Evaluating the safety of ?-interferons in MS: A series of nested case-control studies.

ABSTRACT:

Objective

To examine the association between interferon-? (IFN-?) and potential adverse events using population-based health administrative data in British Columbia, Canada.

Methods

Patients with relapsing-remitting multiple sclerosis (RRMS) who were registered at a British Columbia Multiple Sclerosis Clinic (1995-2004) were eligible for inclusion and were followed up until death, absence from British Columbia, exposure to a non-IFN-? disease-modifying drug, or December 31, 2008. Incidence rates were estimated for each potential adverse event (selected a priori and defined with ICD-9/10 diagnosis codes from physician and hospital claims). A nested case-control study was conducted to assess the odds of previous IFN-? exposure for each potential adverse event with at least 30 cases. Cases were matched by age (±5 years), sex, and year of cohort entry, with up to 20 randomly selected (by incidence density sampling) controls. Odds ratios (ORs) with 95% confidence intervals (95% CIs) were estimated with conditional logistic regression adjusted for age at cohort entry.

Results

Of the 2,485 eligible patients, 77.9% were women, and 1,031 were treated with IFN-? during follow-up. From the incidence analyses, 27 of the 47 potential adverse events had at least 30 cases. Patients with incident stroke (OR_adj 1.83, 95% CI 1.16-2.89), migraine (OR_adj 1.55, 95% CI 1.18-2.04), depression (OR_adj 1.33, 95% CI 1.13-1.56), and hematologic abnormalities (OR_adj 1.32, 95% CI 1.01-1.72) were more likely to have previous exposure to IFN-? than controls.

Conclusions

Among patients with RRMS, IFN-? was associated with a 1.8- and 1.6-fold increase in the risk of stroke and migraine and 1.3-fold increases in depression and hematologic abnormalities.

SUBMITTER: de Jong HJI 

PROVIDER: S-EPMC5567323 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature