Aims: COMISA (comorbid insomnia and obstructive sleep apnea) is associated with daytime functioning and cognitive impairments. Some sleep-promoting medications may exacerbate daytime impairment. This post hoc analysis assessed the impact of lemborexant (LEM), a dual orexin-receptor antagonist approved to treat insomnia in adults, on morning sleepiness/alertness in participants with COMISA.
Methods: Of the overall population (n=1006), 410 (40.8%) adults (≥55 years of age) with comorbid insomnia disorder (Diagnostic and Statistical Manual, 5th edition; Insomnia Severity Index score ≥13) and mild obstructive sleep apnea (apnea-hypopnea-index, 5 to ≤15 events/h) from Study E2006-G000-304 (NCT02783729), a 1-month, randomized, placebo- and active-controlled study, were analyzed. Participants received placebo (PBO), LEM 5mg (LEM5), LEM 10mg (LEM10), or zolpidem tartrate 6.25mg (not reported). A daily sleep diary assessed morning sleepiness/alertness rated from 1 (extremely sleepy) to 9 (extremely alert). The percentage of participants shifting from baseline mild/moderate sleepiness (≤3) towards greater alertness (4, 5, or >5) during the first and last 7 mornings of the study was analyzed.
Results: At baseline, 17/75 (22.7%), 36/112 (32.1%), and 28/104 (26.9%) participants with COMISA receiving PBO, LEM5, or LEM10, respectively, reported mild/moderate sleepiness. Of these participants, across the first and last 7 mornings, a greater percentage shifted from mild/moderate sleepiness towards alertness with LEM5 (66.7%, 82.9%) and LEM10 (64.3%, 75.0%) versus PBO (47.1%, 64.7%), respectively.
Conclusions: A greater percentage of participants with COMISA experienced improvements in morning sleepiness across the treatment period with LEM versus PBO. Consistent with previous findings, LEM does not affect tasks requiring morning alertness.