The population effect of a national policy to incentivize chronic disease management in primary care in stroke: a population-based cohort study using an emulated target trial approach

BACKGROUND: Governments are investing in primary care policies that support chronic disease management. Large scale population-based evaluations are lacking. We aim to determine the effectiveness of government-funded chronic disease management policies to improve long-term outcomes (survival, hospital presentations, and preventive medication adherence) following stroke/Transient Ischemic Attack (TIA). METHODS: Using a population-based cohort we utilized the target trial methodology. Participants were identified through the Australian Stroke Clinical Registry (January 2012–December 2016) from 42 hospitals in the states of Victoria and Queensland and linked with state and national hospital, primary care, pharmaceutical, aged care, and death datasets. Registrants living in the community, not receiving palliative care and who survived to 18 months following stroke/TIA were included. The comparison was a Medicare claim for policy-supported chronic disease management, 7–18 months following stroke/TIA versus usual care. Outcomes were modelled using multi-level, mixed-effects inverse probability of treatment weighted regression. FINDINGS: 12,368 registrants were eligible (42% female, median age 70 years, 26% TIA), 45% had a chronic disease management claim. The difference in mean outcomes for participants with a claim, compared to those without, showed a 26% lesser mortality rate (adjusted hazard ratio [aHR]: 0.74, 95% confidence interval [CI]: 0.62, 0.87) and a greater adjusted Odds Ratio [aOR] of being adherent with preventive medications: antithrombotics (aOR: 1.16, 95% CI: 1.07, 1.26); lipid-lowering (aOR: 1.23, 95% CI: 1.13, 1.33). Impacts on hospital presentations were variable. INTERPRETATION: Government policies that financially support primary care physicians to provide structured chronic disease management improve survival in the long-term following stroke/TIA. FUNDING: 10.13039/501100000925National Health and Medical Research Council Australia