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Neuroepidemiology 2011;36:150–154

Delayed Parkinson’s Disease Diagnosis among African-Americans: The Role of Reporting of Disability

Dahodwala N.a–c · Karlawish J.b, d · Siderowf A.a–c · Duda J.E.a, c · Mandell D.S.b, e
aParkinson’s Disease Research, Education and Clinical Center, Philadelphia VA Medical Center, and bLeonard Davis Institute of Health Economics and Departments of cNeurology, dMedicine and ePsychiatry, University of Pennsylvania, Philadelphia, Pa., USA
email Corresponding Author

 goto top of outline Key Words

  • African-American
  • Delay
  • Diagnosis
  • Health services
  • Parkinsonism
  • Race

 goto top of outline Abstract

Background/Aims: Racial differences in the observed prevalence of Parkinson’s disease (PD) may be due to delayed diagnosis among African-Americans. We sought to compare the stage at which African-American and white PD patients present for healthcare, and determine whether perception of disability accounts for racial differences. Methods: Using records of veterans with newly diagnosed PD at the Philadelphia Veterans Affairs Medical Center, we calculated differences in reporting of symptoms as the difference in z-scores on the Unified Parkinson Disease Rating Scale part 2 (disability) and part 3 (motor impairment). Ordinal logistic regression was used to determine predictors of stage at diagnosis. Results: African-American (n = 16) and white (n = 58) veterans with a mean age of 70.1 years were identified. African-Americans presented at a later PD stage than whites (median Hoehn + Yahr stage 2.5 vs. 2.0, p = 0.02) and were more likely to under-report disability relative to motor impairment (81 vs. 40%, p < 0.01). Multivariate analysis showed that under-reporting of disability accounted for much of the effect of race on stage of diagnosis. Conclusions: Under-reporting of disability among African-Americans may account for later stages of PD diagnosis than whites. This study begins to explain the mechanisms underlying observed racial disparities in PD.

Copyright © 2011 S. Karger AG, Basel

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 goto top of outline Author Contacts

Nabila Dahodwala, MD, MS
Parkinson’s Disease and Movement Disorders Center
330 S. 9th St., 2nd floor
Philadelphia, PA 19107 (USA)
Tel. +1 215 829 6708, E-Mail

 goto top of outline Article Information

Received: December 13, 2010
Accepted: January 29, 2011
Published online: April 20, 2011
Number of Print Pages : 5
Number of Figures : 1, Number of Tables : 1, Number of References : 21

 goto top of outline Publication Details


Vol. 36, No. 3, Year 2011 (Cover Date: June 2011)

Journal Editor: Feigin V.L. (Auckland)
ISSN: 0251-5350 (Print), eISSN: 1423-0208 (Online)

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