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Infections in patients diagnosed with multiple sclerosis: A multi-database study
R Persson1, S Lee2, M Ulcickas Yood3
1Boston Collaborative Drug Surveillance Program, Lexington, MA, USA.
Background:
Recent data on the rates of infections among patients with multiple sclerosis (MS) are sparse. The objective of this study was to quantify incidence of infections in patients with MS compared with a matched sample of patients without MS (non-MS).
Methods:
This study was conducted in two separate electronic medical databases: the United States Department of Defense (US-DOD) military health care system and the United Kingdom's Clinical Practice Research Datalink GOLD (UK-CPRD). We identified patients with a first recorded diagnosis of MS between 2001 and 2016 (UK-CPRD) or 2004 and 2017 (US-DOD) and matched non-MS patients. We identified infections recorded after the MS diagnosis date (or the matched date in non-MS patients) and calculated incidence rates (IRs) and incidence rate ratios (IRRs) with 95% confidence intervals (CIs) by infection site and type.
Results:
Relative to non-MS patients, MS patients had higher rates of any infection (US-DOD IRR 1.76; 95% CI 1.72-1.80 and UK-CPRD IRR 1.25; 95% CI 1.21-1.29) and a two-fold higher rate of hospitalized infections (US-DOD IRR 2.43; 95% CI 2.23-2.63 and UK-CPRD IRR 2.00; 95% CI 1.84-2.17). IRs of any infection were higher in females compared with males in both MS and non-MS patients, while IRs of hospitalized infections were similar between sexes in both MS and non-MS patients. The IR of first urinary tract or kidney infection was nearly two-fold higher in MS compared with non-MS patients (US-DOD IRR 1.88; 95% CI 1.81-1.95 and UK-CPRD IRR 1.97; 95% CI 1.86-2.09) with higher rates in females compared with males. IRs for any opportunistic infection, candidiasis and any herpes virus were increased between 20 and 52% among MS patients compared with non-MS patients. IRs of meningitis, tuberculosis, hepatitis B and C were all low.
Conclusion:
MS patients have an increased risk of infection, notably infections of the renal tract, and a two-fold increased risk of hospitalized infections compared with non-MS patients.
Insights
Multiple sclerosis (MS) patients face a higher risk of infections, particularly kidney and urinary tract infections, and a doubled risk of hospitalization due to infections compared to individuals without MS.
Area of Science:
- Neurology
- Infectious Diseases
- Epidemiology
Background:
- Limited recent data exists on infection rates in multiple sclerosis (MS) patients.
- This study aims to quantify infection incidence in MS patients versus a matched non-MS cohort.
Purpose of the Study:
- To compare infection incidence rates between patients with multiple sclerosis (MS) and matched controls without MS.
- To identify specific types and sites of infection that are more prevalent in MS patients.
Main Methods:
- Utilized two large electronic health databases: US-DOD and UK-CPRD.
- Identified MS patients and matched non-MS controls diagnosed between 2001-2017.
- Calculated incidence rates and rate ratios for various infections post-diagnosis.
Main Results:
- MS patients exhibited higher rates of any infection (IRR 1.25-1.76) and a two-fold higher rate of hospitalized infections (IRR 2.00-2.43).
- Urinary tract/kidney infections were nearly doubled in MS patients (IRR 1.88-1.97).
- Opportunistic infections, candidiasis, and herpes virus infections were also increased in MS patients.
Conclusions:
- Multiple sclerosis patients have a significantly increased risk of infections.
- Notably, MS patients face higher risks for renal tract infections and a doubled risk for hospitalized infections.
