C-reactive protein/albumin ratio is associated with lung function among children/adolescents with cystic fibrosis: a three-year longitudinal study

ABSTRACT BACKGROUND: Chronic lung infections, inflammation and depletion of nutritional status are considered to be prognostic indicators of morbidity in patients with cystic fibrosis. The aim of this study was to investigate the association between inflammatory markers and lung function, nutritional status and morbidity among children/adolescents with cystic fibrosis. DESIGN AND SETTINGS: Prospective three-year longitudinal study conducted in an outpatient clinic in southern Brazil. METHODS: Children/adolescents aged 1-15 years with cystic fibrosis were enrolled. Nutritional status was determined from weight-to-length and body mass index-to-age z-scores and was classified as acceptable, at risk or nutritional failure. Tumor necrosis factor-α, interleukin-1β, myeloperoxidase, C-reactive protein and C-reactive protein/albumin ratio were analyzed. Lung function was evaluated based on the forced expiratory volume in the first second and morbidity according to the number of hospitalizations for pulmonary exacerbation and infections by Pseudomonas aeruginosa. Lung function, nutritional status and morbidity were the outcomes. Odds ratios and 95% confidence intervals were to evaluate the effect of baseline inflammatory markers on the clinical outcomes after three years of follow-up and p-values【研究背景】慢性肺部感染、炎症反应及营养状态耗竭被认为是囊性纤维化患者发病的预后指标。本研究旨在探讨囊性纤维化儿童及青少年的炎症标志物与肺功能、营养状态及发病情况之间的关联。【研究设计与实施场景】本研究为一项为期三年的前瞻性纵向研究，于巴西南部一家门诊诊所开展。【研究方法】本研究纳入年龄1~15岁的囊性纤维化儿童与青少年。营养状态通过体重身长比值、体质量指数年龄Z评分进行判定，分为可接受、风险及营养衰竭三类。检测分析的炎症标志物包括肿瘤坏死因子-α（tumor necrosis factor-α）、白细胞介素-1β（interleukin-1β）、髓过氧化物酶（myeloperoxidase）、C反应蛋白（C-reactive protein）及C反应蛋白/白蛋白比值。肺功能基于第一秒用力呼气容积进行评估，发病情况则以铜绿假单胞菌（Pseudomonas aeruginosa）感染所致肺部急性加重及感染的住院次数作为衡量指标。本研究的结局指标为肺功能、营养状态及发病情况。采用比值比及95%置信区间评估随访三年后基线炎症标志物对临床结局的影响，以及p值