美国布列根和妇女医院和哈佛医学院Eva S Schernhammer小组研究了出生月份、出生季节与美国女性的总死亡率和心血管疾病死亡率的关系。2019年12月18日，国际知名学术期刊《英国医学杂志》发表了这一成果。

为评价出生月份、出生季节与美国女性总死亡率和心血管疾病死亡率之间的关系，探讨家庭和社会经济因素在其中的作用，研究组在1976年建立护士健康研究，以进行前瞻性队列研究。参与者为116911名女护士，在1976-2014年间注册，均有详细的出生日期信息。

经过38年，研究组共随访了4136364人年，期间有43248例参与者死亡，包括8360例心血管疾病相关死亡。在校正的多变量分析中，未观察到出生月份、出生季节和总死亡率之间的显著相关性。

与11月份出生的女性相比，3-7月份出生的女性心血管疾病死亡率增加。4月份出生的女性心血管疾病死亡率最高，12月份最低，相对差异为17.89%。春季和夏季出生的女性心血管死亡率显著高于秋季。对家庭和社会经济因素校正后，该结果不变。最低和最高危险季节的相对差异为10%。

总之，春夏季（尤其是3-7月份）出生的女性心血管特异性死亡率有所上升。但出生季节对女性总死亡率无影响。仍需进一步研究来揭示出生季节影响心血管疾病死亡率的机制。

附：英文原文

Title: Birth month, birth season, and overall and cardiovascular disease mortality in US women: prospective cohort study

Author: Yin Zhang, Elizabeth E Devore, Susanne Strohmaier, Francine Grodstein, Eva S Schernhammer

Issue&Volume: 2019/12/18

Abstract: 

Objectives To evaluate the associations between birth month, birth season, and overall and cardiovascular disease mortality, and to examine the role of familial and socioeconomic factors in these associations.

Design Prospective cohort study.

Setting Nurses’ Health Study, established in 1976, an ongoing prospective cohort study in the United States.

Participants Female registered nurses who reported information on date of birth at study enrolment (n=116 911, 1976-2014, followed for 38 years).

Exposure Birth month and astronomical birth season (based on solstices and equinoxes as boundaries of the season categories).

Main outcome measures Age and various multivariable adjusted hazard ratios and 95% confidence intervals for the association between birth months (using November as the reference), astronomical birth season (using autumn as the reference), and overall and cardiovascular disease specific mortality were assessed using Cox proportional hazards models.

Results Among study participants, 43 248 overall deaths were documented during 4 136 364 person years of follow-up since enrolment, including 8360 cardiovascular disease related deaths. In fully adjusted multivariable analyses, no significant association was observed between birth month, birth season, and overall mortality. Compared with women born in November, increased cardiovascular disease mortality was observed among those born from March to July (hazard ratio for March, 1.09, 95% confidence interval 0.98 to 1.21; April, 1.12, 1.00 to 1.24; May, 1.08, 0.98 to 1.20; June, 1.07, 0.96 to 1.19; and July 1.08, 0.98 to 1.20). Those born in April had the highest cardiovascular disease mortality, and those born in December had the lowest (December, 0.95, 0.85 to 1.06). The relative difference between the lowest and highest risk month was 17.89%. Women born in spring (1.10, 1.04 to 1.17) and summer (1.09, 1.03 to 1.16) had a higher cardiovascular disease mortality than women born in the autumn. Adjustment for familial and socioeconomic factors did not change these results. The relative difference between the lowest and highest risk season was 10.00%.

Conclusion Participants born in the spring and summer (especially those born in March-July) had a slight but significant increase in cardiovascular disease specific mortality. However, no seasonal birth month effect was observed among women for overall mortality. Familial and socioeconomic factors did not appear to alter these associations. Further studies are required to confirm these findings and reveal mechanisms of these seasonal birth month effects in cardiovascular disease mortality.

DOI: 10.1136/bmj.l6058

Source: https://www.bmj.com/content/367/bmj.l6058