title: Dementia in Parkinson's disease: Is male gender a risk factor?
abstract: The rates of cognitive decline in patients with Parkinson's disease (PD) are higher than in the general population. Age and disease duration have been associated with increasing rates of dementia in PD. However, the role of other factors including gender has been poorly investigated. We investigated the relationship between dementia and gender along with other established risk factors, such as age and disease duration.
  
  
  
  We conducted a cross-sectional retrospective study including all consecutive patients diagnosed with idiopathic PD attending a single out-patient tertiary clinic over an 18-year period (1995-2013). Dementia was diagnosed according to DSM-IV criteria.
  
  
  
  Prevalence of dementia was 11.5% (95%CI, 10.8-12.3) and 13.5% (95%CI, 12.7-14.5) in the whole population (N = 6599) and in those aged ≥60 years (N = 5373), respectively. Age and disease duration were independently associated with dementia, and the latter was associated with dementia up to 84 years of age. Male gender was an independent risk factor. In addition, while the rate of dementia increased in males over all age strata, we found that in females prevalence began to increase steadily after the age of 65 years, reaching male estimates only after 80 years of age. Higher rates in male gender were observed between 60 and 80 years of age.
  
  
  
  Age and PD duration are confirmed risk factors for dementia. However, disease duration appeared to be a less important factor in cognitive decline in patients aged ≥85 years. As opposed to gender-specific estimates in the general population, male gender is likely associated with higher rates of dementia in PD patients.
authors.affiliation: Nutrition and Dietetics Service, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy. Electronic address: e.cereda@smatteo.pv.it.
authors.forename: Emanuele
authors.initials: E
authors.lastname: Cereda
authors.affiliation: Parkinson Institute, ASST G.Pini - CTO, ex ICP, Milano, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Cilia
authors.affiliation: Biometry and Statistics Service, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
authors.forename: Catherine
authors.initials: C
authors.lastname: Klersy
authors.affiliation: Parkinson Institute, ASST G.Pini - CTO, ex ICP, Milano, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Siri
authors.affiliation: Parkinson Institute, ASST G.Pini - CTO, ex ICP, Milano, Italy.
authors.forename: Beatrice
authors.initials: B
authors.lastname: Pozzi
authors.affiliation: Parkinson Institute, ASST G.Pini - CTO, ex ICP, Milano, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Reali
authors.affiliation: Parkinson Institute, ASST G.Pini - CTO, ex ICP, Milano, Italy.
authors.forename: Aurora
authors.initials: A
authors.lastname: Colombo
authors.affiliation: Parkinson Institute, ASST G.Pini - CTO, ex ICP, Milano, Italy.
authors.forename: Anna Lena
authors.initials: AL
authors.lastname: Zecchinelli
authors.affiliation: Parkinson Institute, ASST G.Pini - CTO, ex ICP, Milano, Italy.
authors.forename: Claudio Bruno
authors.initials: CB
authors.lastname: Mariani
authors.affiliation: Parkinson Institute, ASST G.Pini - CTO, ex ICP, Milano, Italy.
authors.forename: Silvana
authors.initials: S
authors.lastname: Tesei
authors.affiliation: Parkinson Institute, ASST G.Pini - CTO, ex ICP, Milano, Italy.
authors.forename: Margherita
authors.initials: M
authors.lastname: Canesi
authors.affiliation: Parkinson Institute, ASST G.Pini - CTO, ex ICP, Milano, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Sacilotto
authors.affiliation: Parkinson Institute, ASST G.Pini - CTO, ex ICP, Milano, Italy.
authors.forename: Nicoletta
authors.initials: N
authors.lastname: Meucci
authors.affiliation: Parkinson Institute, ASST G.Pini - CTO, ex ICP, Milano, Italy.
authors.forename: Michela
authors.initials: M
authors.lastname: Zini
authors.affiliation: Parkinson Institute, ASST G.Pini - CTO, ex ICP, Milano, Italy.
authors.forename: Ioannis Ugo
authors.initials: IU
authors.lastname: Isaias
authors.affiliation: Parkinson Institute, ASST G.Pini - CTO, ex ICP, Milano, Italy.
authors.forename: Michela
authors.initials: M
authors.lastname: Barichella
authors.affiliation: Parkinson Institute, ASST G.Pini - CTO, ex ICP, Milano, Italy.
authors.forename: Erica
authors.initials: E
authors.lastname: Cassani
authors.affiliation: Parkinson Institute, ASST G.Pini - CTO, ex ICP, Milano, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Goldwurm
authors.affiliation: Parkinson Institute, ASST G.Pini - CTO, ex ICP, Milano, Italy.
authors.forename: Gianni
authors.initials: G
authors.lastname: Pezzoli
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D003704:Dementia / Q000175:diagnosis* / Q000453:epidemiology* / Q000523:psychology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000175:diagnosis* / Q000453:epidemiology* / Q000523:psychology; D012189:Retrospective Studies; D012307:Risk Factors; D012727:Sex Characteristics
keywords: Dementia; Epidemiology; Gender; Parkinson's disease; Prevalence