Disease Severity More Likely to Predict Risk of Infection Than Anti-TNF Therapy for RA Patients

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Disease Severity More Likely to Predict Risk of Infection Than Anti-TNF

Therapy for RA Patients: Presented at EULAR

By Jerry Ingram

VIENNA, AUSTRIA -- June 14, 2005 -- Patients with rheumatoid arthritis

might not have an increased risk for serious bacterial infections due

to antitumor necrosis factors (anti-TNF) therapies, researchers said.

According to data presented here on June 11th at EULAR 2005, the

European Congress of Rheumatology, disease severity might be more

important in predicting which patients will experience serious

infections.

Presenter Carl Turesson, MD, fellow, department of rheumatology, Malmö

University Hospital, Sweden, explained that patients with rheumatoid

arthritis have an increased risk of infection compared with the general

population and that there have been a number of case reports showing

infections in patients treated with TNF blockers.

Dr. Turesson and his team set out to establish whether treatment with

anti-TNF treatment in itself predisposes patients to other infections,

mainly severe bacterial infections leading to hospitalization or death.

To accomplish this goal, they examined clinical data on 412 patients

with rheumatoid arthritis who were treated with etanercept or

infliximab using information on these patients from the south Swedish

Arthritis Treatment Group (SSATG) registry.

The control group comprised 580 patients with rheumatoid arthritis who

participated in a survey conducted in 1997. Information on these

control subjects included disease severity and treatment impacting.

The researchers linked the 2 registers together with Swedish national

registries for inpatient care and cause of death through December 31,

2001 in order to determine outcome.

They defined severe infection (sepsis, septic arthritis, meningitis,

peritonitis) as the first occurrence of inpatient care or death from

severe infection without inpatient care for severe infection.

Investigators estimated first severe infection events in those treated

with anti-TNF agents and those not treated with TNF blockers. They used

age- and sex-adjusted incidence density computations with TNF treatment

and disease severity as time-dependent covariates (Health Assessment

Questionnaire disability score, patient's global assessment, number of

previous disease-modifying antirheumatic drugs, present steroid

treatment).

" We found that disability was a significant predictor of infection, so

we adjusted for these in our analyses, " Dr. Turesson explained. " The

relative risk turned out to be close to 1. "

" If there is any relation in increase in risk, it's likely to be small

compared to the impact of disease severity, " he asserted.

In the anti-TNF-treated patients there were 8 serious infections (no

patients with meningitis, 1 with peritonitis, 3 with septic arthritis,

and 4 with Sepsis). In the control group there were 28 such events (1

patient with meningitis, 2 with peritonitis, 13 with septic arthritis,

and 12 with sepsis).

The data corresponds to age- and sex-adjusted incidence rates of 10.9

(95% confidence Interval [CI]: 0.1-21.7) and 6.5 (95% CI: 3.9-9.0)

severe infection events per 1,000 person-years. When controlling for

markers of disease severity 1 at a time, the age- and sex-adjusted rate

ratios (RR) were 0.89 to 1.15 in anti-TNF-treated subjects compared

with controls.

" So there's no evidence for an increase in risk of severe infections in

those patients treated with anti-TNF therapies, " concluded Dr.

Turesson.

" The take home message is that in patients with RA, the disease

severity is more important in predicting infections than anti-TNF

treatments, which is reassuring, " he added.

[Presentation title: No Increase of Severe Infections in RA Patients

Treated With TNF-Blockers. Abstract 0164]