There are limited data about the range of diseases, natural history, age-appropriate end-points and optimal care for children with pulmonary hypertension (PH), including the need for developing high-quality patient registries of children with diverse forms of PH to enhance care and research. Our objective was to characterise the distribution and clinical features of diseases associated with paediatric PH, including natural history, evaluation, therapeutic interventions and outcomes, as defined by the World Symposium on Pulmonary Hypertension (WSPH) classification.

1475 patients were enrolled into a multisite registry across the Pediatric Pulmonary Hypertension Network (PPHNet), comprised of eight interdisciplinary PH programmes.

WSPH Groups 1 (pulmonary arterial hypertension (PAH)) and 3 (lung or hypoxia-related PH) were the most common primary classifications (45% and 49% of subjects, respectively). The most common Group 3 conditions were bronchopulmonary dysplasia and congenital diaphragmatic hernia. Group 1 disease was predominantly associated with congenital heart disease (60% of Group 1 cases) and idiopathic PAH (23% of Group 1 cases). In comparison with Group 1, Group 3 subjects had better disease resolution (hazard ratio 3.1; p<0.001), tended to be younger at diagnosis (median (interquartile range) age 0.3 (0.0–0.6) versus 1.6 (0.1–6.9) years; p<0.001) and were more often male (57% versus 45%; p<0.001). Down syndrome, the most common genetic syndrome in the PPHNet Registry, constituted 11% of the entire PH cohort.

We find a striking proportion of paediatric PH patients with Group 3 disorders, reflecting the growing recognition of PH in diverse developmental lung diseases. Greater precision of clinical phenotyping based on disease-specific characterisation may further enhance care and research of paediatric PH.

关于肺动脉高压 (PH) 儿童的疾病范围、自然史、适合年龄的终点和最佳护理的数据有限，包括需要建立不同形式 PH 儿童的高质量患者登记册，以加强护理和研究。我们的目标是描述与儿科肺动脉高压相关的疾病的分布和临床特征，包括自然史、评估、治疗干预和结果，如世界肺动脉高压研讨会 (WSPH) 分类所定义。

1475 名患者被纳入小儿肺动脉高压网络 (PPHNet) 的多站点登记处，该网络由八个跨学科 PH 项目组成。

WSPH 第 1 组（肺动脉高压 (PAH)）和第 3 组（肺或缺氧相关 PH）是最常见的主要分类（分别为 45% 和 49% 的受试者）。最常见的第 3 组疾病是支气管肺发育不良和先天性膈疝。第 1 组疾病主要与先天性心脏病（第 1 组病例的 60%）和特发性 PAH（第 1 组病例的 23%）相关。与第 1 组相比，第 3 组受试者的疾病分辨率更好（风险比 3.1；p<0.001），诊断时往往更年轻（中位（四分位距）年龄 0.3 (0.0–0.6) 与 1.6 (0.1–6.9)岁） ；p<0.001）并且男性更常见（57%对比45%；p<0.001）。唐氏综合症是 PPHNet 登记中最常见的遗传综合症，占整个 PH 队列的 11%。

我们发现患有第 3 类疾病的儿科肺动脉高压患者的比例惊人，这反映出人们越来越认识到肺动脉高压在各种发育性肺疾病中的作用。基于疾病特异性特征的更精确的临床表型分析可能会进一步加强儿科 PH 的护理和研究。