Validation of the Simplified Medication Adherence Questionnaire (SMAQ) in people living with HIV in a National Hospital in Mexico (Preprint)

Abstract

BACKGROUND Adherence to antiretroviral therapy is a critical component in achieving viral suppression in people living with HIV in addition to increasing overall quality of life. Several indirect methods have been used to measure adherence including the SMAQ. OBJECTIVE The objective of this study is to evaluate the reliability and validity of the Simplified Medication Adherence Questionnaire (SMAQ) in men living with HIV/AIDS attending a Mexican national hospital. METHODS A cross-sectional analytical design study was carried out in a Mexican National Hospital in Jalisco, including men >18 years old with at least three months in antiretroviral treatment, excluding those with cognitive difficulties to answer the survey. A minimum sample of 100 subjects was calculated. The analysis included descriptive tests, confirmatory factor analysis, reliability and validity assessment, correlation between adherence and viral load, and association between viral load and adherence. RESULTS The final analysis included a total of 260 patients with a mean age of 43 years and an average of 9 years on ART. The SMAQ showed sufficient structural validity (CFI=1.000, RMSEA=0.000, CI90% 0.000-0.085) with satisfactory factor loadings on most questions except item 2. The reliability of the scale is acceptable (α=0.702, ω=0.718). Adherence correlated with viral load significantly but not with recent TCD4 lymphocyte levels. Patients classified as adherent were three times more likely to be undetectable than those classified as non-adherent (MR=3.31, 95%CI [1.13-9.64], p=0.042). CONCLUSIONS The SMAQ represents an adequate tool to assess adherence in men in the Mexican context, this will contribute to the study and compression of adherence to establish future intervention programs. CLINICALTRIAL