Relationship Between Occupational Characteristics and Telomere Length in Female Nurses Aged 20-39 Years: A...

Background: Korean registered nurses face substantial cumulative occupational stress. Telomere length, a biomarker of cellular aging, is increasingly used in occupational stress research, but evidence on early-career Korean nurses is scarce. This study examined the association between occupational characteristics and telomere length in female nurses aged 20-39 years. Methods: Sixty-eight female nurses from a tertiary hospital in South Korea completed the questionnaires. We assessed demographics, occupational factors, burnout (Maslach Burnout Inventory), and sleep quality (Pittsburgh Sleep Quality Index-Korean [PSQI-K]). Salivary telomere length was measured using quantitative polymerase chain reaction (qPCR). Data were analyzed using t-tests, ANOVA with a Bonferroni post hoc test, Pearson correlations, and multivariable linear regression. Results: Participants showed moderate to high burnout levels (Emotional Exhaustion [EE] = 24.78 ± 10.96), with 41.2% exceeding the high EE threshold. Sleep quality was poor (PSQI-K = 7.90 ± 3.07), with 82.4% exceeding the cut-off. Univariable analyses revealed that younger age, unmarried status, shorter work experience, and higher personal accomplishment were associated with longer telomeres (all p < 0.05); multivariable analysis identified only age group as a significant predictor (B = -2.055 kb for nurses aged ≥30 years compared to those <30 years, p < 0.001). The model explained 83% of the variance in telomere length. Shift work, burnout, and sleep quality were not significantly associated with telomere length after controlling for age. Conclusions: Age was the main factor associated with telomere length in young female nurses, suggesting that biological manifestation of occupational effects may require longer exposure. The high prevalence of burnout and sleep disturbances warrants immediate organizational intervention. Saliva-based qPCR demonstrated reliable precision as a non-invasive method for biological monitoring in occupational health research. These findings provide a basis for future longitudinal studies examining the cumulative effects of occupational stress and inform targeted wellness interventions for early-career nurses.