Literature Review
MS May Have a Measurable Prodrome
People who later develop multiple sclerosis (MS) have increased health care use during the five years before their first demyelinating events,...
SAN DIEGO—In the five years before multiple sclerosis (MS) symptom onset, patients are more likely to see a physician or be admitted to the hospital for problems related to the nervous system, sensory organs, musculoskeletal system, and genitourinary system, compared with controls, according to research presented at the ACTRIMS 2018 Forum.
In addition, patients with MS are more likely to see psychiatrists and urologists and to fill prescriptions related to the musculoskeletal system or the genitourinary system in the five years before MS onset.
“It is possible to measure and phenotype the MS prodrome five years before the clinical recognition of MS,” said Elaine Kingwell, PhD, a research associate in the Division of Neurology at the University of British Columbia in Vancouver, and colleagues. “Our findings inform the etiologically relevant time window and suggest that an earlier recognition and diagnosis of MS is feasible.”
Elaine Kingwell, PhD
A prior study by the researchers had identified increased health care use before a first demyelinating event among patients with MS, but the study did not examine the types of health care used.
Phenotypic Characteristics
To investigate the phenotypic characteristics of the MS prodrome, Dr. Kingwell and colleagues examined the medical diagnoses and therapeutic drug classes related to inpatient and outpatient health care encounters five years before the clinical recognition of MS. The researchers performed a population-based matched cohort study using linked health administrative and clinical data in four Canadian provinces between 1989 and 2014.
The investigators compared the reasons for physician and hospital encounters, using ICD-10 chapters or physician specialty, and prescriptions filled, using Anatomical Therapeutic Chemical System, level 1 drug classes. The researchers matched people with MS with as many as five people without any demyelinating disease by sex, year of birth, and postal code.
The study included two cohorts of people with MS. One cohort encompassed patients with a first demyelinating disease–related claim (ie, the administrative cohort), and the other cohort comprised patients with a neurologist-confirmed diagnosis of MS (ie, the clinical cohort). The researchers compared inpatient and outpatient encounters between cases and controls in the five years before the cases’ first demyelinating claim or clinically reported symptom onset.
Fewer Pregnancy-Related Encounters
The administrative cohort included 13,951 cases and 66,940 controls (about 73% women; average age, 43). The clinical cohort included 3,202 cases and 16,006 controls (about 74% women; average age, 36.5). Compared with controls, in the five years before the first demyelinating claim or symptom onset, cases had more physician and hospital encounters for the nervous system (rate ratio [RR] = 1.70–4.75), sensory organs (RR = 1.40–2.28), musculoskeletal system (RR = 1.19–1.70), and genitourinary system (RR = 1.17–1.59). Cases also had more encounters with psychiatrists (RR = 1.48–1.66) and urologists (RR = 1.49–1.80), and a higher proportion of filled prescriptions for hormonal preparations and for drugs related to the musculoskeletal or genitourinary systems (1.1–1.5 times higher). In contrast, cases had fewer pregnancy-related encounters, compared with controls (RR = 0.78–0.88).
“Research into factors that might cause or prevent MS should take the MS prodrome into account,” the researchers said.
—Jake Remaly
Suggested Reading
Wijnands JMA, Kingwell E, Zhu F, et al. Health-care use before a first demyelinating event suggestive of a multiple sclerosis prodrome: a matched cohort study. Lancet Neurol. 2017;16(6):445-451.