Nonoptimal Temperature and Cardiovascular Health: A Scientific Statement

Geographic location, housing conditions, occupation, and individual exposure patterns are emphasized as important contextual factors shaping risk.

• Scope and motivation: Ambient, nonoptimal temperatures are identified as key environmental drivers of cardiovascular health, with rising global temperatures and more frequent extreme temperature events heightening urgency for understanding associated risks.
• Core association: Short-term exposure to both heat and cold is linked to increased risk of cardiovascular events, including myocardial infarction, stroke, heart failure decompensation, arrhythmias, and sudden cardiac death.
• Contextual amplifiers: Climate patterns, the built environment, socioeconomic factors, physiological vulnerability, and systemic inequities intensify these risks.

• Biological pathways: Autonomic and neurohormonal activation, endothelial dysfunction, inflammation, hemoconcentration, and impaired thermoregulation are described as mediators of temperature-related cardiovascular risk.

• Healthcare delivery: Nonoptimal temperatures influence not only disease incidence but also access to care and the organization of health services, including emergency demand, operational disruption, and resilience challenges for health systems.
• Environmental footprint considerations: The article notes a paradox where cardiovascular care contributes to greenhouse gas emissions, potentially offsetting benefits of keeping cardiovascular health protected in the context of climate-driven risks.

• Purpose: The statement synthesizes current knowledge about how nonoptimal temperature affects cardiovascular health, emphasizes exposure inequalities, and proposes strategies across individual, community, health system, and policy levels.
• Research agenda: It highlights gaps and priorities, such as improving exposure assessment, understanding long-term exposures and their interactions with medications and coexposures, and identifying risk modifiers.

• Notable limits: The content acknowledges variability in exposure assessment and knowledge about long-term exposure effects, and calls for coordinated actions to address these uncertainties.

It also calls for attention to health equity and system-level resilience in mitigation strategies.

• Integrated approach: The document advocates for combined efforts in research, clinical practice, and policy to mitigate rising temperature-related cardiovascular risks amid a changing climate.