Study shows significant decreases in infections among people with psoriatic arthritis

Reviewed by Emily Henderson, B.Sc.Nov 2 2021

New research presented this week at ACR Convergence, the American College of Rheumatology's annual meeting, shows significant decreases in infections among people with psoriatic arthritis over the years 2012-2017. (Abstract #1783).

Psoriatic arthritis is a type of inflammatory arthritis that occurs in some patients with psoriasis. This particular arthritis can affect any joint in the body, and symptoms vary from person to person. Persistent inflammation from psoriatic arthritis can lead to joint damage.

Biologic therapies now available to treat psoriatic arthritis (PsA) can help control disease activity and prevent damage, but these medications increase infection risk. Since use of biologics to treat PsA has increased in recent years, researchers conducted this study to find out if infections had increased among these patients. Researchers looked at national trends in serious infections in people with PsA from 2012 to 2017 across the U.S using the national inpatient sample.

The study was conducted to gather data to help providers have informed discussions with their patients. Some patients are initially hesitant to start immunosuppressive agents for treatment and understanding this information can provide a clearer idea of how this risk of infection is translated in real life and helps differentiate the risk of minor infections from serious infections in this subset of patients."

Vagishwari Murugesan, MD, Senior Rheumatology Clinical and Research Fellow at Boston University Medical Center and study's co-author

Researchers used data from the National Inpatient Sample, which includes a sample of discharge information from community hospitals, excluding rehabilitation and long-term acute care facilities, and contains about seven million discharge records. They identified discharges with a PsA diagnosis with a principal or secondary diagnosis of serious infections: pneumonia, sepsis, urinary tract infection (UTI), and/or skin and soft-tissue infections using ICD-9 and ICD-10 diagnostic codes. They standardized results for 2012-2017 to match age distributions in the U.S. population in 2012. Then, they tested for trends over the years 2012-2017 to measure any increases in these serious infections.

In 2012, they found a total of 50,700 hospital discharge diagnoses of PsA, including 125 patients diagnosed with pneumonia, 230 patients with sepsis, 312 with a skin or soft-tissue infection, and 174 with a UTI. In 2017, there were 179,400 discharge diagnoses of PsA, with 344 patients diagnosed with pneumonia, 374 with sepsis, 681 with skin and soft-tissue infection, and 348 with a UTI. From 2012-2017, there were statistically significant drops in hospital discharges for sepsis, skin and soft-tissue infections and UTI when standardized for age, but no statistical differences in pneumonia trends.

"While the National Inpatient Sample does not have information on individual treatment for patients in the study, the data show a decrease in hospital discharges for sepsis, skin and soft-tissue infections, and UTI over the past several years. This information may help guide patients to make decisions regarding the management of their arthritis while understanding their infection risk," says Dr. Murugesan.