Obstructive sleep apnea need not be severe in order to heighten risk of hypertension, as individuals in a population-based study with mild, even asymptomatic sleep apnea still had a fourfold increase in rates, a researcher said here.
But the risk was largely confined to people in their 20s, 30s and 40s, reported Alexandros N. Vgontzas, MD, of Penn State University College of Medicine in Hershey, Pa., at the 2017 SLEEP meeting, jointly sponsored by the American Academy of Sleep Medicine and the Sleep Research Society.
Among 20-year-olds with normal blood pressure at baseline, mild obstructive sleep apnea (OSA) was associated with a 90% increased risk for developing hypertension during 10 years of follow up, and among 30-year-olds, mild OAS was associated with an 80% increase in hypertension risk, Vgontzas told MedPage Today.
He added that having mild OSA was associated with a negligible increase in hypertension risk over 10 years of follow up in people who were age 65 and older.
Vgontzas said the study findings suggest that efforts to reduce hypertension risk among people with mild to moderate OSA should focus on younger adults, but he added that this doesn’t necessarily mean that these largely asymptomatic people should be treated with continuous positive airway pressure (CPAP) therapy.
“Our subanalysis also showed a high correlation between mild to moderate sleep apnea in younger people and obesity and metabolic syndrome,” Vgontzas said, adding that informing younger patients with these risk factors about their risk for hypertension and recommending lifestyle interventions such as weight loss and exercise could be an effective strategy for reducing hypertension risk in this population.
“If they already have high blood pressure, they may need to be on CPAP, but, if not, it is probably not needed,” he said.
According to the American Academy of Sleep Medicine, nearly 30 million adults in the U.S. have OSA, and Vgontzas said between 15% and 30% have mild to moderate OSA, meaning that they stop breathing for 10 seconds or more between 5 and 30 times an hour during sleep.
Severe sleep apnea, which involves more than 30, 10-second or more breathing stops per hour, is a well recognized risk factor for developing hypertension, but the previous research examining the impact of mild-to-moderate OSA on high blood pressure risk has been mixed.
The newly reported study included a random sample of 1,741 adults who underwent an overnight polysomnography study and provided a detailed medical history at baseline as participants in the Penn State Adult Cohort study.
Follow-up included 797 study participants followed for 10 years who did not have hypertension when they entered the study.
Mild and moderate OSA were defined as Apnea Hypertension Index scores of 5-14.9 and 15-29.9, respectively. The presence of hypertension at baseline and follow-up was identified by a self-report of receiving treatment for hypertension and/or history of a hypertension diagnosis.
The overall incidence of hypertension was 25.2% at follow-up. After adjusting for sex, race, baseline age, BMI, hormone replacement therapy, smoking, alcohol drinking, MAP, apnea therapy and length of follow-up, mild and moderate OAS were significantly associated with an increased risk for developing hypertension (mild OSA, OR 4.35, 95% CI 2.25-8.39; moderate OSA, OR 3.80, 95% CI 1.41-10.30).
Vgontzas concluded that future studies should examine the potential of biomarkers to improve clinicians’ abilities to predict who, among asymptomatic patients with mild-to-moderate OSA, are at increased risk of adverse cardiometabolic sequelae in the future.
“In young and middle-aged adults, our findings suggest that early detection and treatment of mild-to-moderate sleep apnea is warranted in order to prevent future cardiometabolic disease,” study co-author Yun Li, MD, also of Penn State, said in a written press statement.
Li said that given the stronger association of sleep apnea and metabolic abnormalities in this younger age group, “emphasis should be placed on yearly monitoring of indices of metabolic syndromes and lifestyle interventions, such as weight control, healthy diet, regular exercise and stress management.”