Study finds high incidence of bullous pemphigoid in patients undergoing chronic dialysis

The retrospective cohort study from Taiwan revealed that the incidence rate of bullous pemphigoid per 100,000 person-years was 74.2 among patients undergoing chronic dialysis versus 25.2 among those in the control group.

Bullous pemphigoid is a rare skin condition which mainly affects the elderly. It usually starts with a raised, itchy rash. As the condition develops, large blisters can form on the skin. It may last a few years and can sometimes cause serious problems, but in most cases, the treatment can help manage the condition.

A high incidence of bullous pemphigoid is generally noted among dialysis patients. However, there is no clarity on whether or not chronic dialysis is an independent risk factor of bullous pemphigoid. Chia-Chen Wang, School of Medicine, Fu-Jen Catholic University, New Taipei City, Taiwan, and colleagues aimed to investigate the effect of chronic dialysis on the development of pemphigus and bullous pemphigoid.

For this purpose, the researchers performed a retrospective cohort study using Taiwan's National Health Insurance Research Database records between 2008 and 2019. A dialysis cohort was identified that comprised patients on peritoneal dialysis and chronic hemodialysis. The hazard ratios (HRs) for pemphigus and bullous pemphigoid were compared with those of a sex-, age-, and index-matched cohort; the results were then adjusted for various confounding factors.

The study led to the following findings:

• Among 93 538 patients on chronic dialysis and 93 538 patients in the control group, 287 and 139 developed incident bullous pemphigoid, and 45 and 35 developed incident pemphigus following a median follow-up of 3.7 and 5.6 years, respectively.
• The incidence rates of bullous pemphigoid in the dialysis patients and the control group were 74.2 and 25.2 per 100,000 person-years, respectively.
• The incidence rates of pemphigus in the dialysis patients and the control group were 11.6 and 6.3 per 100,000 person-years, respectively.
• Cox proportional hazard adjustment showed the HR for bullous pemphigoid in dialysis patients was 2.12 compared with the control group.
• Dialysis patients aged <75 years had an even higher risk of bullous pemphigoid development (5- to 8-fold) than the control group.
• The adjusted HR for pemphigus was not elevated in dialysis patients (adjusted HR 1.52).

"Physicians should be aware of the predisposition of patients with chronic dialysis to bullous pemphigoid," the researchers concluded.

Reference:

Tang, H., Sue, M., Chang, L., & Wang, C. Risk of bullous pemphigoid and pemphigus in patients on chronic dialysis: A nationwide population-based cohort study. The Journal of Dermatology. https://doi.org/10.1111/1346-8138.16948