Therapeutic Inertia in Multiple Sclerosis Care: A Study of Canadian Neurologists

Introduction: According to previous studies, therapeutic inertia (TI) may affect 7 out of 10 physicians who care for MS patients, particularly in countries where clinical guidelines are not widely used. Limited information is available on the prevalence of TI and its associated factors across Canada. Objectives: (i) To evaluate factors associated with TI amongst neurologists caring for MS patients across Canada; (ii) to compare the prevalence of TI observed in Canadian neurologists to the prevalence of TI observed in Argentinean, Chilean, and Spanish neurologists (historical controls from prior studies). Design: One hundred and eight neurologists with expertise in MS were invited to participate in an online study in Canada. Participants answered questions regarding their clinical practice, risk preferences, management of 10 simulated case-scenarios. The design of that study was similar to that of the prior studies completed in Argentina and Chile (n = 115). TI was defined as lack of treatment initiation or escalation when there was clear evidence of clinical and radiological disease activity (8 case-scenarios, 440 individual responses). A TI score was created & defined as the number of case-scenarios that fit the TI criteria over the total number of presented cases (score range from 0 to 8), with a higher score corresponding to a higher TI. TI scores observed in the Canadian study were compared with those observed in Argentina and Chile, as both studies followed the same design, case-scenarios and methodologies. Predictors of TI included demographic data, MS specialist vs. general neurologist, practice setting, years of practice, volume of MS patients and risk preferences. Results: Fifty-five Canadian neurologists completed the study (completion rate: 50.9%). The mean age (±SD) was 38.3 (±15) years; 47.3% of the participants were female and 56.4% self-identified as MS specialists. Overall, 54 of 440 (12.3%) individual responses were classified as TI. 60% of participants displayed TI in at least one case-scenario. The mean TI score across Canada [0.98 (SD = 1.15)] was significantly lower than the TI score observed in the Argentinean-Chilean [1.82 (SD = 1.47); p < 0.001] study. The multivariable analysis revealed that older age (p = 0.018), years of experience (p = 0.04) and willingness to risk further disease progression by avoiding treatment initiation or treatment change (p = 0.043) were independent predictors of TI. Conclusions: TI in Canada was observed in 6 out of 10 neurologists, affecting on average 1 in 8 therapeutic decisions in MS care. TI in Canada is significantly lower than in the other studied countries. Factors associated with TI include older age, lower years of experience, and willingness to risk disease progression by avoiding treatment initiation or treatment change. Differences in clinical practice patterns and adherence/access to accepted MS guidelines may explain how TI in Canada differs significantly from TI in Argentina-Chile.