Background: Mild parkinsonian signs (MPS) are common in the older adult and associated with a wide range of adverse health outcomes. There is limited data on the prevalence of MPS and its significance.
Objective: To determine the prevalence of MPS in the community ambulant population and to evaluate the relationship of MPS with prodromal features of Parkinson's disease (PD) and cognition.
Methods: This cross-sectional community-based study involved participants aged ≥50 years. Parkinsonian signs were assessed using the modified Unified Parkinson's Disease Rating Scale (mUPDRS) and cognition using the Montreal Cognitive Assessment (MoCA). Premotor symptoms of PD were screened using a self-reported questionnaire. Linear regression was used to assess the association of MPS with premotor symptoms of PD and cognitive impairment.
Results: Of 392 eligible participants, MPS was present in 105 (26.8%). Mean age of participants with MPS was 68.8±6.9 years and without MPS was 66.1±5.9 years (p < 0.001). Multivariate analysis revealed that MoCA scores were significantly lower in the MPS group (β= -0.152, 95% CI = -0.009, -0.138, p < 0.05). A significant correlation between the presence of REM sleep behavior disorder (RBD) and total MPS scores (β= 0.107, 95% CI = 0.053, 1.490, p < 0.05) was also found. Neither vascular risk factors nor other premotor symptoms were significantly associated with MPS.
Conclusion: MPS is common and closely related to cognitive impairment and increasing age. Presence of RBD is predictive of higher MPS scores. This study highlights the necessity of other investigations or sensitive risk markers to identify subjects at future risk of PD.
Keywords: Mild parkinsonian signs; REM sleep behavior disorder (RBD); premotor symptoms.