Division of Clinical Epidemiology, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden.
Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
Paediatr Perinat Epidemiol. 2023 Sep;37(7):630-640. doi: 10.1111/ppe.12997. Epub 2023 Jul 6.
Preterm birth (<37 completed gestational weeks) has been linked to pulmonary hypertension (PH), but the relationship to severity of preterm birth has not been studied.
We investigated associations between extremely (<28 weeks), very (28-31 weeks), moderately (32-36 weeks) preterm birth, early-term birth (37-38 weeks) and later PH. Additionally, we explored associations between birthweight for gestational age and PH.
This registry-based cohort study followed 3.1 million individuals born in Sweden (1987-2016) from 1 up to a maximum of 30 years of age. The outcome was diagnosis or death from PH in national health registers. Adjusted hazard ratios (HR) were estimated using Cox regression analysis. Unadjusted and confounder-adjusted incidence rate differences were also calculated.
Of 3,142,812 individuals, there were 543 cases of PH (1.2 per 100,000 person-years), 153 of which in individuals without malformations. Compared with individuals born at 39 weeks, adjusted HRs with 95% confidence interval (CI) for PH for extremely, moderately, and very preterm birth were 68.78 (95% CI 49.49, 95.57), 13.86 (95% CI 9.27, 20.72) and 3.42 (95% CI 2.46, 4.74), respectively, and for early-term birth 1.74 (1.31, 2.32). HRs were higher in subjects without malformations. There were 90 additional cases of PH per 100,000 person-years in the extremely preterm group (50 after excluding malformations). Very small for gestational age (below 2 SD from estimated birthweight for gestational age and sex) was also associated with increased risk of PH (adjusted HR 2.02, 95% CI 1.14, 3.57).
We found an inverse association between gestational age and later PH, but the incidence and absolute risks are low. The severity of preterm birth adds clinically relevant information to the assessment of cardiovascular risks in childhood.
早产（<37 周完成妊娠）与肺动脉高压（PH）有关，但与早产严重程度的关系尚未研究。
我们研究了极早产（<28 周）、非常早产（28-31 周）、中度早产（32-36 周）、早期足月产（37-38 周）和晚期 PH 之间的关联。此外，我们还探讨了出生体重与 PH 的关系。
本基于登记的队列研究纳入了瑞典 1987 年至 2016 年期间出生的 3142812 人，随访时间长达 30 年。研究结局为国家健康登记中 PH 的诊断或死亡。采用 Cox 回归分析估计调整后的危险比（HR）。还计算了未调整和混杂因素调整后的发病率差异。
在 3142812 人中，有 543 例 PH（每 100000 人年 1.2 例），其中 153 例无畸形。与 39 周出生的个体相比，极早产、中度早产和非常早产的调整后 HR（95%CI）分别为 68.78（95%CI 49.49，95.57）、13.86（95%CI 9.27，20.72）和 3.42（95%CI 2.46，4.74），早期足月产为 1.74（95%CI 1.31，2.32）。无畸形者的 HR 更高。极早产组每 100000 人年多 90 例 PH（排除畸形后多 50 例）。小于胎龄儿（估计胎龄体重和性别低于 2 个标准差）也与 PH 风险增加相关（调整 HR 2.02，95%CI 1.14，3.57）。
我们发现胎龄与后期 PH 呈负相关，但发生率和绝对风险较低。早产的严重程度为儿童心血管风险评估提供了有临床意义的信息。
