Validation of Administrative Case Definitions for Diabetes, Hypertension and Hyperlipidemia in Persons with MS and Their Application To Determine Temporal Trends in Prevalence (P06.164)

Abstract

Objective: To validate administrative claims-based case definitions for diabetes, hypertension, and hyperlipidemia in multiple sclerosis (MS) patients, and to determine the prevalence of these comorbidities in MS as compared to the general population. Background Although the impact of comorbidity on MS is of increasing interest, methods for comorbidity measurement in MS are poorly developed. Design/Methods: We used provincial administrative (health) claims data from Manitoba, Canada to identify persons with MS and an age, sex and geographically matched cohort from the general population. We developed case definitions for diabetes, hypertension, and hyperlipidemia using ICD-9/10 codes and prescription claims. We compared the case definitions against medical records in persons with MS to determine sensitivity, specificity, positive and negative predictive value, and agreement as measured by kappa (κ). To examine temporal trends in the age-adjusted prevalence of these conditions we applied the validated case definitions to administrative data from 1984-2006. Results: Depending on the definition, agreement between administrative case definitions and medical records ranged from κ = 0.51-0.69 for diabetes, κ = 0.21-0.71 for hyperlipidemia, and κ = 0.52-0.75 for hypertension. In 2005, the age-adjusted prevalence of diabetes in the MS population was 7.61% (95% confidence interval: 6.63-8.60), similar to the general population (8.28% [7.82-8.75]); rate ratio [RR] 0.91; 0.76-1.09). The age-adjusted prevalence of hypertension was 20.8% (19.1-22.5) in the MS population and 22.5% (21.7-23.3) in the general population (RR 0.91; 0.78-1.07). The age-adjusted prevalence of hyperlipidemia was 13.8% (12.4-15.1), in the MS and 15.1% (14.5-15.8) in the general population (RR 0.90; 0.67-1.22). The prevalence of all three conditions rose in the MS and general populations over the study period. Conclusions: Administrative data are a valid data source for surveillance of diabetes, hypertension, and hyperlipidemia in MS. The prevalence of these comorbidities is rising, and is similar in the MS and general populations. Supported by: Multiple Sclerosis Society of Canada. Disclosure: Dr. Marrie has nothing to disclose. Dr. Yu has nothing to disclose. Dr. Leung has nothing to disclose. Dr. Elliott has nothing to disclose. Dr. Blanchard has nothing to disclose.