Increased Risk of Invasive Cervical Cancer in Women Taking TNF Inhibitors for RA

Women with rheumatoid arthritis (RA) have an increased risk of developing cervical dysplasia compared with women without RA and have a higher risk of developing invasive cervical cancer if they are taking tumor necrosis factor (TNF) inhibitors to treat their RA, according to a nationwide register-based cohort study from Sweden.¹

Previous studies assessing the risk of cervical dysplasia and neoplasia in women with RA have shown mixed results, but unlike these earlier studies, the Swedish study considered TNF inhibitors while also accounting for cervical screening patterns and other risk factors, including age, comorbidities, education level, marital status, and prior hospitalizations.

“Because TNF inhibitors cause immunosuppression and are thought to decrease the body’s ability to fight pathogens, including viral infections, we wanted to see what impact these treatments might have on patients’ risk of developing a virus-associated cancer like cervical cancer,” said Hjalmar Wadström, MD, Clinical Epidemiology Unit, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden, in an e-mail interview with Rheumatology Advisor.

“Although our study is not the first to consider TNF inhibitor use, previous studies only included women with a history of cervical neoplasia or did not account for cervical cancer screenings. We felt it was important to take cervical screening patterns into account because studies have shown a several-fold higher risk of cervical cancer in women who do not receive regular screenings,” he reported.

Dr Wadström and colleagues’ study included 34 984 biologic-naive women with RA, 9629 women who started a TNF inhibitor as their first biologic, and 300 331 comparators from the general population (matched 1:10). Compared with the biologic-naive and general population cohorts, the TNF inhibitor cohort was slightly younger (56 years vs 62 and 61 years, respectively), had higher education levels, and had more comorbidities; however, the cohorts were well matched overall. All patients were treated through Sweden’s publically funded healthcare system and followed up from 1999 to 2012. The investigators noted that TNF inhibitors were introduced in Sweden during the study period and that their use gradually increased to include one-third of all patients.