Gender differences in the efficacy of brief interventions with a stepped care approach in general practice patients with alcohol-related disorders

Aim: To analyse gender differences in the efficacy of stepped care brief interventions for general practice patients with alcohol problems. Methods: Data are part of "Stepped Interventions for Problem Drinkers," in which 10,803 patients from 85 general practitioners were screened using alcohol related questionnaires; 408 patients were randomized (32% were female) to a control (booklet only) or two different intervention groups: stepped care (feedback, manual, and up to three counselling sessions depending on the success of the previous intervention) and fixed care (four sessions). Response rate for the 12 months follow-up was 91.7%. Results: Regression analysis revealed a significant effect size only in women (P = 0.039). After excluding alcohol dependents and binge drinkers, an effect size (R²) of 0.031 (P = 0.050) in women and an effect size (R²) of 0.069 (P = 0.057) in men was obtained. Among the patients in stepped care who, by the first assessment point, had reduced drinking to within safe-drinking limits, there was a tendency for females to have achieved this more often than males (40% vs. 24% P = 0.089). Conclusions: In a heterogeneous sample, the intervention was only effective for women. Women tended to profit more from the first, less intensive intervention than men. When analysis was limited to those reporting "at risk" average daily consumption and "alcohol abuse," the gender differences in efficacy appeared to be less, but the study was not sufficiently powered to affirm that.