Geographic and Ethnic Variation in Parkinson Disease: A Population-Based Study of US Medicare Beneficiaries

Department of Neurology, Washington University School of Medicine, 660 South Euclid Avenue, Campus Box 8111, St. Louis, MO 63110, USA.
Neuroepidemiology (Impact Factor: 2.48). 01/2010; 34(3):143-51. DOI: 10.1159/000275491
Source: PubMed

ABSTRACT Parkinson disease is a common neurodegenerative disease. The racial, sex, age, and geographic distributions of Parkinson disease in the US are unknown.
We performed a serial cross-sectional study of US Medicare beneficiaries aged 65 and older from the years 1995, and 2000-2005. Using over 450,000 Parkinson disease cases per year, we calculated Parkinson disease prevalence and annual incidence by race, age, sex, and county. Spatial analysis investigated the geographic distribution of Parkinson disease.
Age-standardized Parkinson disease prevalence (per 100,000) was 2,168.18 (+/-95.64) in White men, but 1,036.41 (+/-86.01) in Blacks, and 1,138.56 (+/-46.47) in Asians. The incidence ratio in Blacks as compared to Whites (0.74; 95% CI = 0.732-0.748) was higher than the prevalence ratio (0.58; 95% CI = 0.575-0.581), whereas the incidence ratio for Asians (0.69; 95% CI = 0.657-0.723) was similar to the prevalence ratio (0.62; 95% CI = 0.617-0.631). Bayesian mapping of Parkinson disease revealed a concentration in the Midwest and Northeast regions. Mean county incidence by quartile ranged from 279 to 3,111, and prevalence from 1,175 to 13,800 (per 100,000). Prevalence and incidence in urban counties were greater than in rural ones (p < 0.01). Cluster analysis supported a nonrandom distribution of both incident and prevalent Parkinson disease cases (p < 0.001).
Parkinson disease is substantially more common in Whites, and is nonrandomly distributed in the Midwest and Northeastern US.

Download full-text


Available from: Brad A Racette, Jul 06, 2015
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Parkinson’s disease (PD) is characterized by dopaminergic (DA) neuron depletion. Early detection of PD may help in selecting the appropriate treatment. Biomarkers of PD have been suggested, however none of these is currently in clinical use. The aim of this study was to identify volatile organic compounds (VOCs) as early biomarkers of PD. Our hypothesis was that during PD progression, specific VOCs are generated that are linked to the biochemical pathways characterizing PD. These VOCs can be detected by GC–MS combined with solid-phase microextraction (SPME) technique. Three groups of rats were studied: DA-lesioned rats injected with 6-hydroxydopamine (HDA; 250 μg/rat n=11); control rats injected with saline (n=9), and control rats injected with DSP-4 (n=8), a specific noradrenergic neuron toxin. Blood and striatal tissue homogenate were analyzed. In the blood, 1-octen-3-ol and 2-ethylhexanol were found at significantly higher concentrations in HDA versus sham rats. In the striatal homogenate 1-octen-3-ol and other four compounds were found at significantly lower concentrations in HDA versus sham rats. 1-Octen-3-ol is a cytotoxic compound. These results may lead to the development of an early diagnostic test for PD based on profiling of VOCs in body fluids.
    Neurochemistry International 10/2014; DOI:10.1016/j.neuint.2014.06.016 · 2.65 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: PURPOSE: We examined the prevalence and risk of clinical symptoms in a large number of Japanese patients with Parkinson's disease (PD) (n = 1453; 650 males). METHODS: Events were analyzed using Kaplan-Meier survival curves, logistic regression, and Cox proportional-hazards models. RESULTS: The mean age (SD) was 67.7 (10.0), age of onset was 58.0 (11.5), and disease duration was 9.7 (6.6) years. The mean modified Hoehn and Yahr stage was 2.8 (1.2). Most patients (88.9%) received levodopa (547.7 (257.6) mg/day). A large proportion (81.3%) received dopamine agonists (136.2 (140.7) mg/day). About 23.4% received pain treatment 6.9 (5.1) years after the onset; females (p < 0.05) and patients with late-onset PD (≥60 years, p < 0.001) were more likely to be affected. About 44.7% of patients had wearing-off 7.5 (4.7) years after the onset, and it was more common in females (p < 0.001) and patients with early-onset PD (p < 0.001). Camptocormia was found in 9.5% of patients 8.1 (6.2) years after the onset, and it was more common in females (p < 0.05) and patients with late-onset PD (p < 0.05). About 28.6% of patients developed psychosis 9.0 (5.4) years after the onset, and it was more likely to occur in patients with late-onset PD (p < 0.001). Late-onset PD and cerebrovascular disease were also associated with increased risk of pneumonia. CONCLUSIONS: Considering that very few studies have assessed numerous clinical symptoms in the same report, these data provide a useful reference for the clinical course of PD.
    Parkinsonism & Related Disorders 04/2013; 19(8). DOI:10.1016/j.parkreldis.2013.04.001 · 4.13 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: This study explores the effect of continuous exposure to bright light on neuromelanin formation and dopamine neuron survival in the substantia nigra. Twenty-one days after birth, Sprague–Dawley albino rats were divided into groups and raised under different conditions of light exposure. At the end of the irradiation period, rats were sacrificed and assayed for neuromelanin formation and number of TH-positive neurons in the substantia nigra. The rats exposed to bright light for 20 days or 90 days showed a relatively greater number of neuromelanin-positive neurons. Surprisingly, tyrosine hydroxylase-positive neurons decreased progressively in the substantia nigra reaching a significant 29% reduction after 90 days of continuous bright light exposure. This decrease was paralleled by a diminution of dopamine and its metabolite in the striatum. Remarkably, in preliminary analysis that accounted for population density, the age and race adjusted Parkinson's disease prevalence significantly correlated with average satellite observed sky light pollution.
    Scientific Reports 03/2013; 3. DOI:10.1038/srep01395 · 5.58 Impact Factor