title: Hypovitaminosis D and orthostatic hypotension: a systematic review and meta-analysis.
abstract: Orthostatic hypotension is a common condition among older adults and is associated with a range of deleterious outcomes. Recently, interest has developed in hypovitaminosis D (defined as low 25 hydroxiyvitamin D levels) as a potential risk factor for orthostatic hypotension. We conducted a systematic review and meta-analysis examining the association of orthostatic hypotension between study participants with and without hypovitaminosis D, including the adjustment of potential confounders (age, sex, BMI, renal function, comorbidities, seasonality, use of antihypertensive medications, and supplementation with cholecalciferol).
  
  
  
  A systematic literature search of major electronic databases from inception until 09/2015 was made for articles providing data on orthostatic hypotension and hypovitaminosis D. A random effects meta-analysis of cross-sectional studies investigating orthostatic hypotension prevalence comparing participants with vs. those without hypovitaminosis D was undertaken, calculating the odds ratios (ORs) and 95% confidence intervals (CIs).
  
  
  
  Of 317 initial hits, five cross-sectional studies were meta-analysed including 3646 participants (1270 with hypovitaminosis D and 2376 without). The participants with hypovitaminosis D had a higher prevalence of orthostatic hypotension (OR = 1.88; 95% CI: 1.25-2.84; I = 68%) that was not affected by adjusting for a median of five potential confounders (OR = 2.03; 95% CI: 1.13-3.68; I = 73%). People with orthostatic hypotension had significantly reduced serum vitamin D concentrations (standardized mean difference = -0.42; 95% CI: -0.72 to -0.12). One longitudinal study confirmed the association between hypovitaminosis D and orthostatic hypotension.
  
  
  
  Our meta-analysis highlights that hypovitaminosis D is associated with orthostatic hypotension, independent of potential confounders. Further longitudinal studies and clinical trials are required to confirm these findings.
authors.affiliation: aRheumatology Unit, Department of Medicine University of Padova, Padova, Italy bPhysiotherapy Department, South London and Maudsley NHS Foundation Trust, Denmark Hill cHealth Service and Population Research Department, Institute of Psychiatry, King's College London, De Crespigny Park, London dDepartment of Neuroscience and Memory Clinic, Division of Geriatric Medicine, Angers University Hospital; UPRES EA 4638, University of Angers, Angers, France eRobarts Research Institute, University of Western Ontario, London, Ontario, Canada fDepartment of Neurology, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung gDepartment of Neurology, Hanyang University College of Medicine, Seoul, Republic of Korea hDepartment of Gerontology, St James's Hospital, Dublin, Ireland Mercers Institute for Research on Ageing, Dublin, Ireland iDepartment of Geriatric Medicine, School of Medicine, Dokuz Eylul University, Izmir, Turkey jDepartment of Pathology and Diagnostics, Verona University and Hospital Trust, Verona kDepartment of Pathology, Santa Chiara Hospital, Trento lDepartment of Neurosciences, Local Health Unit 17, Mental Health Department, Monselice mDepartment of Medicine, Geriatrics Section, University of Padova nInstitute of Clinical Research and Education in Medicine (IREM), Padova, Italy *Francesca Ometto and Brendon Stubbs equally contributed to the writing of this article.
authors.forename: Francesca
authors.initials: F
authors.lastname: Ometto
authors.forename: Brendon
authors.initials: B
authors.lastname: Stubbs
authors.forename: Cédric
authors.initials: C
authors.lastname: Annweiler
authors.forename: Guillaume T
authors.initials: GT
authors.lastname: Duval
authors.forename: Wooyoung
authors.initials: W
authors.lastname: Jang
authors.forename: Hee-Tae
authors.initials: HT
authors.lastname: Kim
authors.forename: Kevin
authors.initials: K
authors.lastname: McCarroll
authors.forename: Conal
authors.initials: C
authors.lastname: Cunningham
authors.forename: Pinar
authors.initials: P
authors.lastname: Soysal
authors.forename: Ahmet Turan
authors.initials: AT
authors.lastname: Isik
authors.forename: Claudio
authors.initials: C
authors.lastname: Luchini
authors.forename: Marco
authors.initials: M
authors.lastname: Solmi
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Sergi
authors.forename: Enzo
authors.initials: E
authors.lastname: Manzato
authors.forename: Nicola
authors.initials: N
authors.lastname: Veronese
mesh_terms: D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D006801:Humans; D007024:Hypotension, Orthostatic / Q000097:blood / Q000453:epidemiology*; D015995:Prevalence; D012307:Risk Factors; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood / Q000453:epidemiology*
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D