Predicting persistent inflammatory arthritis amongst early arthritis clinic patients in the UK: is musculoskeletal ultrasound required?

INTRODUCTION: Analyses of large clinical datasets from early arthritis cohorts permit the development of algorithms that may be used for outcome prediction in individual patients. The value added by routine use of musculoskeletal ultrasound (MSUS) in an early arthritis setting, as a component of such predictive algorithms, remains to be determined. METHODS: The authors undertook a retrospective analysis of a large, true-to-life, observational inception cohort of early arthritis patients in Newcastle upon Tyne, UK, which included patients with inflammatory arthralgia but no clinically swollen joints. A pragmatic, 10-minute MSUS assessment protocol was developed, and applied to each of these patients at baseline. Logistic regression was used to develop two "risk metrics" that predicted the development of a persistent inflammatory arthritis (PIA), with or without the inclusion of MSUS parameters. RESULTS: A total of 379 enrolled patients were assigned definitive diagnoses after ≥12 months follow-up (median 28 months), of whom 162 (42%) developed a persistent inflammatory arthritis. A risk metric derived from 12 baseline clinical and serological parameters alone had an excellent discriminatory utility with respect to an outcome of PIA (area under receiver operator characteristic (ROC) curve 0.91; 95% CI 0.88 to 0.94). The discriminatory utility of a similar metric, which incorporated MSUS parameters, was not significantly superior (area under ROC curve 0.91; 95% CI 0.89 to 0.94). Neither did this approach identify an added value of MSUS over the use of routine clinical parameters in an algorithm for discriminating PIA patients whose outcome diagnosis was rheumatoid arthritis (RA). CONCLUSIONS: MSUS use as a routine component of assessment in an early arthritis clinic did not add substantial discriminatory value to a risk metric for predicting PIA.

Causes of death in patients with rheumatoid arthritis: comparison with siblings and matched osteoarthritis controls.

OBJECTIVE: Survival of patients with rheumatoid arthritis (RA) is reduced when compared to the general population. We assessed differences in causes and age of death between patients with RA and their siblings. Comparisons were also made with a control group of subjects with lower limb osteoarthritis (OA). METHODS: A population of 257 patients with RA studied in 1991 was compared to 371 of their same-sex siblings and 485 patients with hip and knee OA who were also attending the department at this time. Death certificates were obtained and compared. RESULTS: Among patients with RA, 54% (139/257) were deceased, compared to 28% (105/371) of the siblings and 32% (154/485) of OA patients (RA vs siblings or OA, p < 0.05). There were more deaths due to ischemic heart disease (IHD) in both the RA and OA groups compared to those expected; ratio observed/expected, 1.66 (95% CI 1.01, 2.79) and 1.96 (95% CI 1.21, 3.25), respectively, but not for siblings: observed/expected = 1.05 (95% CI 0.53, 2.08). There was a significant deficit in cancer related deaths in RA patients, observed/expected = 0.62 (95% CI 0.36, 1.03). CONCLUSION: Significantly more patients with RA had died than in either of the comparator populations. RA and OA patients died more frequently of IHD than the siblings. The RA population had a 40% reduced rate of cancer related deaths than expected and compared to their siblings.