Modafinil reduces excessive somnolence and enhances mood in patients with myotonic dystrophy.
OBJECTIVE
To evaluate the potential of modafinil in reducing excessive daytime somnolence (EDS) and enhancing indexes of quality of life and mood in patients with myotonic dystrophy (DM).


METHODS
Forty patients with DM were randomized to receive modafinil and placebo for 14 days each, using a double-blind, cross-over design. Before and after each trial, subjects completed handgrip strength testing, spirometry, and quality-of-life measures (RAND). On days 7 and 14, each subject completed the Epworth Sleepiness Scale (ESS), the Stanford Sleepiness Scale (SSS), and the Profile of Mood States (POMS).


RESULTS
ESS scores were lower while taking modafinil (mean 248 mm; 95% confidence limit 220 to 276 mm) as compared with placebo (309 mm; 281 to 336 mm) (p < 0.001). Mean SSS scores were also lower during the modafinil trial (3.05; 2.77 to 3.33) than during the placebo trial (3.45; 3.18 to 3.71) (p < 0.05). The POMS indicated that modafinil decreased fatigue-inertia (p < 0.001) and increased vigor-activity and tension-anxiety (p < 0.001) indexes. The total mood disturbance score was also decreased during the modafinil trial as compared with placebo (p < 0.05). The RAND quality-of-life measures of energy (p < 0.001) and health change (p < 0.05) were both significantly enhanced during the modafinil treatment phase. No changes in maximal grip strength or forced expired volume in 1 second were detected over the course of the study. Headache was the most frequently reported adverse event. Four patients withdrew from the study, three because of side effects (two during modafinil ingestion and one during placebo ingestion).


CONCLUSIONS
Modafinil reduces somnolence and improves mood in patients with DM.
MacDonald
J R
JR
Department of Medicine, McMaster University Medical Center, Hamilton, and Draxis Health Inc., Mississauga, Ontario, Canada.
Hill
J D
JD
Tarnopolsky
M A
MA
D000203:Activities of Daily Living; D000293:Adolescent; D000328:Adult; D000339:Affect / Q000187:drug effects*; D001559:Benzhydryl Compounds / Q000009:adverse effects / Q000627:therapeutic use*; D000697:Central Nervous System Stimulants / Q000009:adverse effects / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D005541:Forced Expiratory Volume; D018737:Hand Strength; D006801:Humans; D008297:Male; D008875:Middle Aged; D000077408:Modafinil; D009223:Myotonic Dystrophy / Q000188:drug therapy* / Q000523:psychology*; D009460:Neurologic Examination; D011446:Prospective Studies; D011788:Quality of Life; D012894:Sleep Stages / Q000187:drug effects*
D001559:Benzhydryl Compounds; D000697:Central Nervous System Stimulants; D000077408:Modafinil