Braun School of Public Health and Community Medicine, Hebrew University of Jerusalem Faculty of Medicine, Jerusalem, Israel
Braun School of Public Health and Community Medicine, Hebrew University of Jerusalem Faculty of Medicine, Jerusalem, Israel.
J Epidemiol Community Health. 2020 Nov;74(11):957-963. doi: 10.1136/jech-2020-214242. Epub 2020 Jul 12.
Scarce research is available regarding the association between interbirth intervals (IBI) and long-term maternal health outcomes, particularly cardiovascular disease (CVD) mortality. We aimed to assess whether IBIs were associated with all-cause, CVD-related and cancer-related mortality.
We conducted a cohort study in the setting of the Jerusalem Perinatal Study. Women with at least two consecutive singleton live births in 1964-1976 (N=18 294) were followed through 2016. IBIs were calculated as the interval between women's first and second cohort birth. We estimated associations between IBIs and mortality using Cox's proportional hazards models, adjusting for age, parity, maternal education, maternal origin and paternal socioeconomic status. Date of last menstrual period was available for a subset of women. We assessed the interpregnancy interval (IPI) for these women and compared the models using IPI and IBI.
During 868 079 years of follow up (median follow-up: 49.0 years), 3337 women died. Women with IBIs <15 months had higher all-cause mortality rates (HR 1.18; 95% CI 1.05 to 1.33) compared to women with 33-month to 68-month IBIs (reference category). IBI and CVD mortality appeared to have a J-shaped association; IBIs of <15, 15-20, 21-2626-2632, 33-68 and ≥69 months had HRs of 1.44, 1.40, 1.33, 1.14, 1.00 and 1.30, respectively. No substantial association was found with cancer mortality. Models using IPIs and those using IBI were similar.
Our results support the WHO recommendations for IPIs of ≥24 months and add additional evidence regarding long-term CVD mortality.
关于出生间隔（IBI）与长期产妇健康结局之间的关联，尤其是心血管疾病（CVD）死亡率，相关研究较少。我们旨在评估 IBI 是否与全因、CVD 相关和癌症相关死亡率相关。
我们在耶路撒冷围产研究中进行了一项队列研究。1964 年至 1976 年期间至少有两次连续单胎活产的女性（N=18294）被随访至 2016 年。IBI 计算为女性首次和第二次队列分娩之间的间隔。我们使用 Cox 比例风险模型估计 IBI 与死亡率之间的关联，调整了年龄、产次、母亲教育、母亲原籍国和父亲社会经济地位。对于部分女性，我们可以获得末次月经日期。我们评估了这些女性的孕中期间隔（IPI），并比较了使用 IPI 和 IBI 的模型。
在 868079 年的随访期间（中位随访时间：49.0 年），有 3337 名女性死亡。与 33 个月至 68 个月 IBI （参考类别）相比，IBI<15 个月的女性全因死亡率更高（HR 1.18；95%CI 1.05 至 1.33）。IBI 和 CVD 死亡率似乎呈 J 形关联；IBI<15、15-20、21-26、26-32、33-68 和≥69 个月的 HR 分别为 1.44、1.40、1.33、1.14、1.00 和 1.30。与癌症死亡率无明显关联。使用 IPI 的模型和使用 IBI 的模型相似。
我们的研究结果支持世界卫生组织关于 IPI 至少为 24 个月的建议，并提供了关于长期 CVD 死亡率的额外证据。
