Frequently Asked Questions

Life’s Essential 8 (LE8) is the American Heart Association framework used to quantify overall cardiovascular health on a 0–100 scale. In this study, it included 4 health behaviors—diet, nicotine exposure, physical activity, and sleep duration—and 4 biometric health factors—body mass index, blood lipids, blood glucose, and blood pressure. Higher LE8 scores indicated better overall cardiovascular health, and scores were classified as poor (0–49), intermediate (50–79), or ideal (80–100).

Yes. In this nationally representative South Korean cohort, participants with poor LE8 scores had a 2.49 times higher risk of suicide mortality than those with ideal LE8 scores (95% CI, 1.06–5.82). The study was observational, so it does not establish causality, but it found a significant association between worse overall cardiovascular health and higher suicide mortality during follow-up.

Suicide mortality increased across worsening LE8 categories. The mortality rate was 0.13 per 1,000 person-years in the ideal LE8 group, 0.30 per 1,000 person-years in the intermediate group, and 0.47 per 1,000 person-years in the poor group; the overall rate was 0.28 per 1,000 person-years.

Health behaviors were more strongly related to suicide mortality than biometric health factors. Compared with participants who had an ideal health behavior score (≥80), those with a poor health behavior score (<50) had a 2.59 times higher risk of suicide mortality (95% CI, 1.23–5.44). In contrast, the study found no clear association between biometric health factor scores and suicide risk.

In the fully adjusted model, nicotine exposure and body mass index were the only individual LE8 components significantly associated with suicide mortality. Higher nicotine exposure scores were associated with lower suicide mortality (HR, 0.91; 95% CI, 0.86–0.96), while higher BMI scores were associated with higher suicide mortality (HR, 1.10; 95% CI, 1.02–1.18). The other LE8 components showed nonsignificant negative associations in the adjusted model.

Yes. The association was stronger in younger adults, with a significant interaction by age (P = .014). In stratified analyses, each 10-point increase in LE8 score was associated with a 30% lower hazard of suicide mortality in adults younger than 50 years (HR, 0.70; 95% CI, 0.57–0.86), whereas no clear association was seen in those aged 50 years or older (HR, 1.08; 95% CI, 0.87–1.34).

Yes. The association between poor LE8 and higher suicide mortality remained similar across multiple sensitivity analyses. Compared with the ideal LE8 group, the hazard ratio for suicide mortality in the poor LE8 group was 2.48 (95% CI, 1.03–5.96) in the competing-risk analysis, 4.02 (95% CI, 1.35–11.98) after excluding deaths within the first 3 years, and 2.33 (95% CI, 1.04–5.21) in the multiple-imputation analysis.

This was a nationally representative cohort study using data from the 2007–2018 Korea National Health and Nutrition Examination Survey linked to the national death registry. The analysis included 54,382 adults aged 19 years or older without missing values, and the median follow-up was 9.67 years. Suicide mortality was defined as death from intentional self-harm using ICD-10 codes X60–X84.

The main limitations are that the study was observational, so it cannot establish a causal relationship between LE8 and suicide mortality, and LE8 was measured only at baseline. The authors also noted possible residual confounding because important factors such as psychiatric history beyond depression and social relationships were not measured, potential inaccuracy from self-reported health behaviors, the use of the dietary inflammatory index instead of standard HEI or DASH-based diet scoring, limited generalizability outside Korea, and a relatively small number of suicide deaths that may have made estimates less stable.

No. The study showed an association, not proof of causation. The authors explicitly stated that a causal relationship between LE8 and suicide risk cannot be established because of the observational study design, and they noted that LE8 may mark vulnerability to psychiatric and social risk factors rather than act as a direct causal factor.