Background/Purpose: Data on disease characteristics of geriatric patients (>=65 years) with AS are lacking. The objective of this study is to compare: 1) the clinical profile of geriatric and non-geriatric patients with AS and 2) geriatric AS patients with aged-matched non-AS comparators.

Methods: Data were extracted from a Toronto based longitudinal SpA cohort. Patients with AS were divided by current age into geriatric (age >= 65 years) and non-geriatric (age < 65 years) groups. Clinical and laboratory data were then compared. Data for the non-AS geriatric age-matched control group was obtained from a Toronto tertiary care orthopedics clinic.

Results: There were 48 geriatric AS patients out of 890 AS patients in the clinic (table 1). 322 knee OA patients were included for the non-AS geriatric comparison (table 2). Initial comparison (young vs geriatric AS), showed no differences in sex distribution. Age at time of diagnosis was higher in the geriatric AS patients (p<0.001). In terms of clinical activity, there was no difference in mean inflammatory markers or BASDAI scores. Extra-articular manifestations were similar. There was no significant difference between the 2 groups regarding the usage of NSAIDs, DMARDS, corticosteroids and biologics, nor in their side-effects. Only 1% of the geriatric group started biologic therapy at age >=65 yr. Infection frequency was similar between the two groups. Mobility (BASMI) and function (BASFI) scores were higher in the geriatric group (p<0.001 and 0.04 respectively). The geriatric group were more likely to have a history of physical trauma/ injury (p=0.03). The SF-36 mental component was also higher in the geriatric group. Quality of life scores were similar. Comparison of geriatric AS and geriatric OA patients revealed more males in the AS group. Non-AS patients are more likely to be smokers and have a history of diabetes (p=0.04). Functional disability scores were also higher.

Conclusion: We show that geriatric AS patients have reassuringly similar treatment and disease activity parameters, but differed in a select few functional components and comorbidities when compared to the younger population. The younger population was diagnosed earlier than the elder group, which may reflect better disease awareness among physicians over the last few years. When compared to geriatric non-AS controls, there was a higher prevalence of females, diabetes and smokers in the non-AS geriatric patients. Further research into the geriatric AS population is needed to better define and manage their specific needs, especially as this patient population will be substantial in the coming years.