Background Preterm infants face unique stress states in early life. Early-life stress has been associated with changes in cortisol reactivity and behavioral abnormalities later in childhood in non-preterm populations. The Neonatal Infant Stressor Scale (NISS) has been used to estimate infant stress in the neonatal intensive care unit (NICU) but has not been biomarker validated. The relationship between NISS scores and salivary cortisol is unknown. The aim of this study is to test the association between NISS scores and salivary cortisol in the NICU Hospital Exposures and Long-Term Health (NICU-HEALTH) preterm birth cohort. Methods Three hundred and eighty-six salivary cortisol specimens were collected from 125 NICU-HEALTH participants during the NICU hospitalization. NISS scores were calculated to represent the infant’s experience in the 6 hours prior to specimen collection. Adjusted mixed-effect regression models were used to assess the association between each NISS score and salivary cortisol. Results Acute and total NISS scores were significantly associated with salivary cortisol level ( P = 0.002 and 0.05, respectively). The chronic NISS score was not associated with salivary cortisol levels. Caffeine treatment and postmenstrual age of the infant were important covariates in all models. Conclusion Acute and total NISS score are associated with salivary cortisol level in hospitalized moderately preterm infants.

中文翻译：

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新生儿压力量表与早产儿唾液皮质醇的临床验证

背景早产儿在早期生活中面临着独特的压力状态。早期生活压力与非早产人群童年后期皮质醇反应性的变化和行为异常有关。新生儿婴儿压力量表 (NISS) 已被用于评估新生儿重症监护病房 (NICU) 中的婴儿压力，但尚未经过生物标志物验证。NISS 评分与唾液皮质醇之间的关系尚不清楚。本研究的目的是在 NICU 医院暴露和长期健康 (NICU-HEALTH) 早产队列中测试 NISS 评分与唾液皮质醇之间的关联。方法 在 NICU 住院期间，从 125 名 NICU-HEALTH 参与者中收集了 386 份唾液皮质醇标本。计算 NISS 分数以代表婴儿在标本采集前 6 小时内的经历。调整后的混合效应回归模型用于评估每个 NISS 评分与唾液皮质醇之间的关联。结果 急性和总 NISS 评分与唾液皮质醇水平显着相关（分别为 P = 0.002 和 0.05）。慢性 NISS 评分与唾液皮质醇水平无关。咖啡因治疗和婴儿的经后年龄是所有模型中的重要协变量。结论 住院中度早产儿急性和总 NISS 评分与唾液皮质醇水平相关。结果 急性和总 NISS 评分与唾液皮质醇水平显着相关（分别为 P = 0.002 和 0.05）。慢性 NISS 评分与唾液皮质醇水平无关。咖啡因治疗和婴儿的经后年龄是所有模型中的重要协变量。结论 住院中度早产儿急性和总 NISS 评分与唾液皮质醇水平相关。结果 急性和总 NISS 评分与唾液皮质醇水平显着相关（分别为 P = 0.002 和 0.05）。慢性 NISS 评分与唾液皮质醇水平无关。咖啡因治疗和婴儿的经后年龄是所有模型中的重要协变量。结论 住院中度早产儿急性和总 NISS 评分与唾液皮质醇水平相关。