Douglas A S, Helms P J, Jolliffe I T
University Dept. of Medicine and Therapeutics, University of Aberdeen, UK.
Eur Respir J. 1999 Jan;13(1):95-9. doi: 10.1183/09031936.99.13109599.
This study aimed to investigate whether seasonal variation in day length contributed to winter/summer variation in sudden infant death syndrome (SIDS) at different latitudes in mainland Britain. Over 11 yrs 13,973 deaths were studied. Using appropriate analytic techniques a sine curve was fitted to monthly rates with the amplitude indicating magnitude of seasonal change. The rate of SIDS per 1,000 live births was the same (1.73) in the north as in the south. The amplitude was a quarter less in the north (41.3%) than in the south (54.2%) (p<0.001). While annual rates did not differ, the within year distribution did. The findings for seasonality of SIDS births were similar (amplitudes: north 213%, south 32.3%). Correlations were made between SIDS amplitude and individual environmental factors, particularly temperature and day length. These complex issues, while reported briefly, do not allow firm conclusions. In the north the winter day length is shorter, sunshine hours are less and temperature is lower, but the winter increment in SIDS is less. The extent of seasonal variation of sudden infant death syndrome is greater in the south as compared with the colder, darker north but this has no effect on sudden infant death syndrome rates. Changing photoperiod by latitude, amongst other environmental influences, may hold clues to the aetiology of sudden infant death syndrome.
本研究旨在调查白昼时长的季节性变化是否导致了英国大陆不同纬度地区婴儿猝死综合征（SIDS）的冬夏差异。在11年多的时间里，对13973例死亡病例进行了研究。运用适当的分析技术，将一条正弦曲线拟合到月发生率上，其振幅表明季节性变化的幅度。每1000例活产婴儿的SIDS发生率在北方和南方相同（均为1.73）。北方的振幅比南方小四分之一（北方为41.3%，南方为54.2%）（p<0.001）。虽然年发生率没有差异，但年内分布情况有所不同。SIDS出生的季节性研究结果相似（振幅：北方21.3%，南方32.3%）。对SIDS振幅与个体环境因素，尤其是温度和白昼时长之间进行了相关性分析。这些复杂问题虽已简要报告，但无法得出确凿结论。在北方，冬季白昼较短，日照时间较少，温度较低，但SIDS在冬季的增幅较小。与寒冷、阴暗的北方相比，婴儿猝死综合征的季节性变化程度在南方更大，但这对婴儿猝死综合征发生率没有影响。除其他环境影响外，纬度导致的光周期变化可能为婴儿猝死综合征的病因提供线索。
