Motivational Interviewing in the Management of Type 2 Diabetes Mellitus and Arterial Hypertension in Primary Health Care: An RCT

Abstract

Motivational interviewing is an effective style of collaborative communication for the promotion of lifestyle changes in the management of Type 2 diabetes and arterial hypertension. This study evaluates the effectiveness of motivational interviewing in the management of these conditions in primary health care. This study is a double-blind parallel-group RCT performed between June 2018 and July 2019. The RCT was conducted in Porto Alegre, Rio Grande do Sul, Brazil, and included individuals with Type 2 diabetes and arterial hypertension. The participants were randomized to the test/motivational interviewing and usual care groups. The test/motivational interviewing group received the nursing consultation intervention on the basis of motivational interviewing conducted by professionals with 20 hours of training, and the usual-care group received conventional nursing consultation. The main outcome measure was the mean difference in HbA1c. The secondary outcome measures were the mean differences in blood pressure and adherence levels. After a mean follow-up of 6 months, 174 participants completed the study (usual-care group=80; test/motivational interviewing group=94). There were statistically significant differences between the groups, with improvement in the test/motivational interviewing group for systolic blood pressure (p<0.01), diastolic blood pressure (p<0.01), and total adherence score as measured by the Martín-Bayarre-Grade questionnaire (p=0.01) and its operational dimensions of treatment adherence and personal involvement (p=0.03, p=0.03). The test/motivational interviewing group showed significantly reduced HbA1c levels (0.4%) at the end of the study (p<0.01). In the context of primary health care, the nursing consultation based on motivational interviewing was shown to be a more effective care strategy than usual care for improving blood pressure levels and adherence levels in individuals with Type 2 diabetes and arterial hypertension. Moreover, motivational interviewing was demonstrated to be useful in reducing HbA1c levels in diabetes management. This study is registered at www.clinicaltrials.gov NCT03729323.