Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK.
Kenya Medical Research Institute (KEMRI), Nairobi, Kenya.
Sci Rep. 2024 Sep 2;14(1):20354. doi: 10.1038/s41598-024-70796-7.
Normal respiratory rates (RR) for children under five in the tropics are well-documented, but data for older children are limited. This study tracked RR changes with age and examined associations with nutritional status and environmental factors. We monitored rural Gambian children aged 6 months to 14 years, recording RR during home visits twice weekly over two rainy seasons. Using a generalized additive model, we constructed RR reference curves, and a linear mixed-effect model identified factors influencing RR. A total of 830 children provided 67,512 RR measurements. Their median age was 6.07 years (interquartile range 4.21-8.55) and 400 (48.2%) were female. Age, stunting, ambient temperature, and time of RR measurement were independent predictors of respiratory rate. Strikingly, children showing signs of illness had greater variability in repeat RR measurements. We constructed a RR reference chart for children aged one to 13 years and proposed a cutoff of > 26 breaths/min for raised RR among children aged > 5 years bridging an important gap in this age group. Although the time of data collection, nutritional status, and ambient temperature were predictors of RR, their effect size is not clinically significant enough to warrant a change in the current WHO guidelines owing to the prevailing uncertainty in the measurement of RR. The finding that RRs between repeat measurements were more variable among children with signs of illness suggests that a single RR measurement may be inadequate to reliably assess the status of sick children-a population in which accurate diagnosis is essential to enable targeted interventions with lifesaving treatment.
儿童的正常呼吸频率（RR）在热带地区已有充分记录，但关于年龄较大儿童的数据有限。本研究跟踪了 RR 随年龄的变化，并研究了其与营养状况和环境因素的关联。我们监测了冈比亚农村地区 6 个月至 14 岁的儿童，在两个雨季期间每周两次家访记录 RR。使用广义加性模型，我们构建了 RR 参考曲线，并使用线性混合效应模型确定了影响 RR 的因素。共有 830 名儿童提供了 67512 次 RR 测量。他们的中位年龄为 6.07 岁（四分位距 4.21-8.55），400 名（48.2%）为女性。年龄、发育迟缓、环境温度和 RR 测量时间是 RR 的独立预测因素。令人惊讶的是，有疾病迹象的儿童在重复 RR 测量中的变化更大。我们为 1 至 13 岁的儿童构建了 RR 参考图表，并提出了一个 RR 临界值（>26 次/分钟），用于判断 5 岁以上儿童的 RR 升高，这填补了该年龄组的一个重要空白。虽然数据收集时间、营养状况和环境温度是 RR 的预测因素，但由于 RR 测量存在普遍的不确定性，其效应大小在临床上还没有重要到足以改变当前世卫组织的指导方针。RR 重复测量之间的差异在有疾病迹象的儿童中更为明显，这表明单次 RR 测量可能不足以可靠地评估患病儿童的状况，而准确的诊断对于能够进行有针对性的干预以提供救生治疗至关重要。
