ative risk, researchers often use multivariate analysis to develop a number called a hazard ratio. If the number is less than one, then it means the substance in question is less hazardous than the control. If the number equals one, then the substance has the same risk as the control. And if the ratio is greater than oneA recent study has demonstrated that rheumatoid arthritis (RA) patients who use tumor necrosis factor (TNF) blockers are up to four times more likely to develop a serious bacterial infection than those who use only methotrexate. While the risk is not tremendously high, it is still a factor that needs to be taken into consideration by both patients as well as prescribing rheumatologists.

Infections are common in patients with rheumatoid arthritis and related disorders, but it is unclear if this is due to the treatments or the underlying disease process. Previous studies examining the impact of TNF blockers on infection have yielded variable results.

The goal of this most recent study was to determine if TNF inhibition raised the risk of serious bacterial infections compared to the use of methotrexate alone.

The study examined 2393 patients treated with TNF antagonists who were also on DMARDS, most often, methotrexate, and 2933 patients taking methotrexate alone. The most common TNF- blocker used was etanercept (Enbrel), followed by infliximab (Remicade).

During a median follow-up period of 17 months, infection-related hospitalization rates were 2.7% and 2.0% for the TNF blocker group and methotrexate-only group, respectively.

In order to calculate relative risk, researchers often use multivariate analysis to develop a number called a hazard ratio. If the number is less than one, then it means the substance in question is less hazardous than the control. If the number equals one, then the substance has the same risk as the control. And if the ratio is greater than one

eration by both patients as well as prescribing rheumatologists.

Infections are common in patients with rheumatoid arthritis and related disorders, but it is unclear if this is due to the treatments or the underlying disease process. Previous studies examining the impact of TNF blockers on infection have yielded variable results.

The goal of this most recent study was to determine if TNF inhibition raised the risk of serious bacterial infections compared to the use of methotrexate alone.

The study examined 2393 patients treated with TNF antagonists who were also on DMARDS, most often, methotrexate, and 2933 patients taking methotrexate alone. The most common TNF- blocker used was etanercept (Enbrel), followed by infliximab (Remicade).

During a median follow-up period of 17 months, infection-related hospitalization rates were 2.7% and 2.0% for the TNF blocker group and methotrexate-only group, respectively.

In order to calculate relative risk, researchers often use multivariate analysis to develop a number called a hazard ratio. If the number is less than one, then it means the substance in question is less hazardous than the control. If the number equals one, then the substance has the same risk as the control. And if the ratio is greater than one

ble results.

The goal of this most recent study was to determine if TNF inhibition raised the risk of serious bacterial infections compared to the use of methotrexate alone.

The study examined 2393 patients treated with TNF antagonists who were also on DMARDS, most often, methotrexate, and 2933 patients taking methotrexate alone. The most common TNF- blocker used was etanercept (Enbrel), followed by infliximab (Remicade).

During a median follow-up period of 17 months, infection-related hospitalization rates were 2.7% and 2.0% for the TNF blocker group and methotrexate-only group, respectively.

In order to calculate relative risk, researchers often use multivariate analysis to develop a number called a hazard ratio. If the number is less than one, then it means the substance in question is less hazardous than the control. If the number equals one, then the substance has the same risk as the control. And if the ratio is greater than one

ethotrexate alone. The most common TNF- blocker used was etanercept (Enbrel), followed by infliximab (Remicade).

During a median follow-up period of 17 months, infection-related hospitalization rates were 2.7% and 2.0% for the TNF blocker group and methotrexate-only group, respectively.

In order to calculate relative risk, researchers often use multivariate analysis to develop a number called a hazard ratio. If the number is less than one, then it means the substance in question is less hazardous than the control. If the number equals one, then the substance has the same risk as the control. And if the ratio is greater than one

ative risk, researchers often use multivariate analysis to develop a number called a hazard ratio. If the number is less than one, then it means the substance in question is less hazardous than the control. If the number equals one, then the substance has the same risk as the control. And if the ratio is greater than one, it means the substance is more hazardous than the control.

TNF blocker use was associated with a hazard ratio of 1.9 for serious bacterial infection. So, TNF therapy combined with DMARD therapy is more hazardous than methotrexate alone as far as risk of infection.

The incidence of infections was highest within 6 months of initiating TNF inhibition therapy.

The most common serious infections in both groups were pneumonia/ lung abscess (empyema) followed by cellulitis/soft tissue infection.

The efficacy of TNFantagonist therapy for most rheumatoid arthritis patients needs to be balanced against the potential harm of an increased risk of infection associated with these agents. Vigilant monitoring for infection is recommended when using these agents.

(Curtis JR, Patkar N, Xie A, Martin C, Allison JJ, Saag M, Shatin D, Saag KG. Risk of serious bacterial infections among rheumatoid arthritis patients exposed to tumor necrosis factor α antagonists. Arthritis Rheum 2007;56:1125-1133).