Cost-Effectiveness of a Chronic Care Model for Frail Older Adults in Primary Care: Economic Evaluation Alongside a Stepped-Wedge Cluster-Randomized Trial.

Abstract

To evaluate the cost-effectiveness of the Geriatric Care Model (GCM), an integrated care model for frail older adults based on the Chronic Care Model, with that of usual care. Economic evaluation alongside a 24-month stepped-wedge cluster-randomized controlled trial. Primary care (35 practices) in two regions in the Netherlands. Community-dwelling older adults who were frail according to their primary care physicians and the Program on Research for Integrating Services for the Maintenance of Autonomy case-finding tool questionnaire (N=1,147). The GCM consisted of the following components: a regularly scheduled in-home comprehensive geriatric assessment by a practice nurse followed by a customized care plan, management and training of practice nurses by a geriatric expert team, and coordination of care through community network meetings and multidisciplinary team consultations of individuals with complex care needs. Outcomes were measured every 6months and included costs from a societal perspective, health-related quality of life (Medical Outcomes Study 12-item Short-Form Survey (SF-12) physical (PCS) and mental component summary (MCS) scales), functional limitations (Katz activities of daily living and instrumental activities of daily living), and quality-adjusted life years based on the EQ-5D. Multilevel regression models adjusted for time and baseline confounders showed no significant differences in costs ($356, 95% confidence interval=-$488-1,134) and outcomes between intervention and usual care phases. Cost-effectiveness acceptability curves showed that, for the SF-12 PCS and MCS, the probability of the intervention being cost-effective was 0.76 if decision-makers are willing to pay $30,000 per point improvement on the SF-12 scales (range 0-100). For all other outcomes the probability of the intervention being cost-effective was low. Because the GCM was not cost-effective compared to usual care after 24months of follow-up, widespread implementation in its current form is not recommended.