SAN DIEGO – Compared with controls, patients who developed MS were more frequently admitted to the hospital or visited a physician for problems related to the nervous system, sensory organs, musculoskeletal system, and genitourinary system in the 5 years prior to MS onset, a multicenter matched cohort study found.
“People are seeking help for different conditions that are most likely related to their MS,” one of the study authors, Elaine Kingwell, PhD, said in an interview at the meeting held by the Americas Committee for Treatment and Research in Multiple Sclerosis. “It suggests there could be opportunity to recognize and possibly diagnose and treat MS earlier.”
In a previously published study (Lancet Neurol. 2017;16:445-51) led by Helen Tremlett, PhD, and first author Jose Wijnands, PhD, the team found increased health care utilization in people with MS across all health sectors – physician, hospital, and pharmacy (prescriptions filled).
For the current study, the team set out to identify early signs and symptoms that could define the MS prodrome. “We wanted to know why people went to the hospital, why people went to their physician, what kind of drugs they were prescribed, and what kind of specialists they saw,” explained Dr. Kingwell, an epidemiologist in the department of neurology at the University of British Columbia, Vancouver.
The researchers used health administrative and MS-specific data from four Canadian provinces to conduct a multicenter matched cohort study. Individuals were required to be in the province from 5 years pre-index date, measured as either the first demyelinating event in health administrative data or MS onset as determined by the treating neurologist, until the MS cases’ third demyelinating claim or diagnosis date. The potential for a prodromal period was examined in the 5 years pre-index date, and outcomes of interest were number of physician and hospital encounters per ICD-10 chapter, number of physician encounters per physician specialty, and percentage of people with one or more filled prescription per drug class.
The researchers used rate ratios and 95% confidence intervals to compare the rates of physician and hospital encounters between MS cases and controls and the proportion test to compare the percentage of people with one or more filled prescriptions between MS cases and controls. They used random-effects meta-analyses to pool results across Canadian provinces.
The population consisted of 13,951 MS patients and 66,940 controls derived from a health administration cohort and 3,202 MS patients and 16,006 controls derived from MS clinics. Compared with controls, in the 5 years before the first demyelinating claim or symptom onset, cases had more physician and hospital encounters for the nervous system (rate ratio = 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), Dr. Kingwell and her associates reported.
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 drugs related to the musculoskeletal or genitourinary systems (ranging from 1.1 to 1.5 times higher; P less than .02 for all associations). “While we did not examine each individual drug, we did group drugs by their therapeutic class,” Dr. Wijnands noted in an interview after the meeting. “As for the increased number of visits to psychiatrists, it is intriguing. We don’t necessarily know all the reasons why. It opens up a lot of questions for people to follow up on.”
In contrast, MS cases had fewer pregnancy-related encounters, compared with controls (RR = 0.78-0.88).
Dr. Wijnands acknowledged certain limitations of the study, including its reliance on administrative data to measure the prodromal period. “When we described the prodrome itself, we relied on ICD codes from the physician and hospital data as well as prescriptions filled. Issues or problems for which individuals do not seek medical attention, for instance, would not be captured in our study,” she said.
The study was funded by the National MS Society. Dr. Wijnands receives salary support from the Michael Smith Foundation for Health Research /The Koehle Family Foundation, coauthor Ruth Ann Marrie, MD, PhD, holds the Waugh Family Chair in Multiple Sclerosis, and Dr. Tremlett is funded by the Canada Research Chair Program. Dr. Kingwell reported having no financial disclosures.
SOURCE: Kingwell E et al. ACTRIMS Forum 2018, late-breaking poster 254.