The natural history of juvenile-onset ankylosing spondylitis: a 24-year retrospective case-control study

One hundred and thirty-five patients with juvenile-onset ankylosing spondylitis (JAS: less than 16 years at onset, mean 12.8 years) were compared to 135 adult-onset spondylitics (AAS: greater than 21 years at onset, mean 26.1 years), controlled for disease duration (24.5 and 23.5 years, respectively), to assess the outcome of juvenile-onset disease. Review was by postal questionnaire and health-assessment measures. The sex distribution was similar: 73% and 74% males, respectively. All parameters showed comparable outcome with the exception of the numbers in full-time employment (JAS 74%, AAS 56%; p less than 0.01) and total hip replacements (JAS 17%, AAS 4%; p less than 0.01).

(a) the premature hip is particularly at risk in ankylosing spondylitis; (b) there are few differences between the outcome of JAS and AAS; (c) overall, JAS patients do well in adulthood.