# Characteristics of above 65-year-olds with type 1 diabetes in the Finnish diabetic nephropathy study

## TL;DR

This study explores the health characteristics of older adults with type 1 diabetes and identifies factors linked to reaching and surviving beyond 65 years.

## Contribution

The study characterizes older adults with type 1 diabetes and identifies novel associations between health factors and longevity in this age group.

## Key findings

- Higher diabetes onset age and lower HbA1c are associated with reaching older age.
- Diabetic kidney disease and cardiovascular events are linked to increased mortality in those over 65.
- Both positive and negative health factors are present in older adults with type 1 diabetes.

## Abstract

Ageing in people with type 1 diabetes is identified as a research gap. Therefore, the aim of our study is to characterize above 65-year-olds with type 1 diabetes, and to identify potential protective factors or factors related to increased risk of mortality in this age group.

This observational study includes 864 participants aged 55 years or older with type 1 diabetes (age at onset below 40) from the Finnish Diabetic Nephropathy Study, grouped according to age into three categories: 55–60, 60–65, and > 65 years old. Multivariable logistic regression analysis was used to identify factors independently associated with age above 65. Cox regression analysis was conducted to assess how these factors impact survival.

Factors that were independently associated with age above 65 years included: higher diabetes onset age, higher pulse pressure, lower mean arterial pressure, absence of current smoking and diabetic kidney disease, history of severe diabetic retinopathy and cardiovascular events, lower daily insulin dose, lower HbA1c, and lowerApoB-100 concentrations. Of these factors, the ones associated with mortality in above 65-year-olds during follow-up were presence of diabetic kidney disease, higher HbA1c, and history of cardiovascular events.

Above 65-year-olds were characterized by both factors generally related to positive and negative health outcomes. Additionally, different factors were found to be associated with reaching older age and with survival beyond the age of 65.

The online version contains supplementary material available at 10.1007/s00592-025-02613-0.