Effect of case management on services use under the PRISMA coordination model: a nested matched cohort study

INTRODUCTION: Under the PRISMA coordination model, all older people benefit from several model components, but only subjects identified with moderate to severe disabilities are eligible for case management. The PRISMA model has proven its effectiveness at the population level. However, for the sub-group with case management, what is its effect on services use? STUDY: We used data from the PRISMA study on adults aged 75 or over at risk of functional decline to compare subjects exposed to case management to unexposed ones, matched for functional disabilities, age, and gender. We studied change in annual services use, contrasting the year of assignment to the previous year. RESULTS: Among subjects in the PRISMA experimental group, 18% were assigned a case manager. Matched pairs were created for 49 cases for which data were available before and after assignment. Change in the number of annual ER visits was similar across groups, but the number of annual hospitalisations tended to increase less for exposed subjects (p=0.08). Change in annual hours for home maintenance was similar across groups, but more hours of help for personal care were added for case-managed older people (p=0.01), possibly by increasing access to home care. This strengthens the value of case management in an ISD network.