Gabapentin in the treatment of tremor

Patients and methods. We evaluated the efficacy of gabapentin added to basal tremor treatment by means of a 16-month non-randomized open study conducted at our Unit on treated and monitored patients. Efficacy was evaluated by means of the following scales: Tremor Scale (TS), Global Disability Examiner Scale (GDE) and Global Disability Patient Scale (GDP). For the GDE and GDP scales we constructed a dichotomic result evaluation variable (improvement vs. non-improvement) and adjusted a logistic regression model (independent variables: age, gender, tremor duration and number of antitremor drugs associated with gabapentin). Two multiregression models were adjusted for the TS (12-month score result variable). Model 1: TS(items 1-14) and model 2: TS(items 15-21). Independent variables: age, gender, tremor duration, initial test score and number of antitremor drugs associated with gabapentin. We studied 63 patients aged 59.4 years (SD, 16 years): 34 essential tremor, 16 Parkinson's disease tremor, 10 multiple sclerosis tremor, 4 writing tremor and 3 orthostatic tremor. Results. At 12 months gabapentin improved the clinical results. The largest decrease (absolute terms) was observed in multiple sclerosis tremor, and in percentage terms the largest decrease was in orthostatic tremor. Logistic regression showed that masculine gender and a shorter tremor duration predicted a better result. Multiregression showed association between end and basal score, on the one hand, and a better result in males and shorter tremor duration, on the other.