PURPOSE

To investigate the direct and indirect associations of sleep hygiene with daytime sleepiness, depressive symptoms, and quality of life (QoL), in newly diagnosed, untreated patients with mild obstructive sleep apnea (OSA).

METHODS

Data were collected from adults with mild OSA. The Sleep Hygiene Index (SHI), Sleep Problems Index-1 (SPI-1) of the Medical Outcomes Study-Sleep Scale, Epworth Sleepiness Scale (ESS), Beck Depression Inventory (BDI), and Medical Outcomes Study Short-Form Health survey (SF-36) were used to evaluate patients. To determine the indirect and direct associations between SHI and disease outcomes, the Sobel test and multiple linear regression analyses were used, respectively. When we evaluated the direct associations, we excluded 3 items of the original SHI which were more reflective of general health rather than sleep-specific habits and environments.

RESULTS

In total, 260 patients with mild OSA participated in this study. The average age, AHI, and SHI scores were 49.1 years (SD 12.5), 9.3/h (SD 2.9), and 24.7 (SD 6.0), respectively. Here, ≥ 10% of participants indicated poor sleep hygiene behaviors on 7 of 13 items. Young age and men were associated with higher SHI scores (both p<0.01). The 13-item SHI scores were indirectly related to ESS, BDI, and SF-36 scores via SPI-1 (all p<0.05). The 10-item SHI scores were related to ESS (p=0.049) and SF-36 (p=0.001), but not to BDI, independently of SPI-1 or other confounding factors in mild OSA patients. Age, sex, AHI, and body mass index were not related to ESS, BDI, or total SF-36 scores.

CONCLUSIONS

Sleep hygiene is indirectly related to daytime sleepiness, depressive symptoms, QoL via sleep quality and also related to daytime sleepiness and QoL independent of sleep quality in mild OSA patients.