This study had a sample of 136 patients with OSA, and their bed partners were more likely to report sleep disturbance. Nevertheless, the frequency of apnea–hypopnea and snoring resulting from OSA did not negatively affect the sleep quality of bed partners. Self-reported depressive symptom scores and the prevalence of chronic disease were higher in bed partners with sleep disturbance. Additionally, bed partner–reported depressive symptoms were positively associated with sleep disturbance.
Studies have reported that OSA impairs sleep quality and daytime functioning in bed partners. A study involving 46 bed partners of patients with OSA, with a median AHI of 41/h, reported that 66% reported sleep disturbance, defined as PSQI > 58. Virkkula et al. reported that 55% of bed partners reported snoring-induced sleep problems in patients with mild OSA (mean AHI: 13.7/h)7. Consistently, our findings indicated that 63.2% (86 of 136) of bed partners reported poor sleep quality (PSQI > 5); the mean PSQI score of the 136 bed partners was 7.8. However, the causal relationship between the nocturnal symptoms of patients with OSA and the sleep problems of bed partners has long been discussed. In an early study of 46 bed partners of patients with OSA, the subjective reasons for sleep disturbance included snoring (69%), apnea (54%), and restlessness (55%)8. However, the objective causes associated with sleep disturbance in the bed partners of patients with OSA have not yet been determined. In our study, PSG was used to determine the sleep parameters of patients with OSA associated with sleep disturbance of their bed partners. Our data revealed that the nocturnal symptoms from OSA, including the severity of AHI, frequency of snoring, and PLMS, did not affect bed partner–assessed sleep quality. Thus, the PSG-based objective assessments of patients with OSA could not explain bed partners’ subjective responses. A crossover study of 22 couples conducted by McArdle et al. indicated that the bed partners of patients with moderate to severe OSA did not experience a significant improvement in sleep quality, as determined by PSQI scores, after eliminating apnea–hypopnea and snoring in patients by using continuous positive airway pressure8. Therefore, we speculate that other OSA-related factors may cause sleep disturbance in bed partners; for example, the bed partner may be stressed about the patient’s health or be preoccupied with observing the patients’ breathing throughout the night after witnessing an apnea episode. More studies are warranted to identify the possible causes of sleep disturbance in the bed partners of patients with OSA.
OSA strains the personal relationships of patients, especially with their bed partners, and may lead to impaired mental functioning in the bed partners4. Few studies have examined the severity of depressive symptoms in the bed partners of patients with OSA. A prospective study of 45 patients with a mean AHI of 31.7/h revealed that 18% of their bed partners had symptoms of depression15. We found that 37.5% (51 of 136) of the bed partners had depressive symptoms (CES-D ≥ 16). Moreover, depressive tendency was independently associated with sleep disturbance and the level of depressive symptoms determined through CES-D scores had a positive correlation with the degree of sleep disturbance determined through PSQI scores in our study. Reporting a consistent finding, Raniti et al. discovered positive and moderate linear relationships (r = 0.58) between PSQI and CES-D scores in 889 participants24. A meta-analysis of prospective cohort studies involving 172 077 participants suggested that insomnia was significantly associated with an increased risk of depression25. A systematic review and meta-analysis indicated that treatment of insomnia eased depression26. These findings are consistent with ours; thus, we hypothesize that the depressive symptoms reported by the bed partners of patients with OSA could have been the result of their disturbed sleep and insomnia.
Mounting evidence suggests that sufficient sleep is crucial for maintaining good health and that inadequate sleep increases the risk of chronic diseases. A large cohort study involving 12 338 adults in Bangladesh observed that inadequate sleep was independently associated with chronic disease27. Our findings revealed that bed partners with sleep disturbance and depressive tendency were more likely to have chronic disease. Nevertheless, the mechanisms and associations among sleep disturbance, depressive tendency, and chronic disease remain unclear. Poor sleep quality and depression may directly or indirectly cause chronic disease. By contrast, chronic disease may either directly or indirectly lead to inadequate sleep or depressive symptoms. Further research is key to identifying any causal links among sleep disturbance, depression, and associated chronic diseases.
Our study had some limitations. First, the majority of the bed partners were female, and this may have independently influenced the higher incidence of both sleep disturbance and depressive symptoms. Second, we did not apply the PSG to the bed partners, and it was unclear whether the bed partners had OSA. Sleep disturbance may have been caused by bed partners’ own OSA, and this may have influenced the results. Third, we investigated sleep disturbance and depressive tendency in the bed partners of patients with OSA by using only one type of questionnaire, which may not have been sensitive to some of the feelings experienced by bed partners. Further research should incorporate more questionnaires for assessing sleep quality and depressive symptoms. Fourth, the self-reported data may have been affected by recall bias, especially considering that individuals with depression tend to remember and report more negative things. This bias may have led to an overestimation of the relative risk involved with various factors and thereby influenced the results.
In conclusion, sleep disturbance is often a shared experience for the bed partners of patients with OSA. However, the night symptoms from OSA, including the severity of AHI, snoring, and PLMS, may not affect partner-assessed sleep. Depression and chronic disease are associated with the sleep disturbance of bed partners, but their causal relationship is unknown. Additional studies are warranted to recognize the causes of poor sleep quality and the effects of OSA on bed partners.