Nils Feltelius

Haematopoietic malignancies in rheumatoid arthritis: lymphoma risk and characteristics after exposure to tumour necrosis factor antagonists

Background: Patients with rheumatoid arthritis (RA) are at increased risk of malignant lymphomas, and maybe also of leukaemia and multiple myeloma. The effect of tumour necrosis factor (TNF) antagonists on lymphoma risk and characteristics is unclear. Objective: To assess expected rates and relative risks of haematopoietic malignancies, especially those associated with TNF antagonists, in large population based cohorts of patients with RA. Methods: A population based cohort study was performed of patients with RA (one prevalent cohort (nu200a=u200a53 067), one incident cohort (nu200a=u200a3703), and one TNF antagonist treated cohort 1999 through 2003 (nu200a=u200a4160)), who were linked with the Swedish Cancer Register. Additionally, the lymphoma specimens for the 12 lymphomas occurring in patients with RA exposed to TNF antagonists in Sweden 1999 through 2004 were reviewed. Results: Study of almost 500 observed haematopoietic malignancies showed that prevalent and incident patients with RA were at increased risk of lymphoma (SIRu200a=u200a1.9 and 2.0, respectively) and leukaemia (SIRu200a=u200a2.1 and 2.2, respectively) but not of myeloma. Patients with RA treated with TNF antagonists had a tripled lymphoma risk (SIRu200a=u200a2.9) compared with the general population. After adjustment for sex, age, and disease duration, the lymphoma risk after exposure to TNF antagonists was no higher than in the other RA cohorts. Lymphomas associated with TNF antagonists had characteristics similar to those of other RA lymphomas. Conclusion: Overall, patients with RA are at equally increased risks for lymphomas and leukaemias. Patients with RA treated with TNF antagonists did not have higher lymphoma risks than other patients with RA. Prolonged observation is needed to determine the long term effects of TNF antagonists on lymphoma risk.

Disease activity and risk of lymphoma in patients with rheumatoid arthritis: nested case-control study

Disease activity and risk of lymphoma in patients with rheumatoid arthritis: nested case-control study

Risks of solid cancers in patients with rheumatoid arthritis and after treatment with tumour necrosis factor antagonists

Background: Existing studies of solid cancers in rheumatoid arthritis (RA) reflect cancer morbidity up until the early 1990s in prevalent cohorts admitted to hospital during the 1980s. Objective: To depict the cancer pattern of contemporary patients with RA, from updated risk data from prevalent and incident RA populations. To understand the risk of solid cancer after tumour necrosis factor (TNF) treatment by obtaining cancer data from cohorts treated in routine care rather than trials. Methods: A population based study of three RA cohorts (one prevalent, admitted to hospital 1990–2003 (nu200a=u200a53 067), one incident, diagnosed 1995–2003 (nu200a=u200a3703), and one treated with TNF antagonists 1999–2003 (nu200a=u200a4160)), which were linked with Swedish nationwide cancer and census registers and followed up for cancer occurrence through 2003. Results: With 3379 observed cancers, the prevalent RA cohort was at marginally increased overall risk of solid cancer, with 20–50% increased risks for smoke related cancers and +70% increased risk for non-melanoma skin cancer, but decreased risk for breast (−20%) and colorectal cancer (−25%). With 138 cancers, the incident RA cohort displayed a similar cancer pattern apart from non-decreased risks for colorectal cancer. TNF antagonist treated patients displayed solid cancer (nu200a=u200a67) risks largely similar to those of other patients with RA. Conclusion: The cancer pattern in patients treated with TNF antagonists mirrors those of other contemporary as well as historic RA cohorts. The consistent increase in smoking associated cancers in patients with RA emphasises the potential for smoking cessation as a cancer preventive measure in RA.

Time-dependent increase in risk of hospitalisation with infection among Swedish RA patients treated with TNF antagonists

Objectives: The degree to which treatment with tumour necrosis factor (TNF) antagonists may be associated with increased risks for serious infections is unclear. An observational cohort study was performed using prospectively collected data from the Swedish Biologics Register (ARTIS) and other national Swedish registers. Methods: First, in the ARTIS, all 4167 rheumatoid arthritis (RA) patients starting TNF antagonist treatment between 1999 and 2003 were identified. Secondly, in the Swedish Inpatient Register, all individuals hospitalised for any reason and who also carried a diagnosis of RA, between 1964 and 2003 (nu200a=u200a44u2009946 of whom 2692 also occurred in ARTIS), were identified. Thirdly, in the Swedish Inpatient Register, all hospitalisations listing an infection between 1999 and 2003 were identified. By cross-referencing these three data sets, RRs for hospitalisation with infection associated with TNF antagonist treatment were calculated within the cohort of 44u2009946 RA patients, using Cox regression taking sex, age, geography, co-morbidity and use of inpatient care into account. Results: Among the 4167 patients treated with TNF antagonists, 367 hospitalisations with infections occurred during 7776 person-years. Within the cohort of 44u2009496 RA patients, the RR for infection associated with TNF antagonists was 1.43 (95% CI 1.18 to 1.73) during the first year of treatment, 1.15 (95% CI 0.88 to 1.51) during the second year of treatment, and 0.82 (95% CI 0.62 to 1.08) for subjects remaining on their first TNF antagonist treatment after 2 years. Conclusion: Treatment with TNF antagonists may be associated with a small to moderate increase in risk of hospitalisation with infection, which disappears with increasing treatment duration.

Anti-tumour necrosis factor therapy in rheumatoid arthritis and risk of malignant lymphomas: relative risks and time trends in the Swedish Biologics Register

Background: Tumour necrosis factor (TNF) antagonists have proved effective as treatment against rheumatoid arthritis (RA), but the unresolved issue of whether the use of anti-TNF therapy increases the already elevated risk of lymphoma in RA remains a concern. Methods: Using the Swedish Biologics Register (ARTIS), the Swedish Cancer Register, pre-existing RA cohorts and cross-linkage with other national health and census registers, a national RA cohort (n u200a=u200a 67 743) was assembled and patients who started anti-TNF therapy between 1998 and July 2006 (n u200a=u200a 6604) were identified. A general population comparator (n u200a=u200a 471 024) was also assembled and the incidence of lymphomas from 1999 to 31 December 2006 was assessed and compared in these individuals. Results: Among the 6604 anti-TNF-treated RA patients, 26 malignant lymphomas were observed during 26 981 person-years of follow-up, which corresponded to a relative risk (RR) of 1.35 (95% CI 0.82 to 2.11) versus anti-TNF-naive RA patients (336 lymphomas during 365 026 person-years) and 2.72 (95% CI 1.82 to 4.08) versus the general population comparator (1568 lymphomas during 3 355 849 person-years). RA patients starting anti-TNF therapy in 1998–2001 accounted for the entire increase in lymphoma risk versus the two comparators. By contrast, RR did not vary significantly by time since start of first treatment or with the accumulated duration of treatment, nor with the type of anti-TNF agent. Conclusion: Overall and as used in routine care against RA, TNF antagonists are not associated with any major further increase in the already elevated lymphoma occurrence in RA. Changes in the selection of patients for treatment may influence the observed risk.

Cancer risk in patients with rheumatoid arthritis treated with anti-tumor necrosis factor alpha therapies: does the risk change with the time since start of treatment?

OBJECTIVEnTo determine the short-term and medium-term risks of cancer in patients receiving anti-tumor necrosis factor alpha (anti-TNFalpha) therapies that have proven effective in the treatment of chronic inflammatory conditions.nnnMETHODSnBy linking together data from the Swedish Biologics Register, Swedish registers of RA, and the Swedish Cancer Register, we identified and analyzed for cancer occurrence a national cohort of 6,366 patients with RA who first started anti-TNF therapy between January 1999 and July 2006. As comparators, we used a national biologics-naive RA cohort (n = 61,160), a cohort of RA patients newly starting methotrexate (n = 5,989), a cohort of RA patients newly starting disease-modifying antirheumatic drug combination therapy (n = 1,838), and the general population of Sweden. Relative risks (RRs) were estimated using Cox regression analyses, examining overall RR as well as RR by time since the first start of anti-TNF therapy, by the duration of active anti-TNF therapy, and by the anti-TNF agent received.nnnRESULTSnDuring 25,693 person-years of followup in 6,366 patients newly starting anti-TNF, 240 first cancers occurred, yielding an RR of 1.00 (95% confidence interval 0.86-1.15) versus the biologics-naive RA cohort, and similar RRs versus the other 2 RA comparators. RRs did not increase with increasing time since the start of anti-TNF therapy, nor with the cumulative duration of active anti-TNF therapy. During the first year following the first treatment start, but not thereafter, dissimilar cancer risks for adalimumab, etanercept, and infliximab were observed.nnnCONCLUSIONnDuring the first 6 years after the start of anti-TNF therapy in routine care, no overall elevation of cancer risk and no increase with followup time were observed.

Swedish registers to examine drug safety and clinical issues in RA

Data from several different monitoring systems are examined. The potential for registers based on data obtained from clinical practice, and linkage of such data to national health and population registers, is discussed. The approach described is a possible prototype for long term surveillance systems needed for the safe introduction of new treatments.

Pulmonary involvement in ankylosing spondylitis.

Thirty two patients with ankylosing spondylitis were investigated with a set of pulmonary function tests and the results compared with those for a control population. The patients had no complaints about lung symptoms and their chest radiographs were normal. The main pathological findings were reduced lung volumes, a raised closing volume/vital capacity ratio, and a decreased volumic airway conductance. The lung volume reduction correlated with disease duration, thoracic mobility, and degree of acute phase reaction. The stiff spondylitic thorax probably makes the main contribution to the impairment of lung function in these patients, but the findings in this study also suggest an involvement of the small airways. This type of pulmonary function testing seems valuable even in patients with ankylosing spondylitis without lung symptoms and it might be used as a tool in the staging of the disease, to evaluate treatment and to differentiate from fibrosis.

Risks of neurological and immune‐related diseases, including narcolepsy, after vaccination with Pandemrix: a population‐ and registry‐based cohort study with over 2 years of follow‐up

To investigate the association between vaccination with Pandemrix and risk of selected neurological and immune‐related diseases including narcolepsy.

A Swedish national post-marketing surveillance study of natalizumab treatment in multiple sclerosis

Background: A post marketing surveillance study was conducted to evaluate safety and efficacy of natalizumab in Swedish multiple sclerosis (MS) patients since its introduction in August 2006 until March 2010. Methods: Patients were registered in the web-based Swedish MS-registry at 40 locations and evaluated every 6 months. Adverse events and clinical outcomes were recorded. Results: One thousand one hundred and fifty-two patients were included (71.4% female) and 149 patients stopped treatment; the main reason was planned pregnancy. Anti-natalizumab antibodies were found in 4.5% (52 patients) of which 1.6% displayed persistent antibodies. Serious adverse events were rare, but included three cases with progressive multifocal leukoencephalopathy (PML). There were seven fatal cases, probably unrelated to the natalizumab treatment. For relapsing–remitting MS patients (nu2009=u2009901), mean Expanded Disability Status Scale (EDSS, −10.7%), Multiple Sclerosis Severity Scale (MSSS, −20.4%), Multiple Sclerosis Impact Scale (MSIS-29, physical −9.9%, psychological −13.3%) and Symbol Digit Modalities Test (SDMT, +10.7%) all showed significant improvements during 24 months of treatment with natalizumab. The Swedish web-based MS quality registry proved to function as a platform for post-marketing MS drug surveillance, providing long-term data regarding drug effects and adverse events beyond clinical trials. Conclusions: Our results indicate that natalizumab is generally well tolerated and has sustained efficacy for patients with active MS, though the risk of PML is still an important concern.