Objective: To assess the short-term efficacy of zaleplon in older patients
with insomnia.
Design and Setting: Randomised, double-blind, placebo-controlled, Latin-squ
are design conducted in six sleep research centres.
Patients: 48 chronic insomnia patients, aged 60 to 80 years, without signif
icant psychiatric or medical illness.
Interventions: Placebo and zaleplon 2, 5 and 10mg.
Main Outcome Measures: Polysomnographic (PSG) and subjective sleep latency
and total sleep time.
Results: PSG studies showed that latency to persistent sleep was shortened
significantly (p < 0.015 or better) with all three zaleplon doses, as compa
red with placebo. Subjective sleep latency was reduced significantly with z
aleplon 5 or 10mg (p < 0.017 or better). Additionally, total sleep time was
significantly increased (p < 0.03 or better) compared with placebo at the
5 and 10mg doses based on PSG measures, but subjective assessments indicate
d that only the 10mg dose (p < 0.011) was superior to placebo on this varia
ble. Psychomotor tests conducted the morning after each polysomnogram showe
d no deficits with any dose of zaleplon as compared with placebo.
Conclusions: This study demonstrates short-term efficacy of zaleplon, parti
cularly at the 5 and 10mg doses, in older patients with insomnia.