Skepticism and pharmacophobia toward medication may negatively impact adherence to psychiatric medications: a comparison among outpatient samples recruited in Spain, Argentina, and Venezuela.

Background: Cultural differences in attitudes toward psychiatric medications influence medication adherence but transcultural studies are missing. The objective of this study was to investigate how attitudes and beliefs toward psychotropic medications influence treatment adherence in psychiatric outpatients in Spain, Argentina, and Venezuela.

Methods: A cross-sectional, cross-cultural psychopharmacology study was designed to assess psychiatric outpatients' attitudes toward their prescribed medication. Patients completed the Drug Attitude Inventory - 10 Item (DAI-10), the Beliefs about Medicines Questionnaire - Specific Scale (BMQ-Specific), the Sidorkiewicz adherence tool, and sociodemographic and clinical questionnaires. The study included 1,291 adult psychiatric outpatients using 2,308 psychotropic drugs from three Spanish-speaking countries, the Canary Islands (Spain) (N=588 patients), Argentina (N=508), and Venezuela (N=195).

Results: The univariate analyses showed different mean scores on the DAI-10 and the BMQ - Necessity and Concerns subscales but, on the other hand, the percentages of non-adherent and skeptical patients were relatively similar in three countries. Argentinian patients had a very low level of pharmacophobia. Multivariate analyses (logistic regression and chi-squared automatic interaction detector segmentation) showed that pharmacophobia in general and skepticism about specific medications (high concern about adverse reactions and low belief in their necessity) were associated with non-adherence. Pharmacophobia was the major factor associated with non-adherence (Spain and Venezuela) but when pharmacophobia was rare (Argentina), skepticism was the most important variable associated with non-adherence.

Conclusion: Psychiatric patients' attitudes and beliefs about their psychiatric treatment varied in these three Spanish-speaking countries, but pharmacophobia and skepticism appeared to play a consistent role in lack of adherence.