Kennedy J D, Edward L J, Bates D J, Martin A J, Dip S N, Haslam R R, McPhee A J, Staugas R E, Baghurst P
Department of Pulmonary Medicine, Women's and Children's Hospital, Adelaide, South Australia, Australia.
Pediatr Pulmonol. 2000 Jul;30(1):32-40. doi: 10.1002/1099-0496(200007)30:1<32::aid-ppul6>3.0.co;2-9.
Impaired respiratory function has been found frequently in ex-premature children, but it is unclear which specific factors influence this impairment the most. The aim of this study was to determine the importance of the contributions of birth weight, gestational age, neonatal respiratory disease, and its treatment on subsequent childhood lung function at age 11 years in a cohort of children of very low birth weight (VLBW; </=1,500 g). Detailed clinical histories were recorded, and lung function was measured in 60% (102 children) of surviving VLBW infants born 1981/1982, and compared with 82 matched control children (birth weight >2,000 g) of similar age. VLBW children were shorter and lighter than controls (P < 0.0001) at 11 years of age, and had reduced expiratory flows (P < 0.00001) and forced vital capacities (P < 0.001). The residual volume to total lung capacity ratio (RV/TLC ratio) was increased (P < 0.00001), while total lung capacity (TLC) remained unchanged. Those with bronchopulmonary dysplasia (BPD) had the lowest mean expiratory flows. Males had lower expiratory flows than females. On univariate analysis, gestational age by itself accounted for 8.8% of the explained variance in FEV(1) at 11 years of age, but birth weight accounted for 16% on its own; both together accounted for a further 0.2% (16.2%), suggesting that the latter was the dominant factor. On multivariate analysis, the contribution of birth weight and gestational age was small, and the best predictors at 11 years of age, which together explained 43.4% of the total variance in FEV(1), were log days of supplemental oxygen (9.6%) and a reported history of asthma (10.8%). For FEF(25-75), these predictors explained 7.2% and 13.4%, respectively, of the total explained variance of 40.6%. The relation between neonatal oxygen supplementation and childhood FEV(1) was such that up to 20 days of supplemental oxygen had little effect on subsequent FEV(1) at 11 years of age, but each additional week of supplemental oxygen after that time was associated with a progressive reduction in FEV(1) of 3%. These data confirm the significant role of supplemental oxygen in the neonatal period and a history of asthma on the subsequent reduction of expiratory flows in VLBW children. Birth weight was a more important prenatal factor than gestational age, but both were of lesser predictive significance than either supplemental oxygen or a reported history of asthma.
呼吸功能受损在早产儿童中很常见，但尚不清楚哪些特定因素对这种损害影响最大。本研究的目的是确定出生体重、胎龄、新生儿呼吸系统疾病及其治疗对极低出生体重（VLBW；≤1500g）儿童11岁时后续儿童期肺功能的贡献的重要性。记录了详细的临床病史，并对1981/1982年出生的存活VLBW婴儿中的60%（102名儿童）进行了肺功能测量，并与82名年龄相仿的匹配对照儿童（出生体重>2000g）进行了比较。VLBW儿童在11岁时比对照组更矮更轻（P<0.0001），呼气流量降低（P<0.00001），用力肺活量降低（P<0.001）。残气量与肺总量之比（RV/TLC比）升高（P<0.00001），而肺总量（TLC）保持不变。患有支气管肺发育不良（BPD）的儿童平均呼气流量最低。男性的呼气流量低于女性。单因素分析显示，胎龄本身占11岁时FEV₁解释变异的8.8%，但出生体重单独占16%；两者共同占0.2%（16.2%），这表明后者是主导因素。多因素分析显示，出生体重和胎龄的贡献较小，11岁时的最佳预测因素是吸氧天数（9.6%）和哮喘病史（10.8%），它们共同解释了FEV₁总变异的43.4%。对于FEF₂₅₋₇₅，这些预测因素分别解释了总解释变异40.6%中的7.2%和13.4%。新生儿吸氧与儿童期FEV₁之间的关系是，在11岁时，吸氧20天以内对后续FEV₁影响不大，但此后每增加一周吸氧时间，FEV₁就会逐渐降低3%。这些数据证实了新生儿期吸氧和哮喘病史在VLBW儿童后续呼气流量降低中的重要作用。出生体重是比胎龄更重要的产前因素，但两者的预测意义均小于吸氧或哮喘病史。
