The investigators developed a novel, telephone-based, 12-week positive psychology intervention and will assess its feasibility and short-term impact in adults with type 2 diabetes (T2D) and suboptimal health behavior adherence. Participants will receive a positive psychology (PP) manual, complete exercises (e.g., writing a gratitude letter, performing acts of kindness), and review these activities by phone with a study trainer over the 12-week study period.

Specific Aim #1 (Feasibility and acceptability (immediate impact); primary aim): To assess whether PP exercises administered over the phone are feasible and linked with immediate benefit in patients with T2D, as measured by ratings provided pre- and post- each exercise.

Hypothesis: The PP exercises will be feasible (i.e., 4 of the 7 PP exercises will be completed by a majority of participants, and participants will have a mean score of at least 7 out of 10 on ratings of ease of completion for the exercises. The PP exercises will also have adequate immediate impact (i.e., mean ratings of 7/10 of exercise utility post-exercise and ratings of optimism post-exercise that are significantly higher than pre-exercise).

Specific Aim #2 (Changes in clinical outcome measures): To determine whether the PP intervention is linked to improvements in psychological well-being, during and after the intervention period (6 & 12 weeks), via measures of optimism, gratitude, depression, and anxiety. To examine whether the brief PP intervention is associated with improvements in self-reported outcomes related to health (diabetes self-care, diabetes distress, health related quality of life), during and after the intervention.

Hypothesis: Participants will have higher mean scores on all psychological outcome measures at 6 and 12 weeks compared to baseline. Participants will also have higher mean scores on all health-related outcome measures at 6 and 12 weeks compared to baseline.

This is a pilot and feasibility study in adult inpatients and outpatients at MGH. Participants will have Type 2 Diabetes (T2D) and are required to report suboptimal adherence to health behaviors, measured by the Medical Outcomes Study Specific Adherence Scale (MOS SAS). All participants will receive a 12-week PP intervention and pre- and post-intervention assessments of mood and physical symptoms.

Participants will be enrolled from the outpatient Diabetes Center and inpatient medical units of MGH; research staff will introduce the study, assess for inclusion and exclusion criteria, and obtain written informed consent. Post-enrollment, and prior to initiation of the intervention, participants will complete baseline self-report measures of clinical outcomes.

During the initial enrollment visit, participants will receive a treatment manual. In person or by telephone, the study interventionist will review the introductory portion of the manual and discuss the first exercise (Gratitude for Positive Events) with the participant. In subsequent weeks, exercises will be completed independently by participants, recorded in their treatment manual, and then discussed over the phone with their trainer. In the final week, after the final exercise is reviewed, the interventionist and participant will discuss future implementation and ways to incorporate the principles into daily life.

The 12-week intervention will consist of 7 distinct PP exercises, to be completed weekly for the first 4 weeks and then biweekly over the next 8 weeks.

For feasibility, interventionists will record rates of exercise completion at each participant phone session. For acceptability, participants will rate their optimism and positive affect on a 0-10 scale prior to completing the exercise and then immediately following the exercise. Additionally, participants will also rate the ease and overall utility of the exercise on a 0-10 scale after each exercise.

At baseline, 6 weeks, and 12 weeks, non-interventionist study staff obtained the following validated measures of study outcomes:

• Optimism = Life Orientation Test-Revised (LOT-R)
• Gratitude = Gratitude Questionnaire-6 (GQ-6)
• Anxiety and depression = Hospital Anxiety and Depression Scale (HADS)
• Diabetes-related distress = Diabetes Distress Scale (DDS)
• Health-related quality of life and function = Patient-Reported Outcomes Measurement Information System physical function scale (PROMIS-PF-10)
• Diabetes self-care behaviors = Summary of Diabetes Self-Care Activities Measure (SDSCA)
• Health behavior adherence = Medical Outcomes Study Specific Adherence Scale (MOS SAS)

Inclusion Criteria:

• Current patient of the MGH Diabetes Center or inpatient on Ellison 9-11, White 8-11, Ellison 16, or Bigelow 11
• Diagnosis of type 2 Diabetes (confirmed via medical record and patient's treatment provider)
• Age 18 and older
• Able to read/write in English
• Suboptimal adherence, defined as a score of 15 or less on three Medical Outcomes Study Specific Adherence Scale (MOS SAS) items related to adherence to medications, diet, and exercise.

Exclusion Criteria:

• Cognitive disorder precluding informed consent or meaningful participation in the PP exercises, assessed using a six-item cognitive screen developed for research.
• Lack of telephone access