Reliability in long-term clinical studies of disease-modifying therapies for relapsing-remitting multiple sclerosis: A systematic review

User experience of applying AMSTAR 2 to appraise systematic reviews of healthcare interventions: a commentary

BACKGROUND

'A Measurement Tool to Assess Systematic Reviews, version 2' (AMSTAR 2) is a validated 16-item scale designed to appraise systematic reviews (SRs) of healthcare interventions and to rate the overall confidence in their results. This commentary aims to describe the challenges with rating of the individual items and the application of AMSTAR 2 from the user perspective.

DISCUSSION

A group of six experienced users (methodologists working in different clinical fields for at least 10 years) identified and discussed the challenges in rating of each item and the general use of AMSTAR 2 to appraise SRs. A group discussion was used to develop recommendations on how users could deal with the identified challenges. We identified various challenges with the content of items 2-16 and with the derivation of the overall confidence ratings on AMSTAR 2. These challenges include the need (1) to provide additional definitions (e.g., what constitutes major deviations from SR protocol on item 2), (2) to choose a rating strategy for multiple conditions on single items (e.g., how to rate item 5 if studies were selected in duplicate, but consensus between two authors was not reported), and (3) to determine rules for deriving the confidence ratings (e.g., what items are critical for such ratings). Based on these challenges we formulated specific recommendations for items 2-16 that AMSTAR 2 users could consider before applying the tool. Our commentary adds to the existing literature by providing the first in-depth examination of the AMSTAR 2 tool from the user perspective. The identified challenges could be addressed by additional decision rules including definitions for ambiguous items and guidance for rating of complex items and derivation of confidence ratings. We recommend that a team consensus regarding such decision rules is required before appraisal procedure begins.

TRIAL REGISTRATION

Not applicable.

Multiple sclerosis hospitalizations among users of oral disease-modifying therapies

BACKGROUND

Oral disease-modifying therapies, namely dimethyl fumarate, fingolimod and teriflunomide, have become standard treatments for multiple sclerosis. Clinical trials demonstrated a reduction in annual relapse rate, but real-world data is lacking, particularly in older adults. The objective of our study is to evaluate the real-world effectiveness of oral disease-modifying therapies among individuals with multiple sclerosis.

METHODS

We used Optum^TM Clinformatics^TM Data Mart, a large dataset representative of commercially insured individuals in the United States, to conduct a retrospective cohort study of adult users of three oral disease-modifying therapies from September 2010 through September 2015. The therapies of interest included dimethyl fumarate, teriflunomide, and fingolimod. Hospitalization for multiple sclerosis, an approximation of the clinical trial endpoint for relapse, was the study outcome. Cox proportional hazards models were built to evaluate the association of demographic and clinical factors with multiple sclerosis hospitalization. A subgroup analysis was performed on individuals ages 55 years or older.

RESULTS

We identified 1,823, 318, and 1,156 users of dimethyl fumarate, teriflunomide, and fingolimod that met our inclusion criteria, respectively. Rates of hospitalizations for multiple sclerosis were low among these 3,297 persons (1,041 ages 55+): 36/1,000 patient-years for dimethyl fumarate, 43/1,000 for teriflunomide, and 45/1,000 for fingolimod. Multiple sclerosis hospitalization was associated with therapy switching (adjusted hazard ratio 2.21, 95% confidence interval 1.57-2.84), minority (1.44, 1.10-1.89), and history of relapse in the year preceding oral therapy initiation (5.25, 3.89-7.09).

CONCLUSION

Oral disease-modifying therapies are comparably effective for the outcome of multiple sclerosis hospitalization, even in older adults.