Type 2 diabetes mellitus in people with intellectual disabilities: Examining incidence, risk factors, quality of care and related complications. A population-based matched cohort study

Abstract

Aims
People with intellectual disabilities are at higher risk of type 2 diabetes mellitus (T2DM) but there are currently gaps in our understanding related to risk of new onset, care of T2DM and complications.

Methods
We examined electronic health-record data from Jan 2010 to May 2022 in 189,172 people with intellectual disabilities and 306,697 age, sex and family practice matched controls. We estimated incidence rates per 1,000-person-years, incidence rate ratios (IRRs), risk factors for T2DM (odds ratio, OR), indicators of quality of care and complications (hazard ratio, HR).

Results
Incidence of T2DM in people with intellectual disabilities was 3.74 compared to 2.21 per 1,000 person-years in controls. After allowing for the younger age of T2DM onset in intellectual disabilities, the adjusted IRR was 6.91 (95 % CI 5.81–8.22). Impaired mobility was associated with T2DM incidence in people with intellectual disabilities (OR = 7.72, 5.87–10.15). People with intellectual disabilities received blood tests for HbA1c and cholesterol, and eye and foot examinations less often; and had a 12 % higher risk of developing macrovascular complications.

Conclusions
People with intellectual disabilities are at increased risk of T2DM at younger ages, have specific risk factors, experience inequities in care and are at risk for macrovascular complications.