Lower VTE risk seen in atopic dermatitis vs other inflammatory diseases

Atopic dermatitis (AD) does not seem to induce an increase in the risk of venous thromboembolism (VTE) when considering underlying risk factors, suggests a study. Moreover, patients with AD show a lower VTE risk than those with rheumatoid arthritis (RA), Crohn's disease (CD), ulcerative colitis (UC), psoriatic arthritis (PsA), or ankylosing spondylitis (AS).

“The generally lower prevalence of VTE risk factors in patients with AD versus other immune-mediated inflammatory disease (IMIDs) may contribute to the lower VTE incidence for patients with AD,” said lead author Joseph F Merola, Division of Rheumatology, Department of Dermatology and Department of Medicine, Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts, US.

Merola and his team conducted this retrospective, observational, comparative cohort study using Optum Clinformatics United States claims data (2010‒2019) of adults with AD, RA, CD, UC, psoriasis, AS, or PsA. They then matched unaffected control patients in a 1:1 ratio with those with AD.

A total of 2,061,222 patients with IMIDs were identified. Of these, 1,098,633 had AD. Those with AD showed a higher VTE incidence than did unaffected, AD-matched control participants (0.73 vs 0.59 cases per 100 person-years). [J Am Acad Dermatol 2024;90:935-944]

However, when accounting for baseline VTE risk factors, AD did not show a significant association with a higher risk of VTE (hazard ratio [HR], 0.96, 95 percent confidence interval [CI], 0.90‒1.02). Notably, AD patients had a lower VTE risk than those with RA, CD, UC, AS, or PsA. On the other hand, VTE risk did not differ significantly between AD and psoriasis patients.

“The differing VTE risk profiles may be influenced by the higher prevalence of VTE risk factors in patients with RA, PsA, and AS,” Merola said. [Arthritis Care Res 2013;65:1600-1607; Arthritis Res Ther 2022;24:16; Ann Rheum Dis 2019;78:480-485]

“Additionally, VTE risk rises with increased disease activity (RA and IBD) or severity (psoriasis),” he said. [Ann Rheum Dis 2022;81:517-518; Ann Rheum Dis 2021;80:169-175; Lancet 2010;375:657-663]

Inflammation

The cause of VTE risk increase in patients with IMIDs remains unclear, but studies have found that chronic, systemic inflammation associated with IMIDs may lead to vascular endothelial injury and hypercoagulability, which then elevates the risk of VTE. [Ann Med 2021;53:1074-1081; Open Access Rheumatol 2022;14:231-242; Acta Gastroenterol Belg 2021;84:79-85]

Active or severe disease is associated with increased inflammation, potentially increasing VTE incidence. RA, PsA, psoriasis, and inflammatory bowel disease pathogenesis also shows an association with excessive tumour necrosis factor-α (TNF-α) signaling, which contributes to chronic inflammation. [Int J Mol Sci 2021;22:2719]

“While the relationship between TNF-α and VTE risk is unclear, excessive TNF-α may promote coagulability, leading to increased thrombosis risk,” the researchers said. [Arterioscler Thromb Vasc Biol 2018;38:2542-2543]

“These results may help inform shared decision-making between physicians and their patients with AD, particularly regarding the potential for increased VTE risk with Janus kinase inhibitor use,” Merola said.

“Future prospective studies are needed to elucidate how disease severity and activity influence VTE risk,” he added.