title: Quality of life and Parkinson's disease.
abstract: BACKGROUND
  People with Parkinson's disease (PD) have a progressive loss of function eventually leading to severe disability. Although PD would be expected to have a profound impact on an individual's psychosocial health, there is relatively limited research on its psychosocial effect. The purposes of this study were (a) to examine the relationships between physical disability, depression, and control beliefs and quality of life in people with PD and (b) to characterize how these psychosocial variables differ by stage of disease.
  
  
  METHODS
  Eighty-six individuals from five stages based on clinical disability, ages 51-87, were interviewed. Established instruments were used to measure physical disability, depression, and control beliefs. Quality of life (QOL) was rated on a 5-point Likert scale.
  
  
  RESULTS
  A multivariable regression model including physical disability, stage of disease, depression, mastery, and health locus of control predicted QOL (R2 = 0.48), with mastery as the only significant predictor (p = .0001). There were significant differences by PD stage for all variables (p < .05).
  
  
  CONCLUSIONS
  Mastery predicted quality of life in individuals with PD even when depression and physical disability were included in the model. Differences in psychosocial variables by stage of PD suggest that the psychosocial profile of PD patients may change as the disease progresses.
authors.affiliation: Carolinas Medical Center, Charlotte, North Carolina, USA.
authors.forename: P A
authors.initials: PA
authors.lastname: Koplas
authors.forename: H B
authors.initials: HB
authors.lastname: Gans
authors.forename: M P
authors.initials: MP
authors.lastname: Wisely
authors.forename: M
authors.initials: M
authors.lastname: Kuchibhatla
authors.forename: T M
authors.initials: TM
authors.lastname: Cutson
authors.forename: D T
authors.initials: DT
authors.lastname: Gold
authors.forename: C T
authors.initials: CT
authors.lastname: Taylor
authors.forename: M
authors.initials: M
authors.lastname: Schenkman
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D001294:Attitude to Health; D003430:Cross-Sectional Studies; D003863:Depression / Q000523:psychology; D006233:Persons with Disabilities; D018450:Disease Progression; D005260:Female; D005544:Forecasting; D006801:Humans; D007389:Internal-External Control; D008297:Male; D008875:Middle Aged; D009048:Motor Skills / Q000502:physiology; D015999:Multivariate Analysis; D010300:Parkinson Disease / Q000145:classification / Q000503:physiopathology / Q000523:psychology*; D011788:Quality of Life; D012044:Regression Analysis; D012917:Social Adjustment