title: Anxiety in Parkinson's disease: Symptom dimensions and overlap with depression and autonomic failure.
abstract: BACKGROUND
  Anxiety disorders are highly prevalent in patients with Parkinson's disease (PD) and have a major impact on wellbeing. They nevertheless receive limited scientific attention. This study aimed to establish the symptom dimensions of anxiety in PD, and their relationship with depression, autonomic failure and motor symptoms.
  
  
  METHODS
  In this cross-sectional observational study, symptoms of anxiety were measured with the Beck Anxiety Inventory (BAI) in 294 PD patients. Symptom dimensions of anxiety in PD were explored through principal component analysis (PCA) of BAI items. The relationship between anxiety and depressive, autonomic and motor symptoms was assessed through PCA and regression analyses.
  
  
  RESULTS
  Clinically relevant symptoms of anxiety were present in 45% of patients. PCA of the BAI resulted in five subscales, corresponding to a single affective and four somatic symptom dimensions (thermoregulation, hypotension, hyperventilation and trembling) of anxiety. Symptoms of anxiety and depression displayed a large overlap. All somatic BAI subscales were significantly influenced by motor and autonomic symptoms, while the affective subscale was not.
  
  
  CONCLUSIONS
  Anxiety in PD comprises affective and somatic symptom dimensions. The affective subscale of the BAI is not influenced by motor or autonomic symptoms, and may therefore prove useful for future research. Scores on the somatic subscales of the BAI were associated with autonomic failure and motor impairment, demonstrating a strong interplay between motor and non-motor symptoms in PD. These results stress the importance of a holistic approach of anxiety in PD.
authors.affiliation: Department of Psychiatry, VU University Medical Centre, Amsterdam, The Netherlands; Department of Anatomy & Neurosciences, VU University Medical Centre, Amsterdam, The Netherlands; EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands. Electronic address: s.rutten@vumc.nl.
authors.forename: Sonja
authors.initials: S
authors.lastname: Rutten
authors.affiliation: Department of Psychiatry, VU University Medical Centre, Amsterdam, The Netherlands.
authors.forename: Ires
authors.initials: I
authors.lastname: Ghielen
authors.affiliation: Department of Psychiatry, VU University Medical Centre, Amsterdam, The Netherlands; Department of Anatomy & Neurosciences, VU University Medical Centre, Amsterdam, The Netherlands; Neuroscience Campus Amsterdam, VU University Medical Centre, Amsterdam, The Netherlands; Department of Neurology, VU University Medical Centre, Amsterdam, The Netherlands.
authors.forename: Chris
authors.initials: C
authors.lastname: Vriend
authors.affiliation: Department of Psychiatry, VU University Medical Centre, Amsterdam, The Netherlands.
authors.forename: Adriaan W
authors.initials: AW
authors.lastname: Hoogendoorn
authors.affiliation: Neuroscience Campus Amsterdam, VU University Medical Centre, Amsterdam, The Netherlands; Department of Neurology, VU University Medical Centre, Amsterdam, The Netherlands.
authors.forename: Henk W
authors.initials: HW
authors.lastname: Berendse
authors.affiliation: Department of Psychiatry, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: Albert F G
authors.initials: AF
authors.lastname: Leentjens
authors.affiliation: Department of Anatomy & Neurosciences, VU University Medical Centre, Amsterdam, The Netherlands; Neuroscience Campus Amsterdam, VU University Medical Centre, Amsterdam, The Netherlands; Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, The Netherlands.
authors.forename: Ysbrand D
authors.initials: YD
authors.lastname: van der Werf
authors.affiliation: Department of Psychiatry, VU University Medical Centre, Amsterdam, The Netherlands; EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Jan H
authors.initials: JH
authors.lastname: Smit
authors.affiliation: Department of Psychiatry, VU University Medical Centre, Amsterdam, The Netherlands; Department of Anatomy & Neurosciences, VU University Medical Centre, Amsterdam, The Netherlands; Neuroscience Campus Amsterdam, VU University Medical Centre, Amsterdam, The Netherlands.
authors.forename: Odile A
authors.initials: OA
authors.lastname: van den Heuvel
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001007:Anxiety / Q000209:etiology*; D001342:Autonomic Nervous System Diseases / Q000175:diagnosis / Q000209:etiology*; D003430:Cross-Sectional Studies; D003863:Depression / Q000175:diagnosis / Q000209:etiology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D019370:Observation; D010300:Parkinson Disease / Q000150:complications*; D025341:Principal Component Analysis; D011569:Psychiatric Status Rating Scales; D015899:Tomography, Emission-Computed, Single-Photon
keywords: Anxiety; Beck Anxiety Inventory; Depression; Factor analysis; Parkinson's disease