All-cause mortality, cardiovascular and microvascular diseases in latent autoimmune diabetes in adults

Objective: Latent autoimmune diabetes in adults (LADA) is a heterogenous, slowly progressing autoimmune diabetes. We aim to contribute new knowledge on the long-term prognosis of LADA with varying degrees of autoimmunity by comparing it to type 2 diabetes and adult-onset type 1 diabetes.

Study design and methods: This Swedish population-based study included newly diagnosed LADA (n=550, stratified into LADA^low and LADA^high by median autoimmunity level), type 2 diabetes (n=2001), adult-onset type 1 diabetes (n=1573), and diabetes-free controls (n=2355) in 2007-2019. Register linkages provided information on all-cause mortality, cardiovascular diseases (CVD), diabetic retinopathy, nephropathy, and clinical characteristics during follow-up.

Results: Mortality was higher in LADA (hazard ratio [HR]: 1.44; 95% CI: 1.03, 2.02), type 1 (2.31 [1.75, 3.05]) and type 2 diabetes (1.31 [1.03, 1.67]) than in controls. CVD incidence was elevated in LADA^high (HR 1.67 [1.04, 2.69]) and type 2 diabetes (1.53 [1.17, 2.00]), but not in LADA^low or type 1 diabetes. Incidence of retinopathy but not nephropathy was higher in LADA (HR 2.25 [1.64, 3.09]) including LADA^high and LADA^low than in type 2 diabetes (unavailable in type 1 diabetes). More favorable blood pressure and lipid profiles but higher HbA1c levels were seen in LADA than type 2 diabetes at baseline and throughout follow-up, especially in LADA^high which resembled type 1 diabetes in this respect.

Conclusion: Despite having fewer metabolic risk factors than type 2 diabetes, LADA has equal to higher risks of death, CVD, and retinopathy. Poorer glycemic control, particularly in LADA^high, highlights the need for improved LADA management.