Use of intravenous immunoglobulin (IVIG) had no apparent effect on the risk of venous thromboembolism (VTE) in adults with dermatomyositis (DM), based on data from more than 400 individuals.
DM has been associated with an increased risk of VTE in previous studies, wrote Elizabeth T. Rotrosen, of Boston University and Brigham and Women’s Hospital, Boston, and colleagues. Although IVIG is often effective for DM patients with recalcitrant disease, it carries a boxed warning for increased thrombosis risk; however, the association between IVIG use and VTE risk in DM has not been well examined, the researchers said.
In a study published in JAMA Dermatology, the researchers identified 458 adults with DM based on the European Alliance of Associations for Reumatology/American College of Rheumatology criteria. The mean age of the participants was 51.8 years, 76% were female, and 82% were White. Of these, 178 were treated with IVIG and 280 were not. The mean duration of IVIG treatment was 32.9 months. The researchers used the chi square test to test for independence between binary variables, the Pearson chi square test to test for independence between categorical variables, and the unpaired t test to compare continuous variables in their statistical analysis.
A total of 23 patients experienced DM-associated VTEs; 6 in the IVIG group and 17 in the non-IVIG group (3.4% vs. 5.7%, P = .20), a nonsignificant difference. The patients in the IVIG group who experienced a DM-associated VTE all underwent IVIG treatment within 4 weeks before the event.
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immunoglobulin infusion with intravenous drip
The most common risk factors for VTE in both the IVIG and non-IVIG groups were malignant neoplasm (66.7% and 58.8%, respectively), followed by immobilization (16.7% and 35.3%, respectively) and tobacco use (16.7% and 23.5%, respectively).
“Notably, 5 of the IVIG-treated patients with DM who experienced a VTE also had at least 1 additional underlying risk factor for VTE, including 4 with malignant neoplasm,” the researchers wrote.
A total of 76 patients had cancer-associated DM, including 12 treated with IVIG and 64 not treated with IVIG. Of these, 14 experienced a VTE (4 IVIG patients and 10 non-IVIG patients).
The study findings were limited by several factors, including the retrospective design and small number of VTEs. Prospective studies are needed for better assessment of the VTE risk in patients with DM treated with IVIG, the researchers noted. However, the study is the largest known to explore the association between IVIG use and VTE risk in patients with DM, they said, and the results suggest that clinicians may continue IVIG use in these patients with considerations of risks and benefits on an individual basis.
The study received no outside funding. Ms. Rotrosen had no financial conflicts to disclose. Two coauthors reported financial relationships with Pfizer unrelated to this study.