Pediatric migraine is the most common cause of severe recurrent headache in children, and affects approximately 3% at age 5 and 14% at 15 years of age. The overall prevalence is approximately 11% (5 to 15 years of age). Pediatric migraine is responsible for school absenteeism, impaired school performance, and reduced social interaction with family and friends.^1,2 Although children with migraine experience disability similar to that of pediatric rheumatoid disease or cancer, migraine in children is often undiagnosed or inappropriately treated.^2,3 It is believed that a preventive migraine medication would help those children with frequent and/or severe migraines that interfere with daily activities.

To assess the efficacy and safety of Topamax in children with migraine, Dr. Paul Winner of the Palm Beach Headache Center in Florida, and colleagues, enrolled 162 children with migraine, diagnosed according to the International Headache Society criteria. The trial was randomized, double-blind, and placebo-controlled study and was conducted at 17 medical centers throughout the U.S. One hundred and twelve children (age 6-15 years) received Topamax and 50 received placebo. Topamax was started at a dose of 15 mg/day and over eight weeks was adjusted to 2-3 mg/kg/day (maximum dose was 200 mg/day). The target dose was maintained for 12 weeks.

Results
A total of 131 children (80.9%) completed the study. The average daily dose of Topamax during the maintenance period was 2.0 mg/kg/day. Topamax treatment was associated with a mean reduction of 2.6 migraine days/month compared to 2.0 for the placebo group. A significantly greater percentage of Topamax patients (32%) experienced a 75% or greater reduction in monthly migraine days compared with the placebo group(14%).

Discontinuations due to adverse events were 6.5% and 4.0% for the Topamax and placebo group, respectively. The adverse events experienced to a greater degree in the Topamax group compared with the placebo group were upper respiratory tract infection (19.4%), anorexia (13%), weight loss (10.2%), inflammation of the gastrointestinal tract (9.3%), a sensation of tingling, pricking, or numbness of the skin (8.3%), and sleepiness (8.3%). The majority of adverse events were mild to moderate in severity.

The researchers say that this pilot study suggests that Topamax may be an effective migraine preventive therapy in children, and that further studies are needed to support these initial conclusions.

References:
1. Abu-Arehef I, russell G. Prevalence of headache and migraine in schoolchildren. BMJ 1994;309:765-769.
2. Lee LH, Olness KN. Clinical and demographic characteristics of migraine in urban children. Headache 1997;37:269-276.
3. Powers SW, et al. Quality of life in childhood migraines: Clinical impact and comparison to other chronic illnesses. Pediatrics 2003;112:e1-e5.

Source:
Winner P, et al. Topiramate for migraine prevention in children: a reandomized, double-blind, placebo-controlled trial. Headache 2005;45:1304-1312.