Background: Cognitive impairment and cardiovascular dysautonomia are two major non-motor features of Parkinson's disease (PD). They have been investigated separately and extensively, but their interactive outcomes have rarely been studied.
Objective: The purpose of this study was to examine the association between central atrophy and cognition and to assess the influence of cardiovascular lability on this association in PD patients.
Methods: Out of 151 early PD patients, 47 subjects were ultimately enrolled according to our selection criteria. Their cognitive status was examined by comprehensive neuropsychological tests assessing five domains of cognition. Supine and orthostatic blood pressures were recorded during head-up tilt tests, and orthostatic mean arterial pressure change was calculated. Every patient underwent brain magnetic resonance imaging, and intercaudate nucleus ratio was obtained as a central atrophy surrogate marker. The associations and interactions between central atrophy, cognition, and blood pressure variability were analyzed.
Results: Among 47 subjects, 20 (42.6%) had orthostatic hypotension. Attention/working memory, executive function, and delayed recall were inversely associated with central atrophy (r = -0.332, p = 0.028; r = -0.314, p = 0.038; r = -0.399, p = 0.024; respectively). In a multiple regression model, only attention/working memory was independently associated with central atrophy when modulated by orthostatic mean arterial pressure change (p < 0.05).
Conclusion: This study revealed that cardiovascular dysautonomia interacted with the inverse association between cerebral atrophy and cognition, and it reinforced its relationship. Interaction between these two non-motor features should be kept in mind in clinical practice, particularly in PD patients with co-morbid vascular factors.
Keywords: Parkinson’s disease; cardiovascular dysautonomia; cognition; subcortical atrophy.