Low body mass index is associated with an increased risk of neuropsychiatric adverse events and concentration impairment in women on mefloquine

textabstractAims: We performed a prospective cohort study to gain more insight into risk factors for neuropsychiatric effects of mefloquine among tourists travelling to tropical areas. Methods: We enrolled all patients who consulted the Travel Clinic of the Havenziekenhuis & Institute for Tropical Diseases Rotterdam for mefloquine prophylaxis during the period between 1 May 1999 and 7 March 2000. Each patient was followed from baseline (prior to starting mefloquine) up to 3 weeks after starting weekly intake of 250 mg mefloquine. We compared the intraindividual change in scores between baseline and follow-up visit on the Dutch shortened Profile of Mood States, and on the Continuous Performance Test (CPT) which measures sustained attention. Results: The final cohort consisted of 151 subjects with a mean age of 38 years. In this population, a significant impairment of mood state was observed in those with a body mass index (BMI) ≤20 kg m -2. Stratification for gender showed that the total mood disturbance in females in the lowest BMI category significantly increased by 8.42 points [95% confidence interval (CI) 3.33, 13.50], whereas BMI did not affect the risk in males. Stratification for history of use of mefloquine showed that the risks were highest in first-time users. Analyses of the CPT showed that reaction time in women with a BMI ≤20 kg m -2 increased significantly by 22.5 ms (95% CI 7.80, 37.20), whereas reaction time in men showed a slight and nonsignificant decrease. Conclusion: Risk factors for mefloquine-associated neuropsychiatric adverse events and concentration impairment are female gender, low BMI, and first-time use. The frequency of neuropsychiatric effects is highest in women with a BMI ≤20 kg m -2