A new study indicates that the amino acid cysteine may be a biomarker for the development of obstructive sleep apnea (OSA) in obese and nonobese patients.
Brazilian researchers compared plasma levels of cysteine in 75 patients with OSA with 75 control subjects.
Results showed that cysteine plasma levels were higher in patients with OSA compared with the control subjects. A subgroup of lean patients (BMI < 25) with OSA also had higher cysteine levels than the control subjects. Furthermore, patients with OSA who received continuous positive airway pressure showed a decrease in plasma levels of cysteine after 6 months.
Researchers conclude that cysteine is a potential biomarker for OSA and that obesity does not influence its function as a biomarker. The article is published in the February issue of Chest, the peer-reviewed journal of the American College of Chest Physicians.