title: Comorbid conditions associated with Parkinson's disease: A longitudinal and comparative study with Alzheimer disease and control subjects.
abstract: OBJECTIVE
  To study what comorbid conditions were present at baseline and 3years later in a cohort of Spanish Parkinson's disease (PD) patients, to compare comorbidity with both Alzheimer's disease (AD) and control groups and to analyze the role of comorbidity as predictor of mortality.
  
  
  METHODS
  One hundred and forty-seven non-demented PD patients (57.1% males; 70.9±8.6years old) were included in this 36months follow-up (2012-2015), monocenter, evaluation study. The International Classification of Diseases, Tenth Revision (ICD-10), Charlson Index (CI), Comorbidity-Polypharmacy Score (CPS) and Elixhauser Comorbidity Measure (ECM) were used to assess comorbidity at baseline and at 3years. Forty-four AD patients and 44 control subjects were included as comparator groups.
  
  
  RESULTS
  Total number of comorbidities (ICD-10) and polypharmacy at baseline were higher in PD and AD patients than controls (4.4±2.3 vs 5.2±2.4 vs 3.4±1.9 [p=0.001] and 81.6% vs 75% vs 56.8% [p=0.003], respectively). Diseases of the circulatory system (ICD-10/chapter-IX) and endocrine, nutritional and metabolic diseases (ICD-10/chapter-IV) were the most frequent in all groups. There was a significant increase in comorbidity (mean, +1.6±2.8) in all groups (p<0.0001) without differences between them. Seventeen patients died and 8 cases were did not follow-up. Comorbidity was a predictor of death in PD patients after adjust for other covariates (including age, sex, disease duration, disease stage, motor status and non-motor symptoms): ICD-10 (total number of comorbidities), hazard ratio 1.285 (95% confidence interval, 1.047-1.577; p=0.017); CI, hazard ratio 1.462 (95% confidence interval, 1.045-2.047; p=0.027).
  
  
  CONCLUSIONS
  Comorbidity is frequent in PD patients, increases significantly over time and predicts mortality.
authors.affiliation: Section of Neurology, Complejo Hospitalario Universitario de Ferrol (CHUF), Hospital A. Marcide, Ferrol, A Coruña, Spain. Electronic address: diegosangar@yahoo.es.
authors.forename: D
authors.initials: D
authors.lastname: Santos García
authors.affiliation: Section of Neurology, Complejo Hospitalario Universitario de Ferrol (CHUF), Hospital A. Marcide, Ferrol, A Coruña, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Suárez Castro
authors.affiliation: Section of Neurology, Complejo Hospitalario Universitario de Ferrol (CHUF), Hospital A. Marcide, Ferrol, A Coruña, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Expósito
authors.affiliation: Section of Neurology, Complejo Hospitalario Universitario de Ferrol (CHUF), Hospital A. Marcide, Ferrol, A Coruña, Spain.
authors.forename: T
authors.initials: T
authors.lastname: de Deus
authors.affiliation: Section of Neurology, Complejo Hospitalario Universitario de Ferrol (CHUF), Hospital A. Marcide, Ferrol, A Coruña, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Tuñas
authors.affiliation: Section of Neurology, Complejo Hospitalario Universitario de Ferrol (CHUF), Hospital A. Marcide, Ferrol, A Coruña, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Aneiros
authors.affiliation: Section of Neurology, Complejo Hospitalario Universitario de Ferrol (CHUF), Hospital A. Marcide, Ferrol, A Coruña, Spain.
authors.forename: M
authors.initials: M
authors.lastname: López Fernández
authors.affiliation: Department of Psychiatry, Complejo Hospitalario Universitario de Ferrol (CHUF), Hospital Naval, Ferrol, A Coruña, Spain.
authors.forename: D
authors.initials: D
authors.lastname: Núñez Arias
authors.affiliation: Department of Family Medicine, Complejo Hospitalario Universitario de Ferrol (CHUF), Ferrol, A Coruña, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Bermúdez Torres
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000188:drug therapy / Q000453:epidemiology*; D015897:Comorbidity; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009017:Morbidity; D010300:Parkinson Disease / Q000188:drug therapy / Q000453:epidemiology*; D019338:Polypharmacy; D011379:Prognosis; D012189:Retrospective Studies; D013030:Spain / Q000453:epidemiology
keywords: Age; Alzheimer disease; Comorbidity; Mortality; Motor complications; Parkinson's disease; Polypharmacy