes that obstructive sleep apnea is a new risk factor for hypertension and cardiovascular events in kidney transplant recipients. Physicians should routinely screen these patients for obstructive sleep apnea and offer appropriate treatment if it is present, the authors concluded.