Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
Obstetrics and Gynaecology Unit, Stockholm, Sweden.
Pediatr Allergy Immunol. 2023 Jan;34(1):e13904. doi: 10.1111/pai.13904.
Atopic dermatitis is a common chronic childhood disease associated with significant morbidity and healthcare costs. There is a known association between caesarean section and asthma, but the relationship between caesarean section and offspring atopic dermatitis remains uncertain.
We conducted a register-based nationwide cohort study including children born in Sweden between January 2006 and December 2018. Data on health and socioeconomic variables were extracted from the national registers for children aged ≤5 years. Time-to-event analyses were used to calculate hazard ratios (HR) with 95% confidence intervals (CI) adjusting for confounders and familial factors.
1,399,406 children were included (6,029,542 person-years at risk). Atopic dermatitis was observed in 17.2% of the 1,150,896 children born by vaginal delivery and 18.3% of the 248,510 born by caesarean section. The mean age of onset of atopic dermatitis was 2.72 years (SD 1.8). Birth by caesarean section was associated with a higher risk of atopic dermatitis (adj-HR 1.12, 95% CI: 1.10-1.14). A higher risk of atopic dermatitis was found in children born by instrumental vaginal delivery (adj-HR 1.10, 1.07-1.13); emergency caesarean section (adj-HR 1.12, 1.10-1.15), and elective caesarean section (adj-HR 1.13, 1.10-1.16) than uncomplicated vaginal delivery in children <1 year of age. Similar hazards were observed in those ≥1 year of age. In sibling control analysis, greater risks remained in children aged <1 year but not in age ≥1 year.
In our study population, it was observed that children born by caesarean section or instrumental vaginal delivery were at higher risk of early childhood atopic dermatitis. Although familial confounding attenuates the risk in children aged ≥1 year, this was not observed in the first year of life.
特应性皮炎是一种常见的儿童慢性疾病，与显著的发病率和医疗保健费用有关。剖宫产与哮喘之间存在已知的关联，但剖宫产与后代特应性皮炎之间的关系仍不确定。
我们进行了一项基于登记的全国性队列研究，纳入了 2006 年 1 月至 2018 年 12 月期间在瑞典出生的儿童。从儿童国家登记处提取了健康和社会经济变量的数据，年龄在 5 岁及以下。使用时间事件分析来计算调整混杂因素和家族因素后的风险比（HR）及其 95%置信区间（CI）。
共纳入 1399406 名儿童（6029542 人年风险）。阴道分娩出生的 1150896 名儿童中有 17.2%患有特应性皮炎，剖宫产出生的 248510 名儿童中有 18.3%患有特应性皮炎。特应性皮炎的平均发病年龄为 2.72 岁（标准差 1.8）。剖宫产出生与特应性皮炎风险增加相关（调整 HR 1.12，95%CI：1.10-1.14）。经阴道器械分娩（调整 HR 1.10，1.07-1.13）、急症剖宫产（调整 HR 1.12，1.10-1.15）和择期剖宫产（调整 HR 1.13，1.10-1.16）出生的儿童比未经产道分娩的儿童（年龄<1 岁）患特应性皮炎的风险更高。在年龄≥1 岁的儿童中也观察到类似的危险。在同胞对照分析中，年龄<1 岁的儿童风险增加，但年龄≥1 岁的儿童则没有。
在本研究人群中，观察到剖宫产或经阴道器械分娩的儿童患早期儿童特应性皮炎的风险较高。虽然家族性混杂因素会降低年龄≥1 岁儿童的风险，但在生命的第一年没有观察到这种情况。
