A medRxiv preprint study from the United Kingdom has shown that Parkinson’s disease progresses at a much faster rate in patients in the presence of type 2 diabetes.

The study analysed data from 1930 adults with recent-onset Parkinsons disease, who had been enrolled in the Tracking Parkinson’s Registry within 3.5 years of their diagnosis. The diagnosis of type 2 diabetes was self-reported by patients at study entry. Various scales used to assess Parkinson’s disease included the Movement Disorders Society Unified Parkinson’s Disease Rating Scale (MDS-UPDRS), Non-Motor Symptoms Scale (NMSS), Montreal Cognitive Assessment (MoCA), Questionnaire for impulsive-compulsive disorders in PD (QUIP), Leeds Anxiety and Depression Scale (LADS), and Schwab and England ADL scale.

“The Tracking Parkinson’s study is the worlds largest long-term study into Parkinsons disease. It is an observational study based in the UK collecting clinical data and biosamples from over 2,500 participants since 2012” (https://www.trackingparkinsons.org.uk/).

Type 2 diabetes was detected as a comorbid condition in 167 (~9%) patients with Parkinson’s disease; 1763 (91.3%) patients did not have type 2 diabetes.

It was seen that during the average follow-up of almost 38 months, the MDS-UPDS III scores were higher in patients with type 2 diabetes; 25.8 versus 22.5, respectively indicating greater severity of motor symptoms as well as faster motor symptom progression over the course of time. Parkinson’s patients with coexisting diabetes were more at risk of developing marked impairment of gait (HR 1.55), loss of independence (OR 2.08), mild cognitive impairment (HR 1.7) and depression (OR 1.62); their mood worsened over time compared to those who had Parkinson’s disease alone.

This prospective study has demonstrated an interrelationship between the two disease conditions. Not only are type 2 diabetes patients at increased risk of developing Parkinson’s disease, the disease progression is also significantly faster in them, with development of gait impairment, cognitive impairment, depression above and beyond the more severe motor symptoms. Type 2 diabetes is a new potentially modifiable factor, which affects both motor and nonmotor symptoms. A well-controlled glycemic status therefore may improve symptoms of Parkinson’s by checking disease progression and prevent or delay onset of disability and/or dementia.

Reference

1. Athauda D, et al. The impact of type 2 diabetes in Parkinson’s disease. medRxiv Posted October 26, 2021. doi: https://doi.org/10.1101/2021.