Fiber Consumption in Constipated Older Adults; a Theory-Based Interventional Study

Aims: This study aimed to assess the effectiveness of an intervention on fiber consumption, self-efficacy, perceived benefit, and barriers among the elderly using the Trans-theoretical Model (TTM). Materials Methods: This quasi-experimental study was developed among constipated elderly people aged ≥60 in Karaj, Iran, between 2019 and 2021. Constipated participants were randomly assigned to the intervention (n=66) or the control (n=64) groups. Before and after four educational sessions, demographic information, participants’ stages of change for diet, self-efficacy, decisional balance, and daily amount of fiber consumption were evaluated. An analysis was performed to assess any differences in the stages of change (posttest vs. baseline). Findings: The perceived barriers and self-efficacy were statistically significant after intervention (p 0.001) in the intervention group compared to the control group (p 0.001). In both groups, perceived benefits changed statistically significantly (p 0.001). Pearson correlation also showed a significant correlation between stages of change and benefits, barriers, self-efficacy, and fiber consumption. The analysis of variance adjusting for covariates also indicated significant differences between intervention and control groups. Conclusion: The TTM is a useful model that can be applied to dietary behavior change, specifically fruit and vegetable consumption among elderly populations.