Efetividade de intervenção educativa em alimentação e nutrição para usuários da atenção primária à saúde com diabetes mellitus tipo 2: ensaio clínico randomizado

Abstract

This study focused on evaluating the effectiveness of an educational intervention on diet and nutrition regarding knowledge about diabetes, coping with the disease, and dietary choices and practices among adult and elderly patients with type 2 diabetes mellitus receiving primary health care in Juiz de Fora, Minas Gerais. This was a randomized controlled trial conducted at two Basic Health Units, using a non-probabilistic convenience and adherence sample, with participants allocated to the experimental (n = 22) and control (n = 14) groups based on clusters from the participating units. The interventions lasted three months per subgroup, with biweekly meetings. In addition to in-person nutritional counseling, the experimental group received validated printed educational materials (Content Validity Index = 0.99) and digital audio content. An interview form was used to collect data on demographic characteristics and health service utilization, along with the DiAbeTes Education Questionnaire, the Problem Areas in Diabetes Scale, the Food Choice Questionnaire, the Dietary Practices Assessment Scale, and a satisfaction survey. Categorical data were presented as absolute and relative frequencies, while numerical data were expressed as mean, standard deviation, median, and 25 and 75 percentiles. To compare the groups, we used the chi-square test or Fisher’s exact test and McNemar’s test for nominal categorical variables, and the Mann-Whitney and Wilcoxon tests for ordinal variables. Mixed-effects analysis of variance allowed for multiple pairwise comparisons with Bonferroni correction. The respective effect sizes were calculated. Analyses were conducted using R software version 4.3.3; a significance level () of 5% was used. During the follow-up period, three participants were lost to follow-up in the experimental group (n = 19) and one in the control group (n = 13). There were no significant differences in sociodemographic variables between the groups; the participants were predominantly women, self-identified as mixed-race, married, with incomplete elementary school education, and in socioeconomic class E. Most had been diagnosed with diabetes within the past four years; one-quarter visited Basic Health Units one to three times a month, primarily for medical consultations and to pick up medications. The DiAbeTes Education Questionnaire score showed a group effect (Experimental Group × Control Group) (p = 0.010) and a time effect (baseline × follow-up) (p < 0.001), but no interaction between these (p = 0.206). The Problem Areas in Diabetes Scale scores showed no effect of group (p = 0.743), time (p = 0.078), or interaction between these (p = 0.535). The Assessment of Eating Practices detected a main effect of time (p < 0.001), but not of group (p = 0.526) or an interaction between the two (p = 0.406). On the Food Choice Questionnaire, both groups showed increased scores on the “natural content” and “health” factors. For 100% of participants, the “spoken information” was “very useful.” For 94.7% of the experimental group, the “printed material” was “very useful,” and 78.9% considered the “audio recordings” “very useful.” The educational intervention, although not statistically significant, demonstrated practical relevance for promoting improved knowledge about diabetes and proper, healthy eating.