The epidemiology of comorbidities among multiple sclerosis patients in northeastern Poland

To determine and compare comorbidity levels in the multiple sclerosis (MS) population in Poland using a matched cohort from the general population.

We compared our database (standardized medical histories and medical records) from a MS center at the Department of Neurology, Medical University of Bialystok, Poland) with local National Health Fund (NHF) data (all patients presenting to healthcare facilities with a diagnosis of MS (ICD 10: G35)). We identified 1299 MS cases from the NHF data and 952,434 age and geographically matched controls. We estimated the prevalence of depression, sleep disorders, epilepsy, hypertension, hyperlipidemia, diabetes, atherosclerosis, lung infections, thyroid disease, discopathy, and urinary tract infections in the MS population versus matched controls.

In all, 815 cases of MS (67.6% women and 32.4% men) were registered with the MS center. According to the patients' medical records (with ICD 10 coding), the most common comorbidities were hypertension (4.3%) and thyroid diseases (3.3%). In addition, in standardized medical histories comorbidities were reported by MS patients: depression/depressed mood in 37.6% of patients (67% of whom had sought treatment), pain in 69.6% patients, urinary incontinence in 39.2% patients (44.9% of whom were treated), memory-related problems and fatigue in 39.2% and 70.8% patients, respectively. In the local NHF data, the most common comorbidities were hypertension (8%), diseases that cause back pain [ICD 10:M50-54 (4.3%),G54-55 (3%), M47-48 (5.4%)], urinary tract infection (3.5%), depression (2.4%), hyperlipidemia (2%), and diabetes (2%). All comorbidities except depression and sleep disorders were more common in the matched controls than in the MS population. Diabetes and hyperlipidemia in the MS population were more common in men than women. Most patients (89%) were not treated with disease-modifying therapies.

The most common comorbidity in the MS population is hypertension. The MS population has an increased prevalence of depression versus the matched controls. MS patients-especially men and older individuals-are at increased risk of developing vascular diseases.