A Psychological-behavioral Intervention to Increase Activity in Type 2 Diabetes

The investigators will compare a combined positive psychology and motivational interviewing (PP-MI) intervention that is adapted for patients with T2D to a diabetes education intervention (control) in a randomized controlled trial. The investigators will enroll 70 participants, who will be randomized to either a 16-week PP-MI health behavior intervention or an 16-week diabetes education intervention.

In this project, the investigators plan to do the following:

• Examine the feasibility and acceptability of a 16-week, telephone-delivered health behavior intervention utilizing PP exercises and MI with systematic goal-setting.
• Determine whether the PP-MI intervention leads to greater increases in physical activity than the education intervention in T2D patients.
• Explore the impact of the PP-MI intervention on other psychological, behavioral, and medical outcomes, compared to the education intervention.

Participants will undergo an initial screening visit during which they will meet with study staff in person. At this visit, study eligibility will be confirmed, and eligible and willing participants will be enrolled. Following enrollment, participants will complete self-report measures, and vital signs and A1c will be measured. They then will take home and wear an accelerometer for one week, to measure baseline physical activity.

Baseline information about enrolled participants will be obtained from the participants, care providers, and the electronic medical record as required for characterization of the population. This information will include data regarding medical history (type 2 diabetes mellitus), current medical variables (conditions affecting physical activity), medications, and sociodemographic data (age, gender, race/ethnicity, living alone).

Participants will undergo a second in-person visit once adequate baseline physical activity data has been obtained. In this visit, accelerometer data will be reviewed to ensure that adequate baseline activity was captured. If so, participants will be randomized to either the PP-MI or diabetes education condition, then begin the study intervention. During this second in-person visit, participants will receive either a PP-MI or diabetes education treatment manual, depending on randomization.

For the PP-MI intervention:

For each session, a PP exercise will be described in the manual, with instructions and space to write about the exercise and its effects. Next, an MI section will outline specific MI-based topics (e.g., pros/cons, managing slips) and facilitate physical activity goal-setting. At subsequent sessions, participants will review the prior week's PP exercise and learn about a new exercise, then will review the prior week's physical activity goal and set a new one.

For the diabetes education intervention:

Each week, participants will learn about a different health behavior topic related to diabetes health. This includes information about diabetes self-monitoring, medication adherence, having a heart-healthy diet, and being physically active.

Participants will complete the remaining sessions by phone approximately weekly over the next 16 weeks. Phone sessions will last approximately 30 minutes, with PP-MI and physical activity assignments completed between phone sessions. PP and MI will be delivered step-wise within sessions (rather than intertwined) based on our experience, participant feedback, and pilot work. If a week is missed, the session will not be skipped, but rather the intervention will be completed sequentially (with participants who miss weeks then missing the final sessions), with the exception of the final visit, which skips to Planning for the Future in all cases.

Participants will undergo an in-person follow-up assessment at 16 weeks. At this session, participants will repeat self-report assessments that were administered at baseline. Vital signs and a blood sample will again be collected at this in-person visit. Prior to this assessment, participants will wear an accelerometer for 7 days to measure physical activity. Participants will also undergo a phone follow-up assessment at 24 weeks. During this session over the phone, participants will repeat self-report assessments that were administered at baseline. Finally, prior to this follow-up, participants will wear another accelerometer for 7 days to measure physical activity.

Inclusion criteria

• T2D. Eligible patients will meet American Diabetes Association (ADA) criteria for T2D (e.g., HbA1c [A1C] ≥6.5%, fasting glucose ≥126 mg/d), with diagnosis confirmed by their diabetes clinician and/or medical record review.
• Low physical activity. Low physical activity will be defined as ≤150 minutes/week of MVPA (corresponding to ADA recommendations for moderate or greater intensity aerobic physical activity). Physical activity will be measured using a brief questionnaire adapted from the International Physical Activity Questionnaire (IPAQ).

Exclusion criteria

• Cognitive impairment precluding consent or meaningful participation.
• Lack of phone availability.
• Inability to read/write in English.
• Additional medical conditions (e.g., severe arthritis) that preclude physical activity.
• Enrollment in mind-body programs, lifestyle intervention programs (e.g., cardiac rehabilitation), or other clinical trials.