A decade-long study of over 48,000 workers reveals that sticking to optimal lifestyle habits dramatically lowers the risk of several major cancers—especially for those with chronic inflammation.
Study: The association of life’s essential 8 scores trajectory patterns with the risk of all cancer types. Image Credit: Harbucks / Shutterstock
The “Life’s Essential 8” (LE8) is a comprehensive lifestyle assessment tool designed by the American Heart Association to reduce the risk of cardiovascular diseases by improving lifestyle habits.
A team of researchers from China recently assessed the impact of LE8 score trajectories over time on the risk of cancer among individuals working at a Chinese coal mining company. They found promising outcomes in participants with stably elevated LE8 scores. The study is published in the journal Scientific Reports.
Background
The “Life’s Essential 8” (LE8) covers eight key lifestyle factors: diet quality, physical activity, nicotine exposure, sleep health, body weight, blood glucose, cholesterol levels, and blood pressure. LE8-based evaluation and optimization of these factors have been found to significantly reduce the risk of chronic diseases, such as cardiovascular disease, stroke, and non-alcoholic fatty liver disease.
Since lifestyle habits and risk factors fluctuate over time due to life transitions, health conditions, or aging, a dynamic assessment of lifestyle factors over a long period of time is considered to be a more accurate alternative to single assessments that capture data only at a specific point.
LE8 trajectory modeling—a statistical method using latent mixture models to identify patterns of change over time—is a dynamic tool that monitors individuals' lifestyle and health metrics over time to overcome the limitations associated with clinical decision-making or the development of lifestyle recommendations based on static data.
A growing body of evidence indicates that each LE8 component can profoundly influence the risk factors associated with cancer development and progression. Given these associations, researchers hypothesized that long-term adherence to LE8 guidelines might be more beneficial for cancer prevention than shorter periods of adherence or suboptimal compliance.
With this hypothesis, they designed this study to explore the direct relationship between LE8 score trajectories over time and the risk of incident cancer in a comprehensive, prospective cohort study.
Study Design
The study included 48,330 participants from the Kailuan study who underwent three health examinations between 2006 and 2010 to determine their LE8 scores. The Kailuan study is a prospective cohort study conducted in Tangshan, China. Since June 2006, the study has included 101,510 active employees and retirees from the Kailuan Group Co., Ltd., which produces coal and chemical industrial products.
The LE8 scores of the participants were calculated using the algorithm proposed by the American Heart Association for all eight LE8 metrics. Based on their composite scores, participants were categorized into three levels: high, moderate, and low.
Cancer cases were identified using multiple methods, including biennial self-reports, medical reports, and hospital discharge summaries. However, lifestyle data were primarily self-reported, which may introduce recall bias.
Study Findings
The study identified three distinct LE8 score trajectories between 2006 and 2010, including the low-stable, moderate-stable, and elevated-stable trajectories. The low-stable trajectory included 21% of participants with persistently low LE8 scores; the moderate-stable trajectory included 49% of participants with persistently moderate LE8 scores; and the elevated-stable trajectory included 29% of participants with persistently high LE8 scores.
The study identified 2,306 new cancer cases during the 10.39-year (mean) follow-up period. The analysis controlling for potential confounding factors, including age, sex, and lifestyle behaviors, revealed that participants with higher LE8 scores had significantly lower overall cancer risks.
Specifically, participants from moderate-stable and high-stable trajectories exhibited a 15% and 21% lower risk of overall cancer, respectively, compared to those from the low-stable trajectory.
Regarding specific cancer types, the study found that participants with persistently moderate LE8 scores have 49% and 34% reduced risks of developing breast and liver cancers, respectively, compared to those with persistently low LE8 scores.
Similarly, participants with persistently high LE8 scores exhibited 27%, 51%, 31%, and 39% reduced risks of lung, breast, colorectal, and liver cancers, respectively. However, in sensitivity analyses, the reduced risk for liver cancer in the elevated-stable group was no longer statistically significant after excluding participants using medications (e.g., antihypertensives) or those diagnosed within the first year.
Notably, the study found that the reduced breast cancer risk due to persistently elevated LE8 scores was more pronounced in participants with increased serum C-reactive protein levels (a systemic marker of inflammation). This finding indicates that inflammation can potentially influence the association between LE8 score trajectories and cancer risk.
Study Significance
The study finds that maintaining persistently elevated LE8 scores over a period of four years can significantly reduce the overall cancer risk, as well as specific risks against lung, breast, colorectal, and liver cancers.
Similarly, maintaining persistently moderate LE8 scores over the same period has been found to significantly reduce the overall cancer risk, as well as specific risks against breast and liver cancers.
Moderate-to-high LE8 scores indicate a healthy lifestyle characterized by nutrient-rich dietary habits, regular physical activity, and adequate, high-quality sleep. All these factors are vital for maintaining a healthy body weight, blood glucose and cholesterol level, and overall metabolic homeostasis. Such metabolic improvements might be responsible for the inverse association observed between LE8 scores and cancer risk.
Smoking cessation is another critical component of LE8 that can potentially reduce the risk of exposure to carcinogens and, thus, can reduce the risk of cancer development.
However, the study has limitations: the cohort was geographically limited to a single industrial community in China, which may affect generalizability; dietary data were not comprehensively assessed (e.g., specific nutrient intake); lifestyle metrics relied on self-reports, which are subject to recall bias; and critical cancer-specific factors (e.g., reproductive history for breast cancer) were not analyzed. Additionally, LE8 trajectories remained relatively stable over time, potentially reflecting the health-conscious nature of the cohort.
Overall, the study findings underscore the importance of integrating LE8 into public health and clinical strategies for cancer prevention.