The focus of this study is to examine the feasibility, acceptability, and preliminary impact of a customized, combined positive psychology and motivational interviewing (PP-MI) health behavior intervention in a group of patients with type 2 diabetes (T2D).

The investigators are proposing a study that will specifically and innovatively focus on the development of a novel positive psychology intervention that is adapted for patients with T2D. The MGH Diabetes Center and MGH primary care clinics will serve as the source of subjects for the study, with patients who have a diagnosis of T2D serving as potential subjects. The investigators will enroll 12 T2D patients, who will take part in an 16-week PP-MI health behavior intervention.

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

1. Test a 16-week, telephone-delivered health behavior intervention utilizing PP exercises and systematic goal-setting in a brief, non-randomized, proof-of concept trial (N=12).
2. Determine whether this initial intervention is feasible in a small cohort of T2D patients.
3. Explore potential benefits of the intervention on outcomes of interest (e.g., optimism, positive affect).

Baseline information about enrolled participants will be obtained from the patients, 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 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 nurses in the Translational and Clinical Research Center will collect vital signs and draw blood for A1c. To ensure that participants have low baseline physical activity, they will then take home and wear accelerometers for 1 week.

Participants will undergo a second in-person visit to confirm that participants are eligible to complete the program and--if so--to initiate the program. During this session, A1c and accelerometer data will be reviewed. Participants will be required to have an A1c value between 6.5% and 9%, unless they have had an eligible A1c level in the past 6 months, in which case their current A1c may be between 6% and 9.5%. Furthermore, participants must have low physical activity (< 75 minutes of moderate or vigorous physical activity over the past week, measured by accelerometer) to continue in the program. Upon confirmation of eligibility, participants will begin the study intervention.

During this second in-person visit, participants will receive a PP-MI treatment manual. 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. Interventionists will complete PP exercise 1 and MI session 1 together with participants to aid engagement. Interventionists will also explain/assign PP exercise 2 and discuss an MI-based activity goal matched to participants' stage of change and medical recommendations (and assign activity tracking).

Participants will complete the remaining sessions (14 in total) by phone over the next 16 weeks. Phone sessions will last for approximately 30 minutes, with PP and physical activity assignments completed between phone sessions. PP and MI components will be delivered stepwise 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 skip 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 final in-person visit. Finally, prior to this assessment, participants will wear an accelerometer for an additional 7 days to measure moderate or vigorous physical activity. The investigators will allow a window of 3 weeks, to allow flexibility of scheduling such in-person appointments in Boston (and to allow coordination with other medical visits at MGH) while maintaining integrity of study findings.

Inclusion Criteria:

• T2D. Eligible patients will be diagnosed with T2D, with diagnosis for at least 1 year, confirmed by their diabetes clinician or medical record review. Consistent with American Diabetes Association (ADA) criteria for T2D, participants must have HbA1c [A1C] of at least 6.5% within the last 6 months. The investigators will exclude patients with A1C>9% given that patients in this range will likely have more extreme nonadherence and/or require ongoing treatment adjustment, increasing the heterogeneity of this sample for this pilot project. If patients appear otherwise eligible, but do not have an A1C value within 6 months, they will be required to have a baseline A1C value of 6.5-9%.
• Low physical activity. The investigators will define low physical activity as ≤75 minutes/week of MVPA (representing ≤40% of ADA recommendations for moderate or greater intensity aerobic physical activity totaling 150 minutes per week). This cutoff allows adequate room for improvement on this key outcome. As an initial screen, the investigators will use a modified version of the International Physical Activity Questionnaire (IPAQ) which has been extensively used/validated in medical cohorts, including T2D. Patients will complete the modified IPAQ regarding their activity in the past week (or a typical week, if the past 7 days atypical) to assess number of minutes spent performing MVPA. Patients reporting ≤60 minutes/week of MVPA will then wear accelerometers for 7 days to confirm low physical activity.
• Prescribed an oral glucose-lowering drug or choosing lifestyle interventions (diet and exercise) to manage T2D. To be eligible, patients must be prescribed a stable glucose-lowering medication regimen (or stable plan for control with diet/exercise alone) for at least 3 months with no anticipated adjustment. Including those whose T2D is managed by diet and exercise alone will allow inclusion of participants who may have high likelihood of engagement in a behavioral intervention. The investigators will exclude patients taking insulin to reduce heterogeneity of T2D severity in this initial trial.

Exclusion Criteria:

• Cognitive impairment precluding consent or meaningful participation, assessed using a six-item screen developed for this purpose.
• Lack of phone availability.
• Inability to read/write in English.
• Additional medical conditions (e.g., severe arthritis, chronic pulmonary obstructive disease, class III or IV heart failure) that preclude physical activity.
• Enrollment in mind-body programs, lifestyle intervention programs (e.g., cardiac rehabilitation), or other clinical trials.