An evaluative study of the short-term effects of once-daily, sustained-release theophylline on sleep in nocturnal asthmatics.
OBJECTIVE
To examine the effects of once-daily, sustained-release theophylline on sleep patterns in nocturnal asthmatics.


METHODS
Double-blind, randomised, cross-over, placebocontrolled trial over 22 days. Seven-day period to establish therapeutic levels of theophylline (11.8 +/- 3 mg/l); 8-day cross-over period of 4 days' placebo or theophylline; 7-day baseline period. Electrophysiological sleep patterns, overnight bronchoconstriction and arterial O2 saturation monitored on nights 7, 11 and 15.


METHODS
Sleep Laboratory, Medical School, University of the Witwatersrand.


METHODS
Twelve volunteers who met the criteria for asthma, had previously used theophylline, were clinically stable and had a history of nocturnal awakenings caused by asthma were enrolled.


METHODS
Sleep-onset latency (SOL), within-sleep wakefulness (WSW), rapid eye movement sleep (REM), slow-wave sleep (SWS), peak expiratory flow rate (PEFR) and arterial oxygen saturation.


RESULTS
SOL increased on theophylline--12 minutes (range 7-9 minutes) compared with placebo--6 minutes (range 3-11 minutes); WSW increased from 33 minutes (range 17-66 minutes) on placebo to 72 minutes (range 35-150 minutes) on theophylline. REM sleep was unaltered. SWS decreased in 10-12 patients, but this difference was not significant. Early morning PEFR was significantly better on theophylline in all study limbs.


CONCLUSIONS
Our findings show that while once-daily, sustained-release theophylline improves bronchodilation in nocturnal asthmatics, it increases nocturnal wakefulness and decreases sleep efficiency during short-term treatment. This may, however, not be a long-term effect.
Richardt
D
D
Department of Experimental and Clinical Pharmacology, University of the Witwatersrand, Johannesburg.
Driver
H S
HS
D000328:Adult; D000704:Analysis of Variance; D001249:Asthma / Q000097:blood / Q000188:drug therapy* / Q000503:physiopathology; D001993:Bronchodilator Agents / Q000008:administration & dosage* / Q000097:blood / Q000494:pharmacology; D002940:Circadian Rhythm; D018592:Cross-Over Studies; D003692:Delayed-Action Preparations; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008168:Lung / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010919:Placebos; D012890:Sleep / Q000187:drug effects*; D013806:Theophylline / Q000008:administration & dosage* / Q000097:blood / Q000494:pharmacology
D001993:Bronchodilator Agents; D003692:Delayed-Action Preparations; D010919:Placebos; D013806:Theophylline