Abstract
BACKGROUND: Hypertension poses significant global health challenges, especially in urban settings where systemic complexity exacerbates its burden. This study aimed to assess whether integrated intervention strategies, tested using a system dynamics model (the Simulator), can improve hypertension control and reduce cardiovascular disease (CVD) events in São Paulo, Brazil. METHODS: The Simulator was constructed in Stella Architect to project the intervention impacts on hypertension outcomes. It quantifies a causal loop diagram using São Paulo-specific data on hypertension prevalence, cascade of care, and CVD events over 2011-2045. Validation comprised sensitivity and global sensitivity analyses to assess uncertainty. FINDINGS: The Base scenario reflecting interventions introduced in 2018-2019, showed improvements in screening and diagnosis compared to a no-intervention scenario. Integrated interventions of patient engagement and health system improvements increased controlled cases by 41% (95% UI: 33% to 47%) and reduced CVD events rates by 19% (UI: -29% to -6%) at 15 years. These interventions heightened diagnostic and treatment demand, highlighting the need for expanded healthcare capacity. Expanding this capacity further increased controlled cases by 44% (UI: 37% to 53%) and reduced CVD events rates by 20% (UI: -31% to -8%). The most comprehensive scenario, incorporating prevention measures, achieved a 44% increase in controlled cases (UI: 36% to 53%) and a 22% reduction in CVD events rates (UI: -32% to -10%), showing long-term impacts of prevention. INTERPRETATION: A combined strategy that engages patients, expands service capacity, and delays disease onset offers the greatest gains. It highlights the need to balance individual, systemic, and preventive approaches to reduce hypertension burdens in complex systems for health. Future steps include institutionalizing the Simulator within São Paulo's municipal strategies, and adapting it to other Latin American cities, fostering region-wide, evidence-based planning. FUNDING: This study was funded by the Novartis Foundation.