Longitudinal changes in health-related quality of life in normal glucose tolerance, prediabetes and type 2 diabetes: results from the KORA S4/F4 cohort study

Abstract

Purpose: The aim of this study was to examine how transition between normal glucose tolerance, prediabetes and diabetes over a 7 year period is associated with change in health-related quality of life (HRQL) in an elder German population-based cohort.

Methods: We used data from 1,046 participants of the KORA S4/F4 cohort study aged 55-74 years at baseline. Based on an oral glucose tolerance test, prediabetes was defined as impaired fasting glucose and/or impaired glucose tolerance. HRQL was assessed with the SF-12 questionnaire. Using linear regression, we estimated mean change in HRQL over time, depending on glucose status at baseline and follow-up, adjusted by demographic and lifestyle variables.

Results: Individuals progressing to prediabetes or diabetes experienced a greater loss in the physical component score than patients with persistent normal glucose tolerance (-2.31 and -7.44 vs. -1.08), but the difference was only significant for subjects converting to diabetes. Subjects with prediabetes at baseline and diabetes at follow-up had a significant loss in mental health compared to subjects with persistent prediabetes.

Conclusions: There is first evidence that worsening of glucose metabolism over time is associated with deteriorating HRQL, however, further and larger longitudinal studies are needed to confirm these findings.