People with two autoimmune diseases, rheumatoid arthritis (RA) and Sjögren’s syndrome, are at an increased risk for developing carpal tunnel syndrome (CTS), and should be screened for CTS and made aware of this risk, according to a new study presented this week at the Association of Academic Physiatrists Annual Meeting in Puerto Rico.

The relationship between CTS and autoimmune diseases is still unclear. Although RA is a known risk factor for developing CTS, physicians still do not know its exact role. CTS involves compression of the median nerve through the wrist at the carpal tunnel, and its symptoms include pain, tingling, and numbness in the fingers. To find out more about the relationship between CTS and common autoimmune diseases, researchers at the Taipei Veterans General Hospital Department of Physical Medicine and Rehabilitation conducted a cohort study focusing on autoimmune rheumatic disease (ARD) and inflammatory bowel disease (IBD) patients.

“Patients with autoimmune diseases may be considered with variable conditions, including the involvement of peripheral nerve system. Yet, there were only suspicions regarding ARD/IBD and CTS due to lack of large-scale cohort study to verify. This study provides the epidemiological evidence to support the correlation. Carpal tunnel syndrome is a disease that may affect health-related quality of life. Early diagnosis when managing patients with RA and Sjögren’s syndrome with adequate early health education and treatment could decrease the influence of CTS,” said Po-Cheng Hsu, MD, the study’s co-author.

The researchers used patient records from the 2015 Longitudinal Health Insurance Database of Taiwan's National Health Insurance Research Database. They identified all patients who were diagnosed and enrolled with either ARD or IBD. They calculated the incidence rate and surgical rate of CTS among patients with individual diseases. They also analyzed the hazard ratio on comparison of age- and gender-matched control groups (1:1).

The study included 3,291 patients, including 2,591 females and 701 males, who were identified and compared with controls. The incidence rate of CTS was the highest in patients with Crohn’s disease, followed by scleroderma and RA. The incidence rate of CTS in the control group was 4.8%.

After they adjusted the data for age and sex, the researchers observed a significant increase in the hazard ratio for developing CTS in patients with Sjögren’s syndrome and RA. Overall, the rate of surgery, a treatment for CTS that does not improve with splinting or medications, was 0.2% in the ARD or IBD patients, and 0.3% in the control group, they found.

The study’s findings suggest that people with Sjögren’s disease and RA have an increased risk of CTS compared to the general population, and screening for CTS in patients with these autoimmune diseases may be warranted. “These findings provide information that clinical practitioners and patients may keep in mind: the classical symptoms of (numbness, tingling and paresthesia) may be related to CTS,” said Dr. Hsu. “The surgery rate in ARD/IBD seems to be no different from that in the general population, suggesting that they were not at risk for developing severe CTS. We will further investigate the therapeutic effects of different injection methods, but our research will not be limited to the patients with RA or Sjögren’s syndrome.”