Social Isolation, Loneliness, and Risk of Microvascular Complications Among Individuals With Type 2 Diabetes Mellitus

Rationale & ObjectiveSocial disconnection has been associated with poor cardiometabolic health. This study sought to investigate the associations of social isolation and loneliness with diabetic microvascular complications (DMC) among individuals with type 2 diabetes mellitus (T2DM) and compare these associations to those related to traditional risk factors.Study DesignProspective cohort study.Setting & ParticipantsA total of 24,297 UK Biobank participants with T2DM and no DMC at baseline.ExposureSocial isolation and loneliness measured using self-reported questionnaires.OutcomeThe incidence of DMC defined as a composite of diabetic kidney disease, diabetic retinopathy, or diabetic neuropathy.Analytical ApproachMultivariable cause-specific hazards regression. To compare the relative importance of social disconnection with other established factors, the R2 values of the Cox models were calculated.ResultsDuring a median follow-up of 12.6 years, 5,530 patients were documented to develop DMC (3,458 with diabetic kidney disease, 2,255 with diabetic retinopathy, and 1,146 with diabetic neuropathy). The highest level of social isolation was associated with an increased risk of any DMC component (most vs. least: HR: 1.13; 95% CI: 1.05-1.22), especially diabetic kidney disease (HR: 1.14, 95% CI: 1.04-1.25) and neuropathy (HR: 1.31, 95% CI: 1.11-1.53). Any level of loneliness was associated with an increased risk of any DMC component (HR: 1.12; 95% CI: 1.02-1.23) and diabetic kidney disease (HR: 1.16, 95% CI: 1.03-1.30). Social isolation and loneliness exhibited associations with DMC comparable to other conventional risk factors including smoking, blood pressure, and physical activity.LimitationsLimited generalizability related to the composition of participants in the UK Biobank Study.ConclusionsSocial isolation and loneliness were independently associated with a higher risk of incident DMC among individuals with T2DM, with comparable importance to other traditional risk factors. These findings underscore social isolation and loneliness as novel and potentially modifiable risk factors for DMC.