title: Respiratory muscle strength but not BASFI score relates to diminished chest expansion in ankylosing spondylitis.
abstract: Pulmonary function is altered in ankylosing spondylitis (AS) owing mainly to the restriction of chest wall involvement (limited chest expansion). The objective of this study was to investigate the relationship between chest expansion, respiratory muscle strength (MIP, MEP) maximum voluntary ventilation (MVV), and BASFI score in patients with AS. Twenty-three male patients with definite AS and 21 age-matched healthy male controls were recruited for the study. Patients with AS were assessed for functional status by BASFI. Measurement of chest expansion and lumbar spinal flexion (modified Schober) method was performed in all subjects. Pulmonary function tests were performed by spirometry. Respiratory muscle strength was evaluated by a mouth-pressure meter (MPM). Body mass index (kg/m(2)) was recorded in all individuals. Chest expansion and modified Schober measurement were significantly lower in AS patients (p<0.05). Pulmonary function tests revealed restrictive lung disease. The mean BASFI score suggested good functional capacity in the AS group. The respiratory muscle strength and MVV were also lower in AS (p<0.05). The chest expansion was correlated with MIP and MEP values (r=0.491; p=0.02, r=0.436; p=0.05). Chest expansion was also correlated negatively with disease duration (r=-0.502; p=0.03). In addition, there was no correlation between chest expansion and BASFI score (r=-0.076; p=0.773). This study demonstrates that functional status (BASFI) is not influenced by the limitation of chest wall movement. It may be as a result of the maintenance of moderate physical activity during active life in patients with AS.
authors.affiliation: Faculty of Medicine, Department of Physical Medicine and Rehabilitation, Mersin University, Fatih Mah.13 Sokak, Istanbul Evleri, C blok kat1/1, Mezitli, Mersin, Turkey. gunsahsahin@hotmail.com
authors.forename: Günşah
authors.initials: G
authors.lastname: Sahin
authors.forename: Mukadder
authors.initials: M
authors.lastname: Calikoğlu
authors.forename: Cengiz
authors.initials: C
authors.lastname: Ozge
authors.forename: Nurgul
authors.initials: N
authors.lastname: Incel
authors.forename: Ali
authors.initials: A
authors.lastname: Biçer
authors.forename: Bahar
authors.initials: B
authors.lastname: Ulşubaş
authors.forename: Hayal
authors.initials: H
authors.lastname: Güler
mesh_terms: D006305:Health Status Indicators; D006801:Humans; D008171:Lung Diseases / Q000209:etiology / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D012123:Pulmonary Ventilation / Q000502:physiology; D012129:Respiratory Function Tests; D015656:Respiratory Mechanics / Q000502:physiology*; D012132:Respiratory Muscles / Q000503:physiopathology*; D013167:Spondylitis, Ankylosing / Q000150:complications*; D035441:Thoracic Wall / Q000503:physiopathology*