Ankylosing spondylitis: how diagnostic and therapeutic delay have changed over the last six decades

Ankylosing spondylitis (AS) is a chronic, progressive, and disabling disease, but the diagnosis is often missed and markedly delayed. An early diagnosis is important to establish a treatment to reduce disability and modify the natural course of disease. The aim of this study was to investigate the diagnostic (DD) and therapeutic (TD) delay according to the decade of diagnosis. The DD and TD correlation with radiological severity score and the new imaging techniques used in diagnosis (magnetic resonance [MRI], computerised tomography, scintigraphy for sacroiliac joints) were also investigated.

135 AS patients (45 female and 90 male, 36.5±10.2 years old at diagnosis) with disease onset between 1950 and 2008, were investigated; the time from onset to diagnosis (DD) and treatment (TD), the New York and ASAS criteria fulfilment, the New York sacroiliac radiological score, bamboo spine presence at first visit and the new imaging technique used at diagnosis were recorded and their correlations were analysed.

The New York and ASAS criteria were met at the first visit, by 87% and 96%, respectively. The delay from onset of symptoms to diagnosis and treatment was 9±8 and 12±11 years, respectively, but decreased significantly between different decades (p<0.001). The severity of sacroiliitis (mean 2±1; 17/135, 12.5% - IV grade sacroiliitis at diagnosis) and bamboo spine (3.7% at diagnosis) correlated with DD and TD (p<0.001). Sacroiliac MRI use at diagnosis significantly decreased both DD and TD (p>0.001 and p<0.05, respectively).

DD and TD were correlated to radiological severity; they progressively decreased over 6 decades.