Epigenetic aging clocks and cognitive status in the Parkinson's Progression Markers Initiative
In the Parkinson's Progression Markers Initiative cohort, higher epigenetic aging from blood DNA methylation was consistently linked to lower overall MoCA cognition scores; the signal came mainly from differences between people at baseline, not from short-term cognitive change within people. [1]
Automatic summary · not editorially reviewed
The key findings
Seven epigenetic aging measures were derived from peripheral blood DNA methylation data, and cognition was assessed longitudinally with the Montreal Cognitive Assessment in the Parkinson's Progression Markers Initiative cohort. [1]
Higher epigenetic aging was consistently associated with lower overall MoCA scores. [1]
Associations were concentrated in the between-person component, while within-person deviation terms were not significant, and the authors suggest epigenetic aging may mark cognitive status more than short-term progression. [1]
The source at a glance
- Study type / format
- Cohort study using linear mixed-effects models (abstract only)
- Population / context
- Participants in the Parkinson's Progression Markers Initiative cohort with peripheral blood DNA methylation data and longitudinal MoCA cognitive assessments.
- Summary based on
- Study abstract
- Original publication
- September 1, 2026
Cognition versus decline in the PPMI cohort
The study asked whether blood-based epigenetic aging measures mainly reflect stable differences in cognitive performance between people or longitudinal cognitive change. Cognitive impairment is described as a major source of disability in Parkinsonian disorders, while biomarkers separating cognitive status from cognitive decline remain limited. Cognition was assessed longitudinally with the Montreal Cognitive Assessment (MoCA), and seven epigenetic aging measures were derived from peripheral blood DNA methylation data in the Parkinson's Progression Markers Initiative cohort.
Supporting source [1]
Between-person signal dominates over within-person change
Higher epigenetic aging was consistently associated with lower overall MoCA scores. In models combining baseline and change from baseline, the baseline component carried the dominant signal, while change-from-baseline terms were not significant after false discovery rate correction. In decomposition models, associations were concentrated in the between-person component, and within-person deviation terms were not significant. Secondary analyses were consistent with this pattern. These are associations, not evidence that epigenetic aging causes cognitive differences.
Supporting source [1]
Abstract-only scope and need for longer follow-up
The authors conclude that blood-based epigenetic aging measures may be more informative as markers of cognitive status than as markers of short-term cognitive progression. They call for larger studies with longer follow-up and more detailed domain-specific cognitive phenotyping to clarify longitudinal relevance. This explainer is based only on the abstract; the full text was not reviewed, so details of the cohort, follow-up duration and model specifications are not assessed here.
Supporting source [1]
How to interpret this
Abstract only; the full text was not reviewed. Cohort size, follow-up duration, model details and domain-specific cognitive results are not reported in the supplied text and are not assessed here. Findings are associations, not causal evidence.
Based on the study abstract; the full paper, tables and supplementary data were not reviewed.
Source & supporting passages
Feng B, Gao A, Yang J. · europepmc.org · September 1, 2026