Does Parkinson's Disease Increase the Risk of Atrial Fibrillation? Insights From Electrocardiogram and Risk Scores From a Case-Control Study

Fibrinaloid Microclots and Atrial Fibrillation

Atrial fibrillation (AF) is a comorbidity of a variety of other chronic, inflammatory diseases for which fibrinaloid microclots are a known accompaniment (and in some cases, a cause, with a mechanistic basis). Clots are, of course, a well-known consequence of atrial fibrillation. We here ask the question whether the fibrinaloid microclots seen in plasma or serum may in fact also be a cause of (or contributor to) the development of AF. We consider known 'risk factors' for AF, and in particular, exogenous stimuli such as infection and air pollution by particulates, both of which are known to cause AF. The external accompaniments of both bacterial (lipopolysaccharide and lipoteichoic acids) and viral (SARS-CoV-2 spike protein) infections are known to stimulate fibrinaloid microclots when added in vitro, and fibrinaloid microclots, as with other amyloid proteins, can be cytotoxic, both by inducing hypoxia/reperfusion and by other means. Strokes and thromboembolisms are also common consequences of AF. Consequently, taking a systems approach, we review the considerable evidence in detail, which leads us to suggest that it is likely that microclots may well have an aetiological role in the development of AF. This has significant mechanistic and therapeutic implications.

Causal Relationship between Parkinson's Disease with Heart and Vascular Disease: A Two-Sample Mendelian Randomization Study

INTRODUCTION

The aim of this study was to investigate the causal relationship between Parkinson's disease (PD) and myocardial infarction (MI), atrial fibrillation and flutter (AF), and venous thromboembolism (VTE) by Mendelian randomization (MR) analysis.

METHODS

By using data from publicly available genome-wide association studies from databases, single nucleotide polymorphisms were screened as instrumental variables, and the MR analysis was finished by inverse-variance weighted (IVW), MR-egger, weighted median methods.

RESULTS

The primary IVW method showed a negative association between genetically predicted PD and risk of MI (OR = 0.9989; 95% CI: 0.9980-0.9998; p = 0.02). However, PD was not significantly associated with AF or VTE.

CONCLUSION

This study suggests a negative association between PD with MI, which implies that PD has a protective effect on MI.

Atrial fibrillation risk on Parkinson's disease - a systematic review and meta-analysis

The association of Parkinson's Disease (PD) with atrial fibrillation (AF) is not well established and previous studies' results were heterogeneous. This review aimed to evaluate if patients with PD are at increased risk of having AF. MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science, were searched from inception May 2021. Two reviewers independently selected observational studies with data allowing to estimate the risk of atrial fibrillation in PD patients compared with no-PD controls. Pooled estimates Odds Ratio (OR) and 95% confidence intervals (CIs) were derived through meta-analysis. Heterogeneity was assessed using I² test. The risk of bias of individual studies was evaluated using the ROBINS-I tool. The study protocol was registered at PROSPERO: CRD42020216572. Seven studies were included: five case-control studies and two cohort studies. Three of the studies included were a population-based study. No significant difference was detected between PD and controls regarding atrial fibrillation (OR 1.10, 95% CI 0.81 to 1.49). Early PD present a significant higher risk of AF (OR 1.55, 95% CI 1.00 to 2.40, I² 98%). The overall risk of bias was serious, with only two studies being considered as having moderate risk. The best evidence available do not support that there is an increased risk of AF in PD patients. Further studies are needed to better conclude if there is a relation between AF and PD.

Stroke in Parkinson's disease: a review of epidemiological studies and potential pathophysiological mechanisms

Parkinson's disease (PD) is the fastest growing neurological disorder and one of the leading neurological causes of disability worldwide following stroke. An overall aging global population, as well as general changes in lifestyle associated with mass industrialization in the last century, may be linked to both increased incidence rates of PD and an increase in cumulative cardiovascular risk. Recent epidemiological studies show an increased risk of stroke, post-stroke complications, and subclinical ischemic insults in PD. PD patients have a host of characteristics that might contribute to increasing the risk of developing ischemic stroke including motor impairment, dysautonomia, and sleep disorders. This increases the urgency to study the interplay between PD and other neurological disorders, and their combined effect on mortality, morbidity, and quality of life. In this review, we provide a comprehensive overview of the studied etiological factors and pathological processes involved in PD, specifically with regard to their relationship to stroke. We hope that this review offers an insight into the relationship between PD and ischemic stroke and motivates further studies in this regard.