Tragically, the United States (US) surpassed one million documented deaths due to the coronavirus disease 2019 (COVID-19) pandemic. A convincing association between unhealthy lifestyle behaviors and poorer outcomes associated with COVID-19 infection has already been demonstrated and communicated by the Centers for Disease Control and Prevention in public health messaging. The US is experiencing not a pandemic, but a syndemic, specifically an unhealthy lifestyle behaviors-chronic diseases-COVID-19 syndemic. This syndemic has almost certainly significantly contributed to the more than one million deaths the United States has experienced during the pandemic. Decades of a high prevalence of unhealthy lifestyle behaviors laid the foundation for our current unfortunate situation by increasing vulnerability to a novel virus, especially among subgroups who have been historically marginalized. As such, a major pathway to defeating this syndemic is through the promotion of healthy living behaviors for all. Now is the time for action appropriate to meet the demands of a syndemic and a new path forward to a healthier and more equitable future.

Background

Poor lifestyle behaviors, including suboptimal diet, physical inactivity, and tobacco use, are leading causes of preventable diseases globally. Although even modest population shifts in risk substantially alter health outcomes, the optimal population-level approaches to improve lifestyle are not well established.

Methods and results

For this American Heart Association scientific statement, the writing group systematically reviewed and graded the current scientific evidence for effective population approaches to improve dietary habits, increase physical activity, and reduce tobacco use. Strategies were considered in 6 broad domains: (1) Media and educational campaigns; (2) labeling and consumer information; (3) taxation, subsidies, and other economic incentives; (4) school and workplace approaches; (5) local environmental changes; and (6) direct restrictions and mandates. The writing group also reviewed the potential contributions of healthcare systems and surveillance systems to behavior change efforts. Several specific population interventions that achieved a Class I or IIa recommendation with grade A or B evidence were identified, providing a set of specific evidence-based strategies that deserve close attention and prioritization for wider implementation. Effective interventions included specific approaches in all 6 domains evaluated for improving diet, increasing activity, and reducing tobacco use. The writing group also identified several specific interventions in each of these domains for which current evidence was less robust, as well as other inconsistencies and evidence gaps, informing the need for further rigorous and interdisciplinary approaches to evaluate population programs and policies.

Conclusions

This systematic review identified and graded the evidence for a range of population-based strategies to promote lifestyle change. The findings provide a framework for policy makers, advocacy groups, researchers, clinicians, communities, and other stakeholders to understand and implement the most effective approaches. New strategic initiatives and partnerships are needed to translate this evidence into action.

Implementation of prevention policies has often been impeded or delayed due to the lack of randomized controlled trials (RCTs) with hard clinical outcomes (eg, incident disease, mortality). Despite the prominent role of RCTs in health care, it may not always be feasible to conduct RCTs of public health interventions with hard outcomes due to logistical and ethical considerations. RCTs may also lack external validity and have limited generalizability. Currently, there is insufficient guidance for policymakers charged with establishing evidence-based policy to determine whether an RCT with hard outcomes is needed before policy recommendations. In this context, the purpose of this article is to assess, in a case study, the feasibility of conducting an RCT of the oft-cited issue of sodium reduction on cardiovascular outcomes and then propose a framework for decision-making, which includes an assessment of the feasibility of conducting an RCT with hard clinical outcomes when such trials are unavailable. We designed and assessed the feasibility of potential individual- and cluster-randomized trials of sodium reduction on cardiovascular outcomes. Based on our assumptions, a trial using any of the designs considered would require tens of thousands of participants and cost hundreds of millions of dollars, which is prohibitively expensive. Our estimates may be conservative given several key challenges, such as the unknown costs of sustaining a long-term difference in sodium intake, the effect of differential cotreatment with antihypertensive medications, and long lag time to clinical outcomes. Thus, it would be extraordinarily difficult to conduct such a trial, and despite the high costs, would still be at substantial risk for a spuriously null result. A robust framework, such as the one we developed, should be used to guide policymakers when establishing evidence-based public health interventions in the absence of trials with hard clinical outcomes.

Physical inactivity is a leading contributor to increased cardiovascular morbidity and mortality. Almost 500 million new cases of preventable noncommunicable diseases (NCDs) will occur globally between 2020 and 2030 due to physical inactivity, costing just over US$300 billion, or around US$ 27 billion annually (WHO 2022). Active adults can achieve a reduction of up to 35% in risk of death from cardiovascular disease. Physical activity also helps in moderating cardiovascular disease risk factors such as high blood pressure, unhealthy weight and type 2 diabetes. For people with cardiovascular disease, hypertension, type 2 diabetes and many cancers, physical activity is an established and evidence-based part of treatment and management. For children and young people, physical activity affords important health benefits. Physical activity can also achieve important cross-sector goals. Increased walking and cycling can reduce journeys by vehicles, air pollution, and traffic congestion and contribute to increased safety and liveability in cities.

Cardiovascular, respiratory, and related disorders (CVRDs) are the leading causes of adult death worldwide, and substantial inequalities in care of patients with CVRDs exist between countries of high income and countries of low and middle income. Based on current trends, the UN Sustainable Development Goal to reduce premature mortality due to CVRDs by a third by 2030 will be challenging for many countries of low and middle income. We did systematic literature reviews of effectiveness and cost-effectiveness to identify priority interventions. We summarise the key findings and present a costed essential package of interventions to reduce risk of and manage CVRDs. On a population level, we recommend tobacco taxation, bans on trans fats, and compulsory reduction of salt in manufactured food products. We suggest primary health services be strengthened through the establishment of locally endorsed guidelines and ensured availability of essential medications. The policy interventions and health service delivery package we suggest could serve as the cornerstone for the management of CVRDs, and afford substantial financial risk protection for vulnerable households. We estimate that full implementation of the essential package would cost an additional US$21 per person in the average low-income country and $24 in the average lower-middle-income country. The essential package we describe could be a starting place for low-income and middle-income countries developing universal health coverage packages. Interventions could be rolled out as disease burden demands and budgets allow. Our outlined interventions provide a pathway for countries attempting to convert the UN Sustainable Development Goal commitments into tangible action.