Health-related quality of life in Turkish patients with ankylosing spondylitis: impact of peripheral involvement on quality of life in terms of disease activity, functional status, severity of pain, and social and emotional functioning.

Ankylosing spondylitis (AS) affects sacroiliac joints at early stages and may involve the axial skeleton at later stages of disease. Peripheral involvement usually occurs in lower extremities. When it develops early in the disease course, it is a predictor of more aggressive disease. The aim of this study is to evaluate health-related quality of life (HRQoL) in AS and to assess the impact of peripheral involvement on HRQoL domains in terms of disease activity, functional status, pain, and social and emotional functioning. Seventy-four AS patients were included. Peripheral involvement was present in 51.35 % of the patients. In 65.79 % of these cases the hips, in 31.58 % the knees, in 18.42 % the shoulders and in 13.16 % the ankles were affected. Patients were evaluated by Ankylosing Spondylitis Quality of Life (ASQoL), Short Form-36 (SF-36), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Ankylosing Spondylitis Disease Activity Score (ASDAS) and Bath Ankylosing Spondylitis Functional Index (BASFI). ASQoL was strongly correlated with ASDAS, BASDAI, BASFI, and Bath Ankylosing Spondylitis Metrology Index (BASMI), severity of total pain, night pain, fatigue, morning stiffness and ESR. ASDAS and BASDAI showed the strongest correlation with ASQoL. Severity of total pain, functional status and severity of night pain followed it, respectively. Patients with peripheral involvement scored significantly lower in all subgroups of SF36 and significantly higher in ASDAS, BASDAI, BASFI, BASMI and ASQoL scores and levels of pain, night pain, fatigue and morning stiffness. Peripheral involvement is associated with more active disease and functional disability and has a negative influence on HRQoL including physical, social and emotional functioning.