Abstract: Background: Physical activity is associated with reduced risk of Parkinson’s disease (PD). The explanations for this association are not completely elucidated. We use long-term PD-incidence data from long-distance skiers to study the relationship between exercise and PD. Objective: We aimed to investigate if physical activity is associated with long-term lower risk of PD and if this association could be explained by physically active people being able to sustain more PD neuropathology before clinical symptoms, a motor reserve. Methods: Using a prospective observational design, we studied whether long-distance skiers of the Swedish Vasaloppet (n = 197,685), exhibited reduced incidence of PD compared…to matched individuals from the general population (n = 197,684) during 21 years of follow-up (median 10, interquartile range (IQR) 5–15 years). Results: Vasaloppet skiers (median age 36.0 years [IQR 29.0–46.0], 38% women) had lower incidence of PD (HR: 0.71; 95 % CI 0.56–0.90) compared to non-skiers. When reducing risk for reverse causation by excluding PD cases within the first five years from race participation, there was still a trend for lower risk of PD (HR: 0.80; 95 % CI 0.62–1.03). Further, the PD prevalence converged between skiers and non-skiers after 15 years of follow-up, which is more consistent with a motor reserve in the physically active rather than neuroprotection. Conclusions: A physical active lifestyle is associated with reduced risk for PD. This association weakens with time and might be explained by a motor reserve among the physically active.
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Keywords: Physical activity, exercise, Parkinson’s disease, motor reserve
Abstract: It is unclear whether the distribution of tau pathology differs between cases with early-onset familial Alzheimer’s disease (AD) and sporadic AD. We present positron emission tomography (PET) data from a young patient with a presenilin-1 mutation (Thr116Asn). 18 F-flutemetamol PET showed a distribution of amyloid-β fibrils similar to sporadic AD. However, the pattern of tau pathology, revealed using 18 F-AV1451 PET, showed higher uptake in posterior cingulate, precuneus, parietal and occipital cortices compared to late-onset sporadic AD. Further, the tau pathology, but not amyloid pathology, exhibited a very clear inverse relationship with 18 F-fluorodeoxyglucose-metabolism, indicating neuronal hypometabolism in regions affected…by tau aggregates.
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Keywords: Alzheimer’s disease, positron-emission tomography, presenilins, tau proteins