title: Relationship between vitamin D and lung function, physical performance and balance on patients with stage I-III chronic obstructive pulmonary disease.
abstract: OBJECTIVE
  vitamin D is important for muscle function and it affects different aspects of muscle metabolism. This study aim to determine whether serum 25(OH) D levels are related to lung functions, physical performance and balance in patients with chronic obstructive pulmonary disease (COPD).
  
  
  METHODS
  in 90 patients with COPD and 57 healthy controls lung function tests, physical performance tests (time up and go, gait velocity test, sit-to-stand test, isometric strength, isokinetic strength), static (functional reach test) and dynamic (time up and go) balance tests and the association of 25(OH)D levels with lung functions, physical performance and balance were evaluated.
  
  
  RESULTS
  the COPD patients had significantly more deﬁcit in physical function and balance parameters, and in dynamic balance test (p<0.005). Isokinetic knee muscle strength (flexor and extensor) in COPD patients was significantly lower than in the controls (p<0.05); FEV1 (p=0.008), FVC (p=0.02), FEV1/FVC (p=0.04), TLC (p=0.01) were lower in COPD patients with vitamin D deficiency [25(OH) D less than 15 ng/mL] than in COPD patients without vitamin D deficiency. Hand grip test (p=0.000) and isokinetic knee muscle strength (flexor and extensor) (p<0.05) were also lower in COPD patients with vitamin D deficiency. Vitamin D deficiency was more pronounced in patients with stage III COPD (p<0.05).
  
  
  CONCLUSIONS
  patients with COPD had worst physical functioning, poor balance and less muscle strength. Severe disturbed lung and peripheral muscle functions are more pronounced in COPD patients with vitamin D deficiency.
authors.affiliation: Department of Chest Diseases, Inonu University, Malatya, Turkey.
authors.forename: Tuncay
authors.initials: T
authors.lastname: Yumrutepe
authors.affiliation: Department of Chest Diseases, Inonu University, Malatya, Turkey.
authors.forename: Zeynep Ayfer
authors.initials: ZA
authors.lastname: Aytemur
authors.affiliation: Department of Physical Medicine and Rehabilitation, Inonu University, Malatya, Turkey.
authors.forename: Ozlem
authors.initials: O
authors.lastname: Baysal
authors.affiliation: Department of Nephrology, Inonu University, Malatya, Turkey.
authors.forename: Hulya
authors.initials: H
authors.lastname: Taskapan
authors.affiliation: Department of Biochemistry, Inonu University, Malatya, Turkey.
authors.forename: Cagatay M
authors.initials: CM
authors.lastname: Taskapan
authors.affiliation: Department of Chest Diseases, Inonu University, Malatya, Turkey.
authors.forename: Suleyman Savas
authors.initials: SS
authors.lastname: Hacievliyagil
mesh_terms: D015652:25-Hydroxyvitamin D 2 / Q000097:blood*; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007717:Knee / Q000502:physiology; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D053580:Muscle Strength / Q000502:physiology; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood / Q000503:physiopathology*; D012720:Severity of Illness Index; D014808:Vitamin D Deficiency / Q000503:physiopathology*
chemical_list: D015652:25-Hydroxyvitamin D 2