Conference Coverage

OSA With Worsening Hypoxemia Raises Risk of Metabolic Syndrome

Older age and increased BMI also heighten the risk of incident metabolic syndrome.


BALTIMORE—Patients with obstructive sleep apnea (OSA) who are prone to worsening of hypoxemia at night have a heightened risk of developing metabolic syndrome, according to an eight-year cohort study described at the 32nd Annual Meeting of the Associated Professional Sleep Societies.

“Considering that we have a very high prevalence of moderate to severe OSA in the general population, this is a very important finding because it indicates that we need some clinical options for treating OSA in those that have metabolic syndrome to decrease the risk of morbidity and mortality and cardiac events,” said Camila Hirotsu, PhD, of the Federal University of São Paulo, Brazil.

Camila Hirotsu, PhD

Dr. Hirotsu presented eight-year follow-up results of the EPISONO cohort, an observational prospective study conducted in Brazil, the goal of which was to evaluate how OSA can affect the risk of developing metabolic syndrome in the general population. Metabolic syndrome is defined as a cluster of three or more of the following cardiovascular metabolic components: low HDL levels, high glucose and triglyceride levels, hypertension, and abdominal obesity. Between 50% and 60% of patients with metabolic syndrome have OSA, said Dr. Hirotsu.

The study enrolled 1,074 patients at baseline, and enrollment ended in 2008. The researchers obtained follow-up on 712 participants, who were evaluated from July 2015 to April 2016. After exclusions, the study evaluated 476 patients who were free of metabolic syndrome at baseline. Of this sample, 44% subsequently developed metabolic syndrome.

The median age of patients who developed metabolic syndrome was 40.8 versus 36.1 for those who did not. Patients who developed metabolic syndrome also had a higher BMI, but were not obese, compared with the other participants (26.9 kg/m2 vs 23.8 kg/m2). Patients completed questionnaires and underwent full polysomnography and clinical assessments.

For patients with moderate to severe OSA, the odds ratio (OR) of developing incident metabolic syndrome was 2.47, said Dr. Hirotsu. Rates of moderate to severe OSA were 21.3% for the group that developed metabolic syndrome versus 9% for the group that did not.

Apnea–hypopnea index (OR, 1.16), 3% oxygen desaturation index (OR, 1.24), and time with oxygen saturation by pulse oximeter less than 90% (OR, 1.42) were associated with incident metabolic syndrome, according to the researchers.

“Moderate to severe OSA at baseline and worsening of nocturnal hyperemia from baseline to follow-up are really independent risk factors to increase the incidence of metabolic syndrome in the general population,” said Dr. Hirotsu.

A secondary aim of the study was to evaluate the impact of metabolic syndrome on the risk of developing OSA in the general population. “It seems that metabolic syndrome is not really an independent risk factor for OSA,” Dr. Hirotsu said.

—Richard Mark Kirkner

Suggested Reading

Drager LF, Lopes HF, Maki-Nunes C, et al. The impact of obstructive sleep apnea on metabolic and inflammatory markers in consecutive patients with metabolic syndrome. PLoS One. 2010;5(8):e12065.

Next Article:

Light Exposure During Sleep May Increase Insulin Resistance

Related Articles