Non-infectious comorbidity in patients with multiple sclerosis: A national cohort study in Sweden

Comorbidity is of significant concern in multiple sclerosis (MS). Few population-based studies have reported conditions occurring in MS after diagnosis, especially in contemporary cohorts.

To explore incident comorbidity, mortality and hospitalizations in MS, stratified by age and sex.

In a Swedish population-based cohort study 6602 incident MS patients (aged ≥18 years) and 61,828 matched MS-free individuals were identified between 1 January 2008 and 31 December 2016, using national registers. Incidence rates (IRs) and incidence rate ratios (IRRs) with 95% CI were calculated for each outcome.

IRs of cardiovascular disease (CVD) were higher among MS patients than MS-free individuals, (major adverse CVD: IRR 1.42; 95% CI 1.12-1.82; hemorrhagic/ischemic stroke: 1.46; 1.05-2.02; transient ischemic attack: 1.65; 1.09-2.50; heart failure: 1.55; 1.15-2.10); venous thromboembolism: 1.42; 1.14-1.77). MS patients also had higher risks of several non-CVDs such as autoimmune conditions (IRR 3.83; 3.01-4.87), bowel dysfunction (2.16; 1.86-2.50), depression (2.38; 2.11-2.68), and fractures (1.32; 1.19-1.47), as well as being hospitalized and to suffer from CVD-related deaths ((1.91; 1.00-3.65), particularly in females (3.57; 1.58-8.06)).

MS-patients experience a notable comorbidity burden which emphasizes the need for integrated disease management in order to improve patient care and long-term outcomes of MS.