Telehealth Intervention to Reduce Sedentary Behavior in Older Adults With Type 2 Diabetes: Development and Feasibility Study

Background: Sedentary behavior (SB) is a modifiable risk factor for complications in older adults with type 2 diabetes mellitus (T2DM). Despite widespread adoption of digital health platforms, theory-driven telehealth interventions specifically targeting SB reduction remain limited, particularly those incorporating cultural adaptation and behavioral change frameworks. Objective: This study aims to develop and evaluate the feasibility of a theory-based personalized telehealth intervention to reduce SB in older adults with T2DM in China. Methods: The intervention was developed over 14 months (January 2022-February 2023) following the intervention mapping and Behavior Change Wheel frameworks. A panel of 19 multidisciplinary experts (90.5% response rate) refined the program through a systematic iterative process. Subsequently, a 7-week quasi-experimental study (pre-post self-controlled design) was conducted to assess feasibility. We recruited 30 community-dwelling older adults with T2DM via WeChat-based convenience sampling. The primary outcome was SB measured by the Measure of Older Adults' Sedentary Time for Type 2 Diabetes Mellitus questionnaire. Secondary outcomes included cardiovascular risk (blood pressure), glycemic control (fasting blood glucose), Diabetes-Specific Quality of Life, social isolation, BMI, and fall incidence. Pre-post changes from baseline to 7 weeks were statistically evaluated to assess the intervention's feasibility and preliminary impact. Results: The intervention comprises 5 components: an eHealth education manual, a motion graphics library, an SMS text messaging library, a WeChat Q&A group, and a material incentive package. These components address "knowledge," "social support," and "intention" determinants through "education," "enablement," and "incentivisation" functions, respectively. All components used the "service provision" policy and various behavior change techniques. Preliminary feasibility testing (n=31) showed reduced sedentary time by 1.12 hours/day (P