Skip to main content
Archives of Disease in Childhood logoLink to Archives of Disease in Childhood
. 2004 Mar;89(3):267–271. doi: 10.1136/adc.2002.025486

A multivariate "time based" analysis of SIDS risk factors

T Matthews 1, M McDonnell 1, C McGarvey 1, G Loftus 1, M O'Regan 1
PMCID: PMC1719812  PMID: 14977707

Abstract

Aims: To investigate the influence of analytical design on the variability of published results in studies of sudden infant death syndrome (SIDS).

Methods: The results of a prospective case-control study, of 203 cases of SIDS, and 622 control infants are presented. All variables significant on univariate analysis were included in a multivariate model analysed in nine stages, starting with sociodemographic variables, then sequentially and cumulatively adding variables relating to pregnancy history, current pregnancy, birth, the interval from birth to the week prior to death, the last week, the last 48 hours, and the last sleep period. A ninth stage was created by adding placed to sleep prone for the last sleep period.

Results: As additional variables are added, previously published SIDS risk factors emerged such as social deprivation, young maternal age, ⩾3 previous live births, maternal smoking and drinking, urinary tract infection in pregnancy, reduced birth weight, and the infant having an illness, regurgitation, being sweaty, or a history of crying/colic in the interval from birth to the week before death, with co-sleeping and the lack of regular soother use important in the last sleep period. As the model progressed through stages 1–9, many significant variables became non-significant (social deprivation, young maternal age, maternal smoking and drinking) and in stage 9 the addition of placed to sleep prone for the last sleep period caused ⩾3 previous live births and a reduced birth weight to become significant.

Conclusion: The variables found to be significant in a case-control study, depend on what is included in a multivariate model.

Full Text

The Full Text of this article is available as a PDF (163.2 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Alm B., Wennergren G., Norvenius G., Skjaerven R., Oyen N., Helweg-Larsen K., Lagercrantz H., Irgens L. M. Caffeine and alcohol as risk factors for sudden infant death syndrome. Nordic Epidemiological SIDS Study. Arch Dis Child. 1999 Aug;81(2):107–111. doi: 10.1136/adc.81.2.107. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Blair P. S., Fleming P. J., Bensley D., Smith I., Bacon C., Taylor E., Berry J., Golding J., Tripp J. Smoking and the sudden infant death syndrome: results from 1993-5 case-control study for confidential inquiry into stillbirths and deaths in infancy. Confidential Enquiry into Stillbirths and Deaths Regional Coordinators and Researchers. BMJ. 1996 Jul 27;313(7051):195–198. doi: 10.1136/bmj.313.7051.195. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Brooke H., Gibson A., Tappin D., Brown H. Case-control study of sudden infant death syndrome in Scotland, 1992-5. BMJ. 1997 May 24;314(7093):1516–1520. doi: 10.1136/bmj.314.7093.1516. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Carpenter R. G., Gardner A., McWeeny P. M., Emery J. L. Multistage scoring system for identifying infants at risk of unexpected death. Arch Dis Child. 1977 Aug;52(8):606–612. doi: 10.1136/adc.52.8.606. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Dwyer T., Couper D., Walter S. D. Sources of heterogeneity in the meta-analysis of observational studies: the example of SIDS and sleeping position. J Clin Epidemiol. 2001 May;54(5):440–447. doi: 10.1016/s0895-4356(00)00313-9. [DOI] [PubMed] [Google Scholar]
  6. Dwyer T., Ponsonby A. L. The decline of SIDS: a success story for epidemiology. Epidemiology. 1996 May;7(3):323–325. [PubMed] [Google Scholar]
  7. Gilbert R., Rudd P., Berry P. J., Fleming P. J., Hall E., White D. G., Oreffo V. O., James P., Evans J. A. Combined effect of infection and heavy wrapping on the risk of sudden unexpected infant death. Arch Dis Child. 1992 Feb;67(2):171–177. doi: 10.1136/adc.67.2.171. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Hoffman H. J., Damus K., Hillman L., Krongrad E. Risk factors for SIDS. Results of the National Institute of Child Health and Human Development SIDS Cooperative Epidemiological Study. Ann N Y Acad Sci. 1988;533:13–30. doi: 10.1111/j.1749-6632.1988.tb37230.x. [DOI] [PubMed] [Google Scholar]
  9. Kinney H. C., Brody B. A., Finkelstein D. M., Vawter G. F., Mandell F., Gilles F. H. Delayed central nervous system myelination in the sudden infant death syndrome. J Neuropathol Exp Neurol. 1991 Jan;50(1):29–48. doi: 10.1097/00005072-199101000-00003. [DOI] [PubMed] [Google Scholar]
  10. Kraus J. F., Greenland S., Bulterys M. Risk factors for sudden infant death syndrome in the US Collaborative Perinatal Project. Int J Epidemiol. 1989 Mar;18(1):113–120. doi: 10.1093/ije/18.1.113. [DOI] [PubMed] [Google Scholar]
  11. Leviton A., Paneth N., Reuss M. L., Susser M., Allred E. N., Dammann O., Kuban K., Van Marter L. J., Pagano M., Hegyi T. Maternal infection, fetal inflammatory response, and brain damage in very low birth weight infants. Developmental Epidemiology Network Investigators. Pediatr Res. 1999 Nov;46(5):566–575. doi: 10.1203/00006450-199911000-00013. [DOI] [PubMed] [Google Scholar]
  12. Mehanni M., Cullen A., Kiberd B., McDonnell M., O'Regan M., Matthews T. The current epidemiology of SIDS in Ireland. Ir Med J. 2000 Dec;93(9):264–268. [PubMed] [Google Scholar]
  13. Mitchell E. A., Tuohy P. G., Brunt J. M., Thompson J. M., Clements M. S., Stewart A. W., Ford R. P., Taylor B. J. Risk factors for sudden infant death syndrome following the prevention campaign in New Zealand: a prospective study. Pediatrics. 1997 Nov;100(5):835–840. doi: 10.1542/peds.100.5.835. [DOI] [PubMed] [Google Scholar]
  14. Ponsonby A. L., Dwyer T., Gibbons L. E., Cochrane J. A., Wang Y. G. Factors potentiating the risk of sudden infant death syndrome associated with the prone position. N Engl J Med. 1993 Aug 5;329(6):377–382. doi: 10.1056/NEJM199308053290601. [DOI] [PubMed] [Google Scholar]
  15. Schieve L. A., Handler A., Hershow R., Persky V., Davis F. Urinary tract infection during pregnancy: its association with maternal morbidity and perinatal outcome. Am J Public Health. 1994 Mar;84(3):405–410. doi: 10.2105/ajph.84.3.405. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Tin W., Wariyar U. K., Hey E. N. Selection biases invalidate current low birthweight weight-for-gestation standards. The Northern Neonatal Network. Br J Obstet Gynaecol. 1997 Feb;104(2):180–185. doi: 10.1111/j.1471-0528.1997.tb11041.x. [DOI] [PubMed] [Google Scholar]
  17. Wennergren G., Alm B., Oyen N., Helweg-Larsen K., Milerad J., Skjaerven R., Norvenius S. G., Lagercrantz H., Wennborg M., Daltveit A. K. The decline in the incidence of SIDS in Scandinavia and its relation to risk-intervention campaigns. Nordic Epidemiological SIDS Study. Acta Paediatr. 1997 Sep;86(9):963–968. doi: 10.1111/j.1651-2227.1997.tb15180.x. [DOI] [PubMed] [Google Scholar]
  18. l'Hoir M. P., Engelberts A. C., van Well G. T., Westers P., Mellenbergh G. J., Wolters W. H., Huber J. Case-control study of current validity of previously described risk factors for SIDS in The Netherlands. Arch Dis Child. 1998 Nov;79(5):386–393. doi: 10.1136/adc.79.5.386. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Archives of Disease in Childhood are provided here courtesy of BMJ Publishing Group

RESOURCES