The effect of type 2 diabetes diagnosis in the elderly

In this paper, I use a novel approach based on biomarkers data to examine the effect of type 2 diabetes (T2D) diagnosis on both physical and mental health for a sample of individuals aged 50 and above. In order to retrieve reliable estimates, I exploit the fact that medical guidelines cause a discontinuity in the probability that General Practitioners (GP) diagnose their patients with T2D as a function of exact blood test cut-off in a regression discontinuity design (RDD) approach. Using data from the English Longitudinal Study of Ageing (ELSA), I find compelling evidence that health information, in the form of T2D diagnosis, influences the protection of health into old age. Specifically, after receiving T2D diagnosis, over time, individuals reported a 2.1 lower body mass index (BMI) as well as 5.5 cm lower waist circumference, relative to their counterparts. With respect to self-reported physical health, the results imply that those diagnosed with T2D reported a 0.19 and 0.70 higher score in increased activities of daily living (ADL) and body mobility indexes, respectively. Finally, while I find evidence that T2D-diagnosed patients reported a significant, 0.5 higher, score in the word listening test, I find no evidence that T2D diagnosis impacted self-reported depression levels. I provide a wide variety of evidence on the validity of the results.