Effect of necessity-concern framework and polypharmacy on treatment adherence in psychiatric patients. Comparing an Argentinian with a Spanish sample.

OBJECTIVE: We aimed to replicate a prior Spanish study of medication adherence where logistic regression models provided highly significant odds ratios (ORs) for three continuous scores: necessity, concern and the necessity-concern differential, and a dichotomous variable: skeptical attitude. Adherence ORs in the necessity-concern framework were very strong in patients taking five or six medications. METHODS: The sample comprised consecutive adult psychiatric outpatients in Mendoza, Argentina. The necessity-concerns framework was assessed using a subscale of the Beliefs about Medicines Questionnaire. Adherence (yes/no) to prescribed psychiatric medications was assessed by the Sidorkiewicz adherence tool. RESULTS: When compared with the Spanish sample, the Argentinian group (508 patients with 875 medications) was characterized by: (1) significantly stronger adherence ORs with the necessity-concern framework, (2) significantly lower number of medications per patient and percentage of patients with marked psychiatric polypharmacy (≥4 medications), (3) though a higher number of medications still was significantly associated with poor adherence. CONCLUSIONS: The Argentinian sample replicated the previous finding that patient beliefs regarding necessity and concern were associated with poor adherence to prescribed medications. Polypharmacy had an additive role decreasing adherence in both samples. In both samples, when prescribed ≥4 psychiatric medications, patients reported adherence to only two-third of the medications.

Ethnopsychopharmacology study of patients' beliefs regarding concerns about and necessity of taking psychiatric medications.

OBJECTIVE: The aim of this study was to examine whether or not cultural differences influence beliefs about the necessity of taking prescribed psychiatric drugs and concern about their adverse effects in psychiatric outpatients in Spain, Argentina, and Venezuela. METHODS: This cross-sectional study included 1,372 adult psychiatric outpatients using 2,438 psychotropic drugs and was designed to assess outpatients' beliefs about their prescribed medication. Patients completed sociodemographic, clinical questionnaires, and the Beliefs about Medicines Questionnaire Specific Scale and registered scores ranging from 1 to 5 on each of two subscales: concern and necessity. A "necessity-concern differential" was obtained by calculating the difference (range -4 to +4). RESULTS: The global score, including all drugs in the total sample, had a mean necessity score of 3.50 ± 0.95, a mean concern score of 2.97 ± 0.99, and a mean differential score of 0.54 ± 1.42. The concern and necessity mean scores varied significantly across these three culturally Hispanic countries, probably across drug classes, and were associated with treatment duration. On the other hand, age and education played a very limited role. CONCLUSIONS: Understanding the diverse effects of culture and society on these attitudes is highly relevant for the development of responsive mental health services in multicultural societies.