Diabetes, Glycated Hemoglobin (HbA1c), and Neuroaxonal Damage in Parkinson's Disease (MARK‐PD Study)

Abstract

Background Diabetes is associated with incidence and prevalence of Parkinson's disease (PD). Furthermore, glycated hemoglobin (HbA1c) levels have been linked with motor function and progression. Objectives We evaluated the relationship between prevalent diabetes and HbA1c levels with serum neurofilament light chain (NfL) levels as marker of neuroaxonal damage. Methods NfL concentrations were analyzed with Simoa in serum of 195 PD patients with available HbA1c values. Motor (MDS‐UPDRS III, Hoehn & Yahr [H&Y]) and cognitive (Montreal Cognitive Assessment [MoCA]) function was assessed and vascular comorbidities were documented from medical records. Results PD patients with prevalent diabetes had higher serum NfL levels and lower MoCA scores independent of age, body mass index (BMI), and vascular risk factors. Furthermore, diabetes was associated with higher H&Y stages in unadjusted and age/BMI‐adjusted models. Higher HbA1c levels were associated with increased NfL in unadjusted and age/BMI‐adjusted models. Conclusions In PD patients, diabetes and high HbA1c are associated with increased neuroaxonal damage and cognitive impairment. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson Movement Disorder Society.

Diabetes and neuroaxonal damage in Parkinson’s disease

“…We read with interest Uyar and colleagues’ recent report on the association between diabetes, non-diabetic elevated glycated hemoglobin levels (HbA1c) and neuroaxonal damage in PD patients from the MARK-PD study. (1) The authors confirmed previously established findings of an inverse association between diabetes and cognitive and motor status. The authors also demonstrated higher serum neurofilament light (NfL) levels (a marker of neuroaxonal damage) (2) in PD patients with prevalent type 2 diabetes and in PD patients with non-diabetic elevated HbA1c levels.…”

Reply to: “Diabetes and Neuroaxonal Damage in Parkinson's Disease”

“…We appreciate the letter by Vijiaratnam and colleagues, which confirms the association of diabetes with increased neuronal damage in patients with Parkinson's disease (PD) independent of age, body mass index, and vascular risk factors 1 . PD patients with diabetes revealed increased serum neurofilament light (sNfL) chain levels in both the biomarkers in Parkinson's disease (MARK‐PD) and Tracking Parkinson's Disease studies 1,2 . However, disease duration was much longer (12 years vs. 1 year), Hoehn & Yahr stage was more advanced (2.5 vs. 1.8), and Movement Disorder Society–Sponsored Revision of the Unified Parkinson's Disease Rating Scale III score was slightly higher (26 vs. 23) in the MARK‐PD study, whereas age and Montreal Cognitive Assessment scores were identical (ie, 68 years and 25 points, respectively) 1,2 .…”

“…PD patients with diabetes revealed increased serum neurofilament light (sNfL) chain levels in both the biomarkers in Parkinson's disease (MARK‐PD) and Tracking Parkinson's Disease studies 1,2 . However, disease duration was much longer (12 years vs. 1 year), Hoehn & Yahr stage was more advanced (2.5 vs. 1.8), and Movement Disorder Society–Sponsored Revision of the Unified Parkinson's Disease Rating Scale III score was slightly higher (26 vs. 23) in the MARK‐PD study, whereas age and Montreal Cognitive Assessment scores were identical (ie, 68 years and 25 points, respectively) 1,2 . Despite these differences, prevalent diabetes was associated with increased neuronal damage quantified by sNfL in early‐ and late PD underlining the robustness of this finding.…”

Diabetes and Neuroaxonal Damage in Parkinson's Disease

“…We appreciate the letter by Vijiaratnam and colleagues, which confirms the association of diabetes with increased neuronal damage in patients with Parkinson's disease (PD) independent of age, body mass index, and vascular risk factors. 1 PD patients with diabetes revealed increased serum neurofilament light (sNfL) chain levels in both the biomarkers in Parkinson's disease (MARK-PD) and Tracking Parkinson's Disease studies. 1,2 However, disease duration was much longer (12 years vs. 1 year), Hoehn & Yahr stage was more advanced (2.5 vs. 1.8), and Movement Disorder Society-Sponsored Revision of the Unified Parkinson's Disease Rating Scale III score was slightly higher (26 vs. 23) in the MARK-PD study, whereas age and Montreal Cognitive Assessment scores were identical (ie, 68 years and 25 points, respectively).…”

“…1 PD patients with diabetes revealed increased serum neurofilament light (sNfL) chain levels in both the biomarkers in Parkinson's disease (MARK-PD) and Tracking Parkinson's Disease studies. 1,2 However, disease duration was much longer (12 years vs. 1 year), Hoehn & Yahr stage was more advanced (2.5 vs. 1.8), and Movement Disorder Society-Sponsored Revision of the Unified Parkinson's Disease Rating Scale III score was slightly higher (26 vs. 23) in the MARK-PD study, whereas age and Montreal Cognitive Assessment scores were identical (ie, 68 years and 25 points, respectively). 1,2 Despite these differences, prevalent diabetes was associated with increased neuronal damage quantified by sNfL in early-and late PD underlining the robustness of this finding.…”