Introduction to the Theme Issue on Dynamics of Health Behavior: Revisiting Systems Science for Population Health

Longitudinal experience of food insecurity & cigarette use in the early COVID-19 Pandemic, United States

Food insecurity is associated with cigarette smoking, yet little is known about how variability in the experience of food insecurity may relate to patterns of cigarette use. We sought to examine patterns of food insecurity and cigarette use during the COVID-19 pandemic (April 2020-March 2021). We analyzed longitudinal survey data from a nationally representative panel of adults in the United States (N = 7,880) from the Understanding Coronavirus in America Study. The primary independent variable was ten trajectories of food insecurity. Our dependent variable was past 7-day cigarette use (count of days used cigarettes). Poisson regression using generalized estimating equations was run controlling for key covariates. The prevalence of cigarette use on at least one day in the past week was lowest (17.5 %) for those who Remained Food Secure, and highest (57.9 %) among those who Became Fully Food Insecure, a group characterized by having high probability of becoming food insecure during the study period. Among those who reported at least one day of cigarette use in the past week, fewer than half (40.1 %) reported sustained use across all waves of the study. Those who Became Fully Food Insecure had an incidence rate ratio (IRR) of 1.73 (95 % CI: 1.18, 2.54) compared to those who Remained Food Secure with respect to number of smoking days. While different patterns of food insecurity are related to cigarette smoking at the population level, these results highlight that food insecurity, a key social need, may represent a novel strategy for informing reduction of tobacco use disparities.

Leveraging Complex Systems Science to Advance Sexual and Gender Minority Youth Health Research and Equity

Over the past two decades, sexual and gender minority (SGM) youth health inequities have remained the same or widened, highlighting the need for new approaches to foster health equity. Complex systems science (CSS) techniques must be added to our armamentarium because of the following: CSS techniques can model cyclical feedback loops inherent in the relationships between SGM youth health outcomes and their multilevel causes, thereby enhancing the integration of real-world complexity in scientific models; and CSS can simulate multiple hypothetical interventions, thereby identifying future interventions with great potential impact. We describe four promising CSS techniques for advancing SGM youth health equity.