Impaired sustained attention and lapses are present in patients with mild obstructive sleep apnea

Severe obstructive sleep apnea (OSA) directly affects the quality of life, mood, and sustained attention of individuals, but it has not yet been established in the literature, if these changes also affect patients with mild OSA. The purpose of this study was to investigate such negative effects on the parameters described above.

A controlled study was held at the Universidade Federal de Sao Paulo, Department of Psychobiology. Thirty-nine mild OSA patients and 25 controls were included. Volunteers could be of both genders with body mass index (BMI) ≤35 kg/m(2) and age between 18 and 65 years. Both groups were subjected to full-night polysomnography (PSG), the subjective assessment of mood (Beck Inventory of Anxiety and Depression), Functional Outcomes of Sleep Questionnaire (FOSQ), and the psychomotor vigilance task (PVT) five times during the day. We considered mild OSA patients those with apnea-hypopnea index (AHI) score between 5 and 15. The control group included subjects with AHI scores <5, respiratory disturbance index (RDI) scores ≤5, arousal index values ≤15, and Epworth Sleepiness Scale (ESS) values ≤9.

Mild OSA patients were older and more obese than the controls. After adjusting for age, BMI, and schooling years, there was an increased number of total lapses (3.90 ± 4.16 and 2.43 ± 5.55, p = 0.004).

Patients with mild OSA showed increased sustained attention lapses compared with normal subjects.