Association of social isolation, loneliness, and their trajectory with incident type 2 diabetes across genetic risk

Abstract

Abstract Background Emerging evidence concerning the association of social isolation and loneliness with diabetes risk were inclusive. It remains unknown how social isolation, loneliness, and their change, were associated with the onset of type 2 diabetes. This study aimed to investigate the association of social isolation, loneliness, and their trajectory with the risk of developing type 2 diabetes across genetic risk. Methods We included 439,337 participants (mean age 56.3 ± 8.1 years) enrolled in the UK Biobank study who were followed up until May 31, 2021. Social isolation and loneliness were self-reported. In a longitudinal analysis, based on baseline (2006–2010) and follow-up (2012–2020) data, social isolation and loneliness were further categorized into never, transient, incident, and persistent patterns. Results During a median follow-up of 12.7 years, 15,258 incident type 2 diabetes cases were documented. Most isolated [vs. least isolated; hazard ratio (HR) 1.09; 95% confidence interval [CI] 1.04–1.14]) and loneliness (vs. no loneliness; 1.21 [1.14–1.29]) were associated with an increased type 2 diabetes risk, independent of the genetic risk for type 2 diabetes. An interaction existed between social isolation and loneliness (P interaction = 0.005); the increased type 2 diabetes risk associated with social isolation was only significant among participants without loneliness. In the longitudinal analysis, only persistent social isolation (vs. never social isolation; 1.21 [1.02–1.44]) was associated with an increased type 2 diabetes risk, whereas incident loneliness (vs. never loneliness; 1.96 [1.40–2.73]) and persistent loneliness (1.65 [1.09–2.52]) were associated with higher type 2 diabetes risks. Conclusions Social isolation and loneliness, especially their persistent pattern, were independently associated with an increased incident type 2 diabetes risk, irrespective of an individual’s genetic risk. Loneliness modified the association between social isolation and incident type 2 diabetes.