A pilot study of an integrated mental health, social and medical model for diabetes care in an inner-city setting: Three Dimensions for Diabetes (3DFD)

Diabet Med. 2020 Oct;37(10):1658-1668. doi: 10.1111/dme.13918. Epub 2019 May 7.


Aims: We examined the effectiveness of a service innovation, Three Dimensions for Diabetes (3DFD), that consisted of a referral to an integrated mental health, social care and diabetes treatment model, compared with usual care in improving biomedical and health economic outcomes.

Methods: Using a non-randomized control design, the 3DFD model was offered in two inner-city boroughs in London, UK, where diabetes health professionals could refer adult residents with diabetes, suboptimal glycaemic control [HbA1c ≥ 75 mmol/mol (≥ 9.0%)] and mental health and/or social problems. In the usual care group, there was no referral pathway and anonymized data on individuals with HbA1c ≥ 75 mmol/mol (≥ 9.0%) were collected from primary care records. Change in HbA1c from baseline to 12 months was the primary outcome, and change in healthcare costs and biomedical variables were secondary outcomes.

Results: 3DFD participants had worse glycaemic control and higher healthcare costs than control participants at baseline. 3DFD participants had greater improvement in glycaemic control compared with control participants [-14 mmol/mol (-1.3%) vs. -6 mmol/mol (-0.6%) respectively, P < 0.001], adjusted for confounding. Total follow-up healthcare costs remained higher in the 3DFD group compared with the control group (mean difference £1715, 95% confidence intervals 591 to 2811), adjusted for confounding. The incremental cost-effectiveness ratio was £398 per mmol/mol unit decrease in HbA1c , indicating the 3DFD intervention was more effective and costed more than usual care.

Conclusions: A biomedical, psychological and social criteria-based referral system for identifying and managing high-cost and high-risk individuals with poor glycaemic control can lead to improved health in all three dimensions.

Publication types

  • Controlled Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Delivery of Health Care / economics
  • Delivery of Health Care / organization & administration*
  • Diabetes Mellitus, Type 1 / economics
  • Diabetes Mellitus, Type 1 / metabolism
  • Diabetes Mellitus, Type 1 / psychology
  • Diabetes Mellitus, Type 1 / therapy*
  • Diabetes Mellitus, Type 2 / economics
  • Diabetes Mellitus, Type 2 / metabolism
  • Diabetes Mellitus, Type 2 / psychology
  • Diabetes Mellitus, Type 2 / therapy*
  • Female
  • Glycated Hemoglobin A / metabolism
  • Health Care Costs
  • Health Services / economics
  • Health Services Administration
  • Humans
  • London
  • Male
  • Mental Disorders / psychology
  • Mental Disorders / therapy*
  • Mental Health Services / economics
  • Mental Health Services / organization & administration*
  • Middle Aged
  • Pilot Projects
  • Social Work / economics
  • Social Work / organization & administration*
  • Urban Population


  • Glycated Hemoglobin A
  • hemoglobin A1c protein, human