Use of Recommended Tests Before Starting Immunomodulatory Agents for Chronic Inflammatory Skin Diseases Varies

Although testing for the presence of certain conditions prior to initiating immunomodulatory treatment for chronic inflammatory skin diseases (CISDs) such as psoriasis, hidradenitis suppurativa, or atopic dermatitis is recommended, a study published in JAMA Dermatology found that less than 60% of patients in the US receive recommended pretreatment testing.

Biologic immunomodulatory agents have become increasingly important in dermatologic practice and can effectively treating CISDs. However, screening for hepatitis B and C and latent tuberculosis (TB) is recommended prior to treatment with immunomodulatory agents due to concerns that they may reactivate TB or hepatitis B and C, or that they may increase the risk of infections, myelosuppression, and hepatotoxicity. But past research suggests laboratory testing is underutilized in this setting, the study authors explained.

Using deidentified national commercial insurance claims data from MarketScan, the researchers evaluated the prevalence of pretreatment testing in patients with CISDs from December 31, 2002, to December 31, 2020. The database encompasses information on plan enrollment dates, health care utilization, demographics, inpatient and outpatient diagnoses, procedures, and pharmacy dispensing.

Blood samples | Image credit: Daniel CHETRONI – stock.adobe.com

A total of 122,308 patients with CISDs (median [IQR] age, 49 [38-58] years)—including psoriasis, hidradenitis suppurativa, or atopic dermatitis—who started immunomodulatory treatment were included in the study. The immunomodulatory agents used were methotrexate (n = 28,684), tumor necrosis factor α (TNF-α) inhibitors (n = 40,965), interleukin (IL)–17A inhibitors (n = 9799), ustekinumab (n = 12,841), IL-23 inhibitors (n = 6116), dupilumab (n = 7787), and apremilast (n = 16,116). The main outcome was the proportion of patients who underwent the recommended TB, hepatitis, and liver function screening tests, as well as complete blood cell counts and lipid panels within 6 months prior to treatment and in the 2 years following treatment initiation.

The most common test in the 6 months prior to treatment was complete blood cell count, which 41% to 69% of patients received across the treatment groups. TB screening was conducted in 11% to 59% of patients across the treatment groups prior to treatment, with 3% to 26% receiving updated TB tests 1 year later. Pretreatment hepatitis panels were done in 13% to 41% of patients across treatment groups.

The highest proportions of patients were screened for TB prior to treatment with IL-23 inhibitors, IL-17A inhibitors, TNF-α inhibitors, and ustekinumab (59%, 53%, 50%, and 46%, respectively). Patients treated with IL-17A inhibitors (26%), ustekinumab (23%), IL-23 inhibitors (22%), and TNF-α inhibitors (15%) most commonly had follow-up TB tests within 181 to 365 days after treatment compared with other treatment groups. The lowest pretreatment testing levels were seen in patients treated with apremilast or dupilumab, both of which do not require laboratory monitoring.

“Among patients with CISDs in the US starting treatment with systemic immunomodulatory agents, less than 60% received recommended pretreatment testing in the 6 months before treatment initiation,” the authors wrote. “Although this practice represents a break from current recommendations, when taken in combination with higher rates of baseline testing (an additional 17 percentage points) in the 6 to 12 months before treatment initiation and the potential for additional laboratory testing in settings that are not captured by this dataset (eg, hospital stays, occupational health offices), the gap may not be as large as this estimate.”

The authors pointed out that there was substantial heterogeneity in rates of testing, despite all of the tests having similar monitoring recommendations. Data from clinical practices would be valuable to improve the understanding of the heterogeneity of screening and to evaluate whether outcomes differ between patients who are screened and those who are not.

The study also had limitations. The authors noted that it was a descriptive analysis based on insurance claims data, allowing for evaluation of insurance-covered laboratory monitoring prior to treatment with immunomodulatory agents but not for the appropriateness of testing. The variations seen in the study also suggest further research is needed to optimize and evaluate the appropriateness of testing practices.

Reference

Schneeweiss MC, Shay D, Ly S, et al. Prevalence of pretreatment testing recommended for patients with chronic inflammatory skin diseases. JAMA Dermatol. Published online January 31, 2024. doi:10.1001/jamadermatol.2023.5895