Association between handgrip strength and suicidal ideation in Korean adults

Background: It remains unclear whether muscle strength directly links with suicidal thoughts in adults. Given that suicidal ideation is tightly linked to depressive mood, this study sought to investigate the association between handgrip strength and suicidal ideation independent of depressive mood. Methods: We performed a cross-sectional analysis of 14,325 adults from the Korean National Health and Nutrition Survey. Handgrip strength was measured by squeezing the handgrip dynamometer using the dominant hand. Suicidal ideation and depressive mood were assessed via the self-reported questionnaires. Logistic regression models were applied to calculate the odds ratio (OR) and 95% confidence interval (CI) for suicidal ideation per 1 kg increase in handgrip strength while adjusting for potential confounders. Results: The mean age of participants was 49.8 years, 44.7% of whom were male. Suicidal ideation was associated with elderly age, female sex, low socioeconomic status, unhealthy lifestyles, and more comorbid conditions. Depressive mood was similarly associated with each of these factors. Each 1 kg increase in handgrip strength reduced the odds of suicidal ideation in both sexes independent of depressive mood [OR (95% CI), 0.96 (0.94-0.99) for male and 0.97 (0.95-1.00) for female]; in subgroup analysis this association remained robust among elderly men [OR (95% CI), 0.94 (0.91-0.98)]. Limitation: Causality and the impact of unmeasured confounders were not addressed. Conclusion: Low handgrip strength is associated with suicidal ideation among adults. Future research is required to confirm our findings and to establish whether strength training can reduce suicidal behaviors, particularly in elderly men.