Why Do Men Have a Higher TJA Infection Risk Than Women?

Why do men who undergo total joint arthroplasty (TJA) experience a higher risk of periprosthetic joint infection (PJI) than women? Don’t they wash their hands as often?

A research team from Rothman Orthopaedic Institute in Philadelphia and the Iran University of Medical Sciences in Tehran went looking for an answer and found, interestingly enough, that the higher rates of infection are either tied to or correlated with prostatic hyperplasia. Their study, “Symptomatic Benign Prostatic Hyperplasia: A Risk Factor for Periprosthetic Joint Infection in Male Patients,” was published in the April 1, 2020 edition of The Journal of Bone and Joint Surgery.

Co-investigator Javad Parvizi, M.D., the James Edwards Professor of Orthopedic Surgery at the Sidney Kimmel Medical College, Rothman Orthopaedic Institute at Thomas Jefferson University Hospital in Philadelphia, explained to OTW why this might be the case: “We have been observing that male patients undergoing total joint arthroplasty had a higher rate of infection compared to female patients. Many studies have confirmed this finding. We wanted to find an explanation for this observation. We hypothesized that symptomatic Benign Prostatic Hyperplasia (BPH) may be a contributing factor to the higher rate of infection that is seen in male patients.”

“Benign Prostatic Hyperplasia, as the name implies, refers to enlargement of the prostate that usually happens with age. Symptoms such as poor urination stream, dribbling, incontinence, and others may arise when prostate is enlarged to a considerable size.”

The researchers began by looking at data from 12,902 male patients who underwent primary or revision TJA from January 2006 to April 2017. Most procedures involved the hip (57.8%) and were primary arthroplasties (86%). Of those, 386 (3%) had symptomatic BPH. Among this group, 250 patients with symptomatic BPH were identified and were matched 1:3 ratio with 708 controls.

The authors wrote, “The PJI rate was 7.9% in the symptomatic BPH group and 2.8% in the control group. Multivariate regression analysis in unmatched groups showed that symptomatic BPH was a strong independent risk factor for PJI. After matching for variables related to outcomes, symptomatic BPH remained a significant risk factor for PJI.”

“The most important finding,” said Dr. Parvizi to OTW, “and the first of its kind, is that symptomatic BPH does indeed increase the risk of PJI in male patients undergoing total joint arthroplasty.”