Comparative characteristics of older people with type 1 diabetes treated with continuous subcutaneous insulin infusion or insulin injection therapy: data from the German/Austrian DPV registry

Abstract

Aim: To compare clinical characteristics and outcomes in adults with type 1 diabetes aged ≥ 60 years using continuous subcutaneous insulin infusion (CSII) vs. insulin injection therapy. Further, to determine the percentage of older adults with type 1 diabetes using CSII.

Research design and methods: Retrospective study using data of the Diabetes Prospective Follow-up Registry (DPV). Including percentage CSII use from 2008 to 2018, and the characteristics of 9547 individuals extracted from the DPV in March 2019 (N = 1404 CSII; N = 8143 insulin injection therapy). Wilcoxon rank sum tests were used for continuous variables and chi-square tests for categorical variables to compare clinical characteristics of people using CSII vs. insulin injection therapy. Adjusted analyses used generalized linear models to compare diabetes-related outcomes.

Results: CSII usage has increased in older adults (from 12% in 2008 to 23% in 2018). After adjustment, CSII was associated with lower HbA_1c [60.7 mmol/mol (7.7 ± 0.1%) vs. 62.8% (7.9 ± 0.1%)], lower daily insulin dose (0.49 ± 0.02 vs. 0.61 ± 0.01 IU/kg), fewer days in hospital (8.1 ± 0.12 vs. 11.2 ± 0.11 days/person-year), fewer severe hypoglycaemic events (0.16 ± 0.02 vs. 0.21 ± 0.03 events/person-year) and fewer diabetic ketoacidosis (0.06 ± 0.01 vs. 0.08 ± 0.01 events/person-year). Individuals on CSII showed lower rates of microalbuminuria and also have a diagnosis of depression and neuropathy.

Conclusions: A growing number of older adults are using insulin pumps. Older age in itself should not be seen as a contraindication for CSII.