Association between age and comorbid insomnia and sleep apnea

Purpose: To investigate the age-related prevalence of comorbid insomnia and sleep apnea (COMISA). Methods: A single-night polysomnography with video monitoring was conducted on 2176 Chinese adults (ages 18-102) to screen for obstructive sleep apnea (OSA). Insomnia was defined as difficulty initiating or maintaining sleep, or early morning awakening at least three times per week for more than three months, accompanied by daytime symptoms such as irritability, fatigue, or anxiety. Results: Of the participants, 981 met the criteria for COMISA, defined by an apnea-hypopnea index (AHI) of >= 5 and the presence of insomnia. Compared to patients with OSA only (n = 433), COMISA patients were more often female (48 % vs. 24 %), had longer sleep onset latency (5.8 min), shorter total sleep time (14.0 min), lower AHI (14.4 points), and higher mean peripheral oxygen saturation (0.6 %; all p < 0.05). The prevalence of COMISA versus OSA only was 51.9 % vs. 48.1 % in participants under 50 years, compared to 78.1 % vs. 21.9 % in those aged 70 or older. Logistic regression analysis adjusted for sex showed a 3 % increase in the odds of COMISA (95 % CI: 1.02-1.04) with each additional year of age. Conclusions: Our findings reveal a significant association between increasing age and the development of COMISA, underscoring the need for heightened clinical awareness of this condition in elderly patients.