Insomnia prevalent in sleep apnea patients
MedWire News: Insomnia is common among patients with obstructive sleep apnea (OSA) and is associated with reduced quality of life and increased daytime sleepiness, research shows.
"Complaints of insomnia are frequent among OSA patients and in recent years there has been a growing interest in the coexistence of these disorders," explain Bryndís Benediktsdóttir (University of Iceland, Reykjavik) and team.
"However, there has been a lack of studies directly comparing the prevalence of insomnia and its subtypes between untreated OSA patients and controls from the general population," they add.
To address this, the researchers studied 824 untreated OSA patients (81% men), aged a mean of 54 years, and 762 randomly selected controls (53% men), aged a mean of 56 years, from the general population in Iceland.
All of the participants were assessed for insomnia (difficulty initiating sleep [DIS] and difficulty maintaining sleep [DMS]) using the Basic Nordic Sleep Questionnaire, for daytime sleepiness using the Epworth Sleepiness Scale (ESS), and for quality of life using the 12-item Short Form questionnaire (SF-12).
The researchers found that DIS was more common in men and women with OSA compared with those in the control group, at 12.6% versus 9.4%, and 27.3% versus 18.1%, respectively, although the difference was only significant among women.
DMS was also more common among men and women with OSA compared with controls, at 51.6% versus 30.7% and 62.4% versus 31.0%, respectively, with significant between-group differences observed for both men and women.
Furthermore, DIS combined with DMS was significantly more common in women with OSA compared with women in the control group, at 19.7% versus 10.3%, with no significant differences among men with or without OSA.
OSA patients with DMS experienced more daytime sleepiness than those without DMS, with ESS scores of 12.2 versus 10.9, while there were no significant differences in ESS scores between OSA patients with and without DIS.
In patients with OSA, those with DIS had significantly lower physical and mental quality of life than those without, at SF-12 scores of 36.3 and 43.2 versus 41.0 and 49.2, respectively, as did OSA patients with DMS compared with those without, at 38.9 and 47.6 versus 42.2 and 49.4, respectively.
However, the researchers note that DIS and DMS were not associated with OSA severity in the patient group.
Benediktsdóttir and team conclude in the Journal of Sleep Research: "Insomnia is common among OSA patients and has a negative influence on quality of life and sleepiness in this patient group. It is relevant to screen for insomnia among OSA patients and treat both conditions when they co-occur."
They add: "Providers should consider treating both conditions together when they co-occur in order to maximize clinical outcomes. This may lead to both direct improvement in symptoms by reducing the severity of insomnia, and indirectly by influencing adherence to continuous positive airway pressure treatment."
By Mark Cowen