Objective: This study aimed to describe the age at onset of PD in Dhaka, Bangladesh, and the demographic and clinical characteristics of early-onset PD

Background: Parkinson’s disease (PD) is a common neurodegenerative disorder with late onset – typically after the age of sixty years, but early-onset PD is increasingly recognized and may have a different clinical and demographic profile [1]. Data on age of onset in South Asian populations are limited.

Method: This study is part of the London-Dhaka Parkinson’s Cognition Study (LDCS), a case-control study. Patients with a diagnosis of PD were recruited from Bangladesh Medical University Dhaka, from January 2023 until December 2024. Data collection included demographic and clinical information, questionnaires and clinical rating scales (e.g. MDS-Unified Parkinson’s Disease Rating Scale, RBD screening questionnaire), cognitive screening tools (e.g. Montreal Cognitive Assessment) and biospecimen collection (blood). Age at onset was defined as age at first motor symptom. Early-onset PD was defined as onset before 50 years.

Results: In this study, we included 199 patients with PD. The mean age of onset (±SD) was 55.96 (±10.66) years and 25.13% had early-onset disease (<50 years). Sex distribution did not differ significantly between early- and late-onset PD groups (p=0.37). Similarly, no significant differences were observed for smoking status (p=0.40), pesticide exposure (p=0.27), family history of PD (p=0.38), tremor-predominant phenotype (p=0.26), head injury (p=0.58), or REM sleep behavior disorder symptoms (p=0.36). Hypertension and T2DM was significantly more frequent in late-onset PD (p=0.03 and p=0.004). The time to diagnosis was also similar between the two groups (162.34 vs 179.11 days, p=0.38). Motor severity as measured by MDS-UPDRS Part III was worse for late-onset, but not statistically significant between early and late onset groups (23.26 vs 44.01, p=0.39). Cognitive performance assessed by MoCA score was significantly higher in the early-onset group compared to late-onset patients (mean 18.10 vs 15.38, p=0.02).

Conclusion: Approximately one-quarter of PD patients in this setting had early-onset disease. Early-onset PD was associated with better cognitive performance, whereas vascular comorbidities were more frequent in late-onset PD. These findings underscore the need for region-specific epidemiological data.

References: Mehanna, R., Smilowska, K., Fleisher, J., Post, B., Hatano, T., Pimentel Piemonte, M.E., Kumar, K.R., McConvey, V., Zhang, B., Tan, E.-K., Savica, R. and the International Parkinson and Movement Disorder Society Task Force on Early Onset Parkinson’s Disease (2022), Age Cutoff for Early-Onset Parkinson’s Disease: Recommendations from the International Parkinson and Movement Disorder Society Task Force on Early Onset Parkinson’s Disease. Mov Disord Clin Pract, 9: 869-878. https://doi.org/10.1002/mdc3.13523

« Back to 2026 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/assessment-of-demographic-and-clinical-characteristics-of-early-and-late-onset-parkinsons-disease-in-bangladesh/