Contributions
Abstract: P408
Type: Poster Sessions
Abstract Category: Clinical aspects of MS - Comorbidity
Background: Cardiovascular diseases, including ischemic heart disease, are the leading cause of death in the general North American population. In some chronic immune-mediated diseases, including psoriasis and rheumatoid arthritis, there is an increased risk of ischemic heart disease as compared to the general population which is not fully explained by major cardiovascular risk factors, possibly reflecting a role of inflammation.
Objective: To examine the risk of incident acute myocardial infarction (AMI) in the multiple sclerosis (MS) population as compared to a matched population without MS, controlling for traditional vascular risk factors.
Methods: We conducted a retrospective matched cohort study using population-based administrative (health claims) data in British Columbia and Manitoba, Canada over the period 1984-2016. We applied a validated case definition to identify incident cases of MS in each province. For each case we identified up to 5 controls without MS matched on age, sex and region. We compared the incidence of AMI between the MS cases and matched controls using incidence rate ratios (IRR). We used Cox proportional hazards regression to compare the risk of AMI between cases and controls, stratifying on birth year, using age as the time scale, and adjusting for sex, socioeconomic status, diabetes, hypertension, and hyperlipidemia. We report hazard ratios (HR) and 95% confidence intervals (95%CI). We pooled findings across provinces using meta-analysis, and assessed the sensitivity of our findings to unmeasured confounding such as smoking status using the E-value.
Results: In total we identified 14,565 persons with MS and 72,825 matched controls. Women comprised 73% of the cohorts. The crude incidence of AMI per 100,000 population was 146.2 (95%CI: 129.0-163.5) in the MS population and 128.8 (95%CI: 121.8-135.8) in the matched population. After age-standardization, the incidence of AMI was higher in the MS population than in the matched population (IRR 1.18; 95%CI: 1.03-1.36). After adjustment, the hazard (risk) of AMI was 60% higher in the MS population than in the matched population (HR 1.62; 95%CI: 1.39-1.90). The observed HR of 1.62 could only be explained away by an unmeasured confounder that was associated with both MS and AMI by a risk ratio of 2.62-fold, which is unlikely.
Conclusion: The risk of AMI is elevated in MS, and this is not fully accounted for by traditional vascular risk factors.
Disclosure: Ruth Ann Marrie receives research support from the MS Society of Canada, the MS Scientific and Research Foundation, the National Multiple Sclerosis Society, the Canadian Institutes of Health Research, CMSC, Research Manitoba and the Waugh Family Chair in Multiple Sclerosis.
Allan Garland, Elaine Kingwell, Allan Schaffer, Stella Leung, Randy Fransoo: Nothing to disclose.
Helen Tremlett is the Canada Research Chair for Neuroepidemiology and Multiple Sclerosis and in the last 3 years has received research support from: the MS Society of Canada, the MS Scientific and Research Foundation, the National Multiple Sclerosis Society; the Canadian Institutes of Health Research, the Canada Foundation for Innovation and the UK MS Trust.
Abstract: P408
Type: Poster Sessions
Abstract Category: Clinical aspects of MS - Comorbidity
Background: Cardiovascular diseases, including ischemic heart disease, are the leading cause of death in the general North American population. In some chronic immune-mediated diseases, including psoriasis and rheumatoid arthritis, there is an increased risk of ischemic heart disease as compared to the general population which is not fully explained by major cardiovascular risk factors, possibly reflecting a role of inflammation.
Objective: To examine the risk of incident acute myocardial infarction (AMI) in the multiple sclerosis (MS) population as compared to a matched population without MS, controlling for traditional vascular risk factors.
Methods: We conducted a retrospective matched cohort study using population-based administrative (health claims) data in British Columbia and Manitoba, Canada over the period 1984-2016. We applied a validated case definition to identify incident cases of MS in each province. For each case we identified up to 5 controls without MS matched on age, sex and region. We compared the incidence of AMI between the MS cases and matched controls using incidence rate ratios (IRR). We used Cox proportional hazards regression to compare the risk of AMI between cases and controls, stratifying on birth year, using age as the time scale, and adjusting for sex, socioeconomic status, diabetes, hypertension, and hyperlipidemia. We report hazard ratios (HR) and 95% confidence intervals (95%CI). We pooled findings across provinces using meta-analysis, and assessed the sensitivity of our findings to unmeasured confounding such as smoking status using the E-value.
Results: In total we identified 14,565 persons with MS and 72,825 matched controls. Women comprised 73% of the cohorts. The crude incidence of AMI per 100,000 population was 146.2 (95%CI: 129.0-163.5) in the MS population and 128.8 (95%CI: 121.8-135.8) in the matched population. After age-standardization, the incidence of AMI was higher in the MS population than in the matched population (IRR 1.18; 95%CI: 1.03-1.36). After adjustment, the hazard (risk) of AMI was 60% higher in the MS population than in the matched population (HR 1.62; 95%CI: 1.39-1.90). The observed HR of 1.62 could only be explained away by an unmeasured confounder that was associated with both MS and AMI by a risk ratio of 2.62-fold, which is unlikely.
Conclusion: The risk of AMI is elevated in MS, and this is not fully accounted for by traditional vascular risk factors.
Disclosure: Ruth Ann Marrie receives research support from the MS Society of Canada, the MS Scientific and Research Foundation, the National Multiple Sclerosis Society, the Canadian Institutes of Health Research, CMSC, Research Manitoba and the Waugh Family Chair in Multiple Sclerosis.
Allan Garland, Elaine Kingwell, Allan Schaffer, Stella Leung, Randy Fransoo: Nothing to disclose.
Helen Tremlett is the Canada Research Chair for Neuroepidemiology and Multiple Sclerosis and in the last 3 years has received research support from: the MS Society of Canada, the MS Scientific and Research Foundation, the National Multiple Sclerosis Society; the Canadian Institutes of Health Research, the Canada Foundation for Innovation and the UK MS Trust.