Each year, roughly 1 in 60 adult patients with multiple sclerosis (MS) aged 65 years and under is hospitalized with urinary or kidney infections, a new study suggests. That’s more than quadruple the rate in a control cohort. Other types of infections affected patients with MS at a higher rate too.
“The relative risk of all types of inpatient infections and most types of outpatient infections was significantly elevated among the patients with MS. While we expected there to be increased relative risk of urinary or kidney and respiratory infections, we also found higher relative risk of viral, fungal, skin, and opportunistic infections,” said study lead author Riley Bove, MD, an assistant professor at the Weill Institute for Neurosciences at the University of California, San Francisco, who presented the findings at the meeting held by the Americas Committee for Treatment and Research in Multiple Sclerosis. She answered follow-up questions in an interview.
The researchers analyzed U.S. commercial insurer claim data from 2010 to 2019. They matched patients with MS (aged 18-64 years who had 2 or more diagnoses of MS at least 30 days apart and met other criteria) to controls who had diagnoses for any other condition at least 30 days apart and met other criteria.
A total of 87,755 patients were included in the study (mean age, 47.3 years; 75.7% female). In outpatient claims, urinary and kidney infections were the most common infections by far in patients with MS. They were also much more common than in the control cohort (14.23% vs. 7.82%; relative risk, 1.82; 95% confidence interval, 1.77-1.87; P < .0001).
Other results for outpatient claims — patients with MS versus controls — were: pneumonia/influenza (3.20% vs. 2.76%; RR, 1.16; 95% CI, 1.10-1.23; P < .0001), other respiratory/throat (30.31% vs. 30.05%; RR, 1.01; 95% CI, 0.99-1.02; P = .24), viral (6.83% vs. 5.74%; RR, 1.19; 95% CI, 1.15-1.23; P < .0001), skin (5.99% vs. 4.73%; RR, 1.26; 95% CI, 1.22-1.32; P < .0001), fungal (6.30% vs. 4.88%; RR, 1.29; 95% CI, 1.24-1.34; P < .0001), and opportunistic infections (1.02% vs. 0.68%; RR, 1.50; 95% CI, 1.35-1.66; P < .0001).
In regard to inpatient hospitalizations, the results for patients with MS versus controls were: urinary/kidney infections (1.60% vs. 0.36%; RR, 4.49; 95% CI, 3.98-5.08; P < .0001), pneumonia/influenza (0.77% vs. 0.35%; RR, 2.22; 95% CI, 1.94-2.54; P < .0001), other respiratory/throat (0.43% vs. 0.18%; RR, 2.37; 95% CI, 1.97-2.85; P < .0001), viral (0.23% vs. 0.09%; RR, 2.5; 95% CI, 1.99-3.36; P < .0001), skin (0.57% vs. 0.29%; RR, 1.95; 95% CI, 1.68-2.27; P < .0001), fungal (0.32% vs. 0.09%; RR, 3.69; 95% CI, 2.86-4.77; P < .0001), and opportunistic infections (0.07% vs. 0.04%; RR, 1.94; 95% CI, 1.26-2.97; P = .0024).
A Common and Treatable Condition
“Bladder dysfunction may be present in over 80% of persons in MS and can be a significant source of decreased function and quality of life in addition to increased health care costs and morbidity,” neurologist Barbara Giesser, MD, of the University of California, Los Angeles, said in an interview. “It is common among persons with MS to have bladders that do not empty urine completely. This can predispose them to bladder and kidney infections. Also, some patients may try to self-manage bladder symptoms by restricting fluids, and this can predispose them to infection as well.”
Giesser, who was asked to comment on the present research, advised neurologists to bring up urinary disorders themselves instead of waiting for patients to mention them. “Patients are often embarrassed to start a discussion about genitourinary dysfunction with their neurologists but will be very appreciative of the opportunity for it to be investigated and treated,” she said. “Neurologists should make sure that this area of neurologic function is addressed in the routine management of their patients with MS because bladder dysfunction, morbidity, and complications associated with it are treatable and preventable.”
For her part, Bove recommended “early and effective identification of risk, appropriate referral to first-line interventions such as pelvic floor physical therapy and patient education, and early referral to urologists skilled in treating neurogenic bladder. Further, it is important to monitor side effects of medications to ensure there are no unrecognized immune deficits.”
She also cautioned that “common symptoms of [urinary tract infections] in people with MS include symptoms that are also prevalent in neurogenic bladder: urgency, incontinence, and frequency. It is possible that having baseline lower urinary tract symptoms could mask the recognition of a urinary infection, resulting in delayed recognition and treatment of the infections.”
EMD Serono funded the study. Bove is funded by the National MS Society’s Harry Weaver Award. She has received research support from Biogen and Roche Genentech and consulting/advisory board fees from Alexion, Biogen, EMD Serono, Roche Genentech, Sanofi Genzyme, and Novartis. Giesser reported no disclosures.
This article originally appeared on MDedge.com, part of the Medscape Professional Network.