Effects of Adding a Registered Dietitian to Rural Community Healthy Behavior Support Services for Management of Type 2 Diabetes

Summary abstract: Rural communities experience health care shortages of diabetes services provided by a registered dietitian nutritionist (RDN). This pilot study tested the feasibility of using rural community health screenings to recruit adults with Type 2 Diabetes (T2D) and provide Medical Nutrition Therapy (MNT), testing its impact on health, diet, and physical activity. Recruitment, retention, and adherence rates measured feasibility. Health markers [body mass index (BMI), non-fasted blood glucose and lipids, blood pressure, waist circumference] were collected at an initial and follow up (6-9 months) screening. Diet (24-hr) and physical activity (7-day) recalls were collected at the MNT visits (initial, 1 month, 3 month). Paired t-tests and linear mixed models assessed mean differences between timepoints.

Introduction: In the U.S., approximately 38.1 million adults aged 18 years or older have diabetes which is a prevalence rate of 14.7% based on 2021 estimates. Of these cases, 90% to 95% are type 2 diabetes (T2D). The estimated prevalence of diabetes in Indiana is 12.1% based on 2021 estimates.

Individuals with T2D are highly susceptible to major complications such as heart disease, stroke, renal failure, blindness, and amputations. The total estimated cost attributable to diabetes and its complications in the U.S. in 2022 is $412.9 billion. There are significant geographic disparities in diabetes prevalence between rural and urban areas. Prevalence of diabetes has been reported from 9% to 17% higher in rural areas than in urban areas. Diabetes has been identified as one of the top 10 Healthy People 2030 priorities for the rural United States. Rural communities experience health care shortages of not only primary care doctors for diabetes but also services provided by a registered dietitian nutritionist (RDN) such as medical nutrition therapy (MNT) and diabetes education. While RDs have been incorporated in team-based care in primary care clinics, team-based care models and support services (including a RDN) in rural communities are not typically present. This pilot study focused on Indiana rural communities experiencing health care shortages of diabetes service. The study's objectives were to test: (1) the feasibility of using rural community health screening events to recruit participants with T2D, (2) the feasibility of implementing MNT virtually by a RDN for 3 months, (3) the impact of the MNT on health markers of diabetes management, dietary intake and physical activity.

Methods:

Study population: Participants in SIHHH with T2D living in Southern Indiana counties (Crawford, Daviess, Dubois, Greene, Jackson, Lawrence, Martin, Orange, and Washington) were referred by nurses (RN) to the RDN as part of healthy behavior support services. The goal was to recruit 20 adults ≥ 18 years old with body mass index (BMI) ≥ 25 kg/m2 and a T2D diagnosis.

The enrollment of 20 participants was meant to allow the researchers to pilot test the feasibility of MNT delivered virtually by a RDN for 3 months, by assessing metrics regarding recruitment, enrollment and retention as well as the impact on changes in BMI and hemoglobin A1c (HbA1c) from the initial health screening to the follow up health screening. This data was intended to evaluate delivery of the intervention, as well as to obtain data on changes in biometrics for power calculations for a future randomized controlled trial.

Outcome measures: Feasibility outcomes included the number of health events and health screens, recruitment, retention, and adherence to MNT. Behavior outcomes included dietary intake and physical activity. Health outcomes included BMI, HbA1c, non-fasting blood glucose and lipids (total, HDL, and LDL cholesterol, triglycerides), blood pressure, and waist circumference.

Intervention: The SIHHH program provided RN led health screenings at public health centers/clinics, within health ministry centers/offices, mobile units, and health fairs. Health screenings included collection of demographics, weight, height, blood glucose, blood lipids, blood pressure, and waist circumference. HbA1c was calculated using blood glucose [Average HbA1c = (46.7 + non fasting glucose)/28.7]. RNs identified participants who met eligibility criteria of the pilot study and provided information about the MNT service. Individuals who expressed interest signed a consent form to receive the MNT, agreed to researchers' access to their electronic records as part of SIHHH, and agreed to provide information on their diet and physical activity habits. Participants were provided a packet of resources including Healthy Eating and Being Active from the Association of Diabetes Care \& Education Specialists, Meal Planning and Carb Counting from Novo Care of Novo Nordisk, and Healthy and Balanced Eating with MyPlate from United States Department of Agriculture. Participants were also provided a set of food measuring utensils and a My Plate food plate to assist with portion size. As part of the SIHHH Program, follow up health screenings occurred at 6-8 months post the initial screening. This data was evaluated to understand if there is any sustained impact of the MNT.

The MNT intervention was delivered virtually for three months by the RDN, who was also a Certified Diabetes Educator (CDE). During the initial MNT visit, the RDN used motivational interviewing techniques to identify the participant's interests and motivation for diabetes management. Participants set one goal on nutrition/healthy eating and one goal on physical activity. Based on the goals, the RDN provided diabetes education on blood glucose targets, use of blood glucose monitor, menu planning, or carbohydrate counting; eventually all of these topics were included in the subsequent MNT visits. To obtain data on dietary intake and physical activity, respectively, the RDN administered a 24-hr dietary recall and a 7-day physical activity recall (International Physical Activity). The 24-hour dietary recall included details about food/beverage intake, food preparation, and meal timing. The 7-day physical activity recall included details on types and intensity of activities as hours per day and number of days with at least 10 minutes of the activity. The RDN also administered these recalls during the 1- and 3-month visits encouraging health behavior changes to improve blood glucose levels. The RDN continued to address meal planning, carbohydrate counting, portion size, macronutrients, eating out, and physical activity during the 1- and 3-month visits. The RDN continued to use motivational interviewing techniques to assess progress and determine areas for improvement. The MNT intervention ended after the 3-month visit. Repeated measures of the biometric data were collected at the health screening which occurred at 6-8 months post the initial screening.

Data Analysis: Feasibility outcomes including the number of health events and screenings, recruitment, and retention were recorded. Adherence to the intervention was measured by recording attendance at the MNT visits. Dietary intake and physical activity data collected at the initial, 1- and 3-month MNT visits were analyzed using linear mixed models to evaluate changes overtime. The dietary data was assessed using the Nutrition Data System for Research (NDSR, University of Minnesota) for calories, macronutrients and micronutrients and change from initial visit to the 1- and 3- month MNT visits were analyzed. Change from initial visit to the 1- and 3-month MNT visits for hours per day and days of at least 10 minutes of physical activity were analyzed. Health outcomes including BMI, HbA1c, blood glucose, lipids, and blood pressure obtained from the SIHHH initial health screening (prior to MNT) and at the SIHHH follow up health screening (6-8 months) were used to determine changes overtime. Statistical differences from the initial screening to the follow up screening were determined using paired t-tests.