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Abstract This study assessed survival for lung cancer patients meeting criteria for the National Lung Cancer Screening Program in Korea launched in 2019 and updated guideline reported by the US Preventive Service Task Force (USPSTF). We assessed all-cause mortality based on the Korean Lung Cancer Registry (KLCR), including lung cancer patients diagnosed in 2014–2016. We compared survival among lung cancer patients eligible for extended USPSTF criteria (age 50–80 years and ≥ 20 pack-years) and those meeting current criteria (age 54–74 years and ≥ 30 pack-years, current or within the past 15 years). The nearest neighbour propensity-score matching was performed to generate a matched set. Kaplan–Meier curves were generated to compare survival among groups; differences in survival were analyzed using the stratified log-rank test. The mortality risk was estimated based on a Cox proportional hazards regression model and the robust standard error was calculated. Of 8110 patients, 37.4% and 24.3% met the extended USPSTF eligibility criteria and National Lung Cancer Screening Program (NLCSP) criteria, respectively. Overall mortality risk was not significantly different between the extended younger age group and the NLCSP group (hazard ratio [HR] [95% confidence interval (CI)]: 0.78 [0.59–1.02]). The extended older age group had a significantly higher mortality risk (HR [95% CI]: 1.41 [1.26–1.58]). Mortality risk was not significantly different between patients who smoked 20–29 pack-years and those who smoked ≥ 30 pack-years (HR [95% CI]: 0.90 [0.79–1.03]). Lung cancer patients aged 50–53 years and those with a 20–29 pack-years smoking history exhibited similar mortality risk to individuals meeting current criteria, while patients aged 75–80 years were at a higher risk of death. Although we verified similar or higher mortality risks in extended subgroups, a careful assessment of the benefits and harms of the screening tests is necessary when contemplating the extension of criteria.

Cognitive aging widely varies among individuals due to different stress experiences throughout the lifespan and vulnerability of neurocognitive mechanisms. To understand the heterogeneity of cognitive aging, we investigated the effect of early adulthood stress (EAS) on three different hippocampus-dependent memory tasks: the novel object recognition test (assessing recognition memory: RM), the paired association test (assessing episodic-like memory: EM), and trace fear conditioning (assessing trace memory: TM). Two-month-old rats were exposed to chronic mild stress for 6 weeks and underwent behavioral testing either 2 weeks or 20 months later. The results show that stress and aging impaired different types of memory tasks to varying degrees. RM is affected by combined effect of stress and aging. EM became less precise in EAS animals. TM, especially the contextual memory, showed impairment in aging although EAS attenuated the aging effect, perhaps due to its engagement in emotional memory systems. To further explore the neural underpinnings of these multi-faceted effects, we measured long-term potentiation (LTP), neural density, and synaptic density in the dentate gyrus (DG). Both stress and aging reduced LTP. Additionally, the synaptic density per neuron showed a further reduction in the stress aged group. In summary, EAS modulates different forms of memory functions perhaps due to their substantial or partial dependence on the functional integrity of the hippocampus. The current results suggest that lasting alterations in hippocampal circuits following EAS could potentially generate remote effects on individual variability in cognitive aging, as demonstrated by performance in multiple types of memory.