Persons with latent autoimmune diabetes in adults express higher dipeptidyl peptidase-4 activity compared to persons with type 2 and type 1 diabetes

- Difference in DPP-4 activity exists between persons with T1, T2 diabetes and LADA.
- Dipeptidyl peptidase-4 activity is highest in persons with latent autoimmune diabetes in adults.
- Dipeptidyl peptidase-4 activity correlates with glutamic acid autoantibody.
- Dipeptidyl peptidase-4 inhibitors might be considered in treatment of autoimmune diabetes.

AimsWe aimed to determine serum dipeptidyl peptidase-4 (DPP-4) activity in a group of persons with latent autoimmune diabetes in adults (LADA) and to compare it with persons with type 1, type 2 diabetes and healthy controls.MethodsDPP-4 activity measurement was performed in 67 persons (21 with type 1, 26 type 2 and 19 with LADA) and 13 healthy age and gender matched controls.ResultsPersons with LADA showed highest DPP-4 activity among the study groups (32.71 ± 3.55 vs 25.37 ± 2.84 vs 18.57 ± 2.54 vs 18.57 ± 2.61 U/L p < 0.001). Mean glutamic acid autoantibody in persons with LADA was 164.32 ± 86.28 IU/mL. It correlated with DPP-4 activity (r = 0.484, p = 0.013). Furthermore, DPP-4 activity correlated with waist circumference (r = 0.279, p = 0.034) and glycated haemoglobin A1c (r = 0.483, p < 0.001), as well as with LDL cholesterol (r = 0.854, p < 0.001) and total daily insulin dose (r = 0.397, p = 0.001). In the multinomial regression analysis DPP-4 activity remained associated with both LADA (prevalence ratio 1.058 (1.012-1.287), p = 0.001) and type 1 diabetes (prevalence ratio 1.506 (1.335-1.765), p < 0.001) while it did not show an association with type 2 diabetes (prevalence ratio 0.942 (0.713-1.988), p = 0.564).ConclusionsPersons with LADA express higher DPP-4 activity compared to persons with both type 1 and type 2 diabetes. The possible pathophysiological role of DPP-4 in the LADA pathogenesis needs to be further evaluated.