Effectiveness of dietary intervention among people with diabetes mellitus: A quasi-experimental study

BACKGROUND: This study was aimed to evaluate the impact of intervention based on the behaviour change theory on dietary practices among patients with T2DM living in rural areas. METHODS: A quasi-experimental study was carried out in a rural area of district Fatehgarh Sahib of Punjab, North India. A total of 700 people with T2DM was screened for the eligibility from the randomly selected rural health centeres. The baseline survey included a total of 584 eligible T2DM patients (283 in the intervention and 291 in the control arms), whereas the endline survey included a total of 479 participants (242 in the intervention and 237 in the control arms). A prevalidated and structured food frequency questionnaire at baseline and at the end of 6 months of follow-up. The outcomes of study were mean changes in the total calorie intake from carbohydrate and fat, salt intake, fiber intake and biochemical measurements namely fasting plasma blood glucose, and proportion of population having HbA1c ≤ 7%. Difference in difference analysis (DiD) using Generalized Estimating Equation (GEE) model was applied to adjust for confounders. Statistical significance was considered p < 0.05. RESULTS: DiD suggested a significant decrease in mean: total calorie intake (-857 kcal/day; 95% CI -1115 - -599, p < 0.001), calorie intake from carbohydrates (-569 kcal/day; 95% CI -729 - -410, p < 0.001), calories intake from fat (-329 kcal/day; 95% CI -438 - -220, p < 0.001) and dietary salt intake (-5 gm/day; 95% CI -7 - -3, p < 0.001). There was also a significant increase in the mean dietary fiber intake (4 gm/day; 95% CI 0.82 - 7, p = 0.01), a decrease in the mean FPBG (-42 mg/dl; 95%CI: -55 - -29, p < 0.001) and a significant increase in proportion of participants having HbA1c within range (≤7%), (8%; 95%CI:1% - 14%, p = 0.01). CONCLUSIONS: Study suggested dietary interventions based on the behaviour change theory helped to achieve optimal dietary habits and glycemic stability among patients with T2DM living in rural areas. KEY MESSAGES: • This study emphasised the advantage of behaviour change interventions implementation based on behaviour change theories among patients with T2DM. • T2DM patients can be encouraged to follow healthy dietary habits by using tailored instructions.