Predictors of Physical Activity among Adults with Type 2 Diabetes Mellitus, Isfahan, 2015: Structural Equation Modeling Approach

Abstract

Background: The prevalence of Type 2 diabetes mellitus (T2DM) has been increasing globally in the recent decades. Physical activity (PA) helps preventing diabetes complications by keeping the blood sugar of T2DM patients within the normal range. The objective of this study was to explore underlying beliefs corresponding to PA in T2DM patients using health action process approach (HAPA). Methods: This cross-sectional study was conducted in Isfahan, 2015. A convenience sample of 203 participants with T2DM was collected. Participants completed HAPA inventory containing the following constructs: Risk perception, outcome expectation, task self-efficacy, intention, action and coping planning, coping self-efficacy, recovery self-efficacy, and PA questionnaire. Structural equation modeling was used for statistical analysis. Results: The common fit indices revealed that the HAPA had an acceptable fit to the observations (CMIN/df = 2.36 P < 0.001, root mean square error of approximation = 0.089, comparative fit index = 0.891, normal fit index = 0.902). Intention was associated with task self-efficacy (beta = 0.92, P < 0.001), whereas risk perception (beta = 0.16, P = 0.073) and outcome expectation (beta = 0.32, P < 0.081) did not predict intention to participate in PA behavior. PA was well predicted by planning (beta = 0.84, P < 0.01) while it was not significantly associated to coping self-efficacy (beta = 0.66, P = 0.73) and recovery self-efficacy (beta = 0.6, P = 0.69). Conclusions: HAPA could be used as a proper framework to identify the beliefs of the patients with T2DM and guide for effective theory-based interventions regarding PA.