Survival of cancer in patients with rheumatoid arthritis: a follow-up study in Sweden of patients hospitalized with rheumatoid arthritis 1 year before diagnosis of cancer

Methods. RA patients were identified from the Swedish Hospital Discharge Register by linkage to the Cancer Registry. Follow-up of patients was started from the date of diagnosis of cancer through year 2006. Hazard ratios (HRs) were calculated in cancer patients with RA compared with subjects without RA. Results. A total of 1 411 163 cancer patients were identified in the database, of whom 6309 had a previous hospitalization for RA. Compared with all cancer patients without RA, patients with RA had a worse prognosis, with an HR of 1.29 and 1.31 for cause-specific and overall survival, respectively. For specific cancer sites, skin and breast cancers and non-Hodgkin's lymphoma showed worst survival. Age stratification did not change the results. Conclusion. Cancer patients with a previous hospitalization for RA had a worse prognosis for all and many site-specific cancers compared with patients without RA, independent of age at diagnosis and tumour staging. Improvement of survival for cancer patients with RA may require a multidisciplinary approach to accommodate the comorbidity.