Skip to main navigation menu Skip to main content Skip to site footer
##common.pageHeaderLogo.altText##

Original article

Vol. 154 No. 11 (2024)

Sociodemographic and regional differences in neonatal and infant mortality in Switzerland in 2011–2018: the Swiss National Cohort

DOI
https://doi.org/10.57187/s.3682
Cite this as:
Swiss Med Wkly. 2024;154:3682
Published
28.11.2024

Summary

BACKGROUND AND AIMS: Despite a well-funded healthcare system with universal insurance coverage, Switzerland has one of the highest neonatal and infant mortality rates among high-income countries. Identifying avoidable risk factors targeted by evidence-based policies is a public health priority. We describe neonatal and infant mortality in Switzerland from 2011 to 2018 and explore associations with neonatal- and pregnancy-related variables, parental sociodemographic information, regional factors and socioeconomic position (SEP) using data from a long-term nationwide cohort study.

METHODS: We included 680,077 live births, representing 99.3% of all infants born in Switzerland between January 2011 and December 2018. We deterministically linked the national live birth register with the mortality register and with census and survey data to create a longitudinal dataset of neonatal- and pregnancy-related variables; parental sociodemographic information, such as civil status, age, religion, education, nationality; regional factors, such as urbanity, language region; and the Swiss neighbourhood index of socioeconomic position (Swiss-SEP index). Information on maternal education was available for a random subset of 242,949 infants. We investigated associations with neonatal and infant mortality by fitting multivariable Poisson regression models with robust standard errors. Several sensitivity analyses assessed the robustness of our findings.

RESULTS: Overall, neonatal mortality rates between 2011 and 2018 were 3.0 per 1000 live births, with regional variations: 3.2 in German-speaking, 2.4 in French-speaking and 2.1 in Italian-speaking Switzerland. For infant mortality, the rates were 3.7 per 1000 live births overall, and 3.9 in the German-speaking, 3.3 in the French-speaking and 2.9 in the Italian-speaking region. After adjusting for sex, maternal age, multiple birth and birth rank, neonatal mortality remained significantly associated with language region (adjusted rate ratio [aRR] 0.72, 95% confidence interval [CI]: 0.64–0.80 for the French-speaking region and aRR 0.66, 95% CI: 0.51–0.87 for the Italian-speaking region vs German-speaking region), with marital status (aRR 1.55, 95% CI: 1.40–1.71 for unmarried vs married), nationality (aRR 1.40, 95% CI: 1.21–1.62 for non-European Economic Area vs Swiss) and the Swiss-SEP index (aRR 1.17, 95% CI: 1.00–1.36 for lowest vs highest SEP quintile). In the subset, we showed a possible association of neonatal mortality with maternal education (aRR 1.24, 95% CI: 0.95–1.61 for compulsory vs tertiary education).

CONCLUSION: We provide detailed evidence about the social patterning of neonatal and infant mortality in Switzerland and reveal important regional differences with about 30% lower risks in French- and Italian-speaking compared with German-speaking regions. Underlying causes for such regional differences, such as cultural, lifestyle or healthcare-related factors, warrant further exploration to inform and provide an evidence base for public health policies.

References

  1. Paulson KR, Kamath AM, Alam T, Bienhoff K, Abady GG, Abbas J, et al.; GBD 2019 Under-5 Mortality Collaborators. Global, regional, and national progress towards Sustainable Development Goal 3.2 for neonatal and child health: all-cause and cause-specific mortality findings from the Global Burden of Disease Study 2019. Lancet. 2021 Sep;398(10303):870–905. doi: https://doi.org/10.1016/S0140-6736(21)01207-1 DOI: https://doi.org/10.1016/S0140-6736(21)01207-1
  2. World Health Organization Global Health Expenditure Database. Available from: https://apps.who.int/nha/database/Country_Profile/Index/en
  3. World Health Organization Life expectancy and Healthy life expectancy. Available from: https://apps.who.int/gho/data/node.main.688
  4. Skrivankova V, Zwahlen M, Adams M, Low N, Kuehni C, Egger M. Spatial epidemiology of gestational age and birth weight in Switzerland: census-based linkage study. BMJ Open. 2019 Oct;9(10):e027834. doi: https://doi.org/10.1136/bmjopen-2018-027834 DOI: https://doi.org/10.1136/bmjopen-2018-027834
  5. Wanner P. Adverse perinatal outcomes among children in Switzerland: the impact of national origin and socio-economic group. Int J Public Health. 2020 Dec;65(9):1613–21. doi: https://doi.org/10.1007/s00038-020-01492-2 DOI: https://doi.org/10.1007/s00038-020-01492-2
  6. Wanner P, Bollini P. The contribution of the foreign population to the high level of infant mortality in Switzerland: a demographic analysis. BMC Pregnancy Childbirth. 2017 May;17(1):151. doi: https://doi.org/10.1186/s12884-017-1332-6 DOI: https://doi.org/10.1186/s12884-017-1332-6
  7. Bopp M, Spoerri A, Zwahlen M, Gutzwiller F, Paccaud F, Braun-Fahrländer C, et al. Cohort Profile: the Swiss National Cohort—a longitudinal study of 6.8 million people. Int J Epidemiol. 2009 Apr;38(2):379–84. doi: https://doi.org/10.1093/ije/dyn042 DOI: https://doi.org/10.1093/ije/dyn042
  8. Spoerri A, Zwahlen M, Egger M, Bopp M. The Swiss National Cohort: a unique database for national and international researchers. Int J Public Health. 2010 Aug;55(4):239–42. doi: https://doi.org/10.1007/s00038-010-0160-5 DOI: https://doi.org/10.1007/s00038-010-0160-5
  9. Devlieger H, Martens G, Bekaert A. Social inequalities in perinatal and infant mortality in the northern region of Belgium (the Flanders). Eur J Public Health. 2005 Feb;15(1):15–9. doi: https://doi.org/10.1093/eurpub/cki104 DOI: https://doi.org/10.1093/eurpub/cki104
  10. Dallolio L, Di Gregori V, Lenzi J, Franchino G, Calugi S, Domenighetti G, et al. Socio-economic factors associated with infant mortality in Italy: an ecological study. Int J Equity Health. 2012 Aug;11(1):45. doi: https://doi.org/10.1186/1475-9276-11-45 DOI: https://doi.org/10.1186/1475-9276-11-45
  11. Luque-Fernandez MA, Thomas A, Gelaye B, Racape J, Sanchez MJ, Williams MA. Secular trends in stillbirth by maternal socioeconomic status in Spain 2007-15: a population-based study of 4 million births. Eur J Public Health. 2019 Dec;29(6):1043–8. doi: https://doi.org/10.1093/eurpub/ckz086 DOI: https://doi.org/10.1093/eurpub/ckz086
  12. Tromp M, Eskes M, Reitsma JB, Erwich JJ, Brouwers HA, Rijninks-van Driel GC, et al. Regional perinatal mortality differences in the Netherlands; care is the question. BMC Public Health. 2009 Apr;9(1):102. doi: https://doi.org/10.1186/1471-2458-9-102 DOI: https://doi.org/10.1186/1471-2458-9-102
  13. Gilbert NL, Auger N, Wilkins R, Kramer MS. Neighbourhood income and neonatal, postneonatal and sudden infant death syndrome (SIDS) mortality in Canada, 1991-2005. Can J Public Health. 2013 Mar;104(3):e187–92. doi: https://doi.org/10.17269/cjph.104.3739 DOI: https://doi.org/10.17269/cjph.104.3739
  14. Panczak R, Galobardes B, Voorpostel M, Spoerri A, Zwahlen M, Egger M; Swiss National Cohort and Swiss Household Panel. A Swiss neighbourhood index of socioeconomic position: development and association with mortality. J Epidemiol Community Health. 2012 Dec;66(12):1129–36. doi: https://doi.org/10.1136/jech-2011-200699 DOI: https://doi.org/10.1136/jech-2011-200699
  15. Zou G. A modified poisson regression approach to prospective studies with binary data. Am J Epidemiol. 2004 Apr;159(7):702–6. doi: https://doi.org/10.1093/aje/kwh090 DOI: https://doi.org/10.1093/aje/kwh090
  16. Cole SR, Hernán MA. Fallibility in estimating direct effects. Int J Epidemiol. 2002 Feb;31(1):163–5. doi: https://doi.org/10.1093/ije/31.1.163 DOI: https://doi.org/10.1093/ije/31.1.163
  17. Hernán MA, Hernández-Díaz S, Werler MM, Mitchell AA. Causal knowledge as a prerequisite for confounding evaluation: an application to birth defects epidemiology. Am J Epidemiol. 2002 Jan;155(2):176–84. doi: https://doi.org/10.1093/aje/155.2.176 DOI: https://doi.org/10.1093/aje/155.2.176
  18. Wilcox AJ, Weinberg CR, Basso O. On the pitfalls of adjusting for gestational age at birth. Am J Epidemiol. 2011 Nov;174(9):1062–8. doi: https://doi.org/10.1093/aje/kwr230 DOI: https://doi.org/10.1093/aje/kwr230
  19. R Core Team. (2021). R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria.; Available from: https://www.R-project.org/
  20. Wilcox AJ. On the importance—and the unimportance—of birthweight. Int J Epidemiol. 2001 Dec;30(6):1233–41. doi: https://doi.org/10.1093/ije/30.6.1233 DOI: https://doi.org/10.1093/ije/30.6.1233
  21. Hernández-Díaz S, Schisterman EF, Hernán MA. The birth weight “paradox” uncovered? Am J Epidemiol. 2006 Dec;164(11):1115–20. doi: https://doi.org/10.1093/aje/kwj275 DOI: https://doi.org/10.1093/aje/kwj275
  22. Hernández-Díaz S, Wilcox AJ, Schisterman EF, Hernán MA. From causal diagrams to birth weight-specific curves of infant mortality. Eur J Epidemiol. 2008;23(3):163–6. doi: https://doi.org/10.1007/s10654-007-9220-4 DOI: https://doi.org/10.1007/s10654-007-9220-4
  23. Neophytou AM, Kioumourtzoglou MA, Goin DE, Darwin KC, Casey JA. Educational note: addressing special cases of bias that frequently occur in perinatal epidemiology. Int J Epidemiol. 2021 Mar;50(1):337–45. doi: https://doi.org/10.1093/ije/dyaa252 DOI: https://doi.org/10.1093/ije/dyaa252
  24. Balaj M, York HW, Sripada K, Besnier E, Vonen HD, Aravkin A, et al. Parental education and inequalities in child mortality: a global systematic review and meta-analysis. Lancet. 2021 Aug;398(10300):608–20. doi: https://doi.org/10.1016/S0140-6736(21)00534-1 DOI: https://doi.org/10.1016/S0140-6736(21)00534-1
  25. Liew Z, Olsen J, Cui X, Ritz B, Arah OA. Bias from conditioning on live birth in pregnancy cohorts: an illustration based on neurodevelopment in children after prenatal exposure to organic pollutants. Int J Epidemiol. 2015 Feb;44(1):345–54. doi: https://doi.org/10.1093/ije/dyu249 DOI: https://doi.org/10.1093/ije/dyu249
  26. Schwangerschaften und Geburten unter schwierigen Bedingungen. 2022, Neuchâtel: Bundesamt für Statistik (BFS). 12. Available from: https://www.swissstats.bfs.admin.ch/collection/ch.admin.bfs.swissstat.de.issue22012382201/article/issue22012382201-01
  27. Totgeburten und Säuglingssterblichkeit 2003-2010. 2012, Neuchâtel: Bundesamt für Statistik (BFS). Available from: https://www.admin.ch/gov/de/start/dokumentation/medienmitteilungen.msg-id-43824.html
  28. Bollini P, Stotzer U, Wanner P. Pregnancy outcomes and migration in Switzerland: results from a focus group study. Int J Public Health. 2007;52(2):78–86. doi: https://doi.org/10.1007/s00038-007-6003-3 DOI: https://doi.org/10.1007/s00038-007-6003-3
  29. Thomson K, Moffat M, Arisa O, Jesurasa A, Richmond C, Odeniyi A, et al. Socioeconomic inequalities and adverse pregnancy outcomes in the UK and Republic of Ireland: a systematic review and meta-analysis. BMJ Open. 2021 Mar;11(3):e042753. doi: https://doi.org/10.1136/bmjopen-2020-042753 DOI: https://doi.org/10.1136/bmjopen-2020-042753
  30. Best KE, Seaton SE, Draper ES, Field DJ, Kurinczuk JJ, Manktelow BN, et al. Assessing the deprivation gap in stillbirths and neonatal deaths by cause of death: a national population-based study. Arch Dis Child Fetal Neonatal Ed. 2019 Nov;104(6):F624–30. doi: https://doi.org/10.1136/archdischild-2018-316124 DOI: https://doi.org/10.1136/archdischild-2018-316124
  31. Kroll ME, Kurinczuk JJ, Hollowell J, Macfarlane A, Li Y, Quigley MA. Ethnic and socioeconomic variation in cause-specific preterm infant mortality by gestational age at birth: national cohort study. Arch Dis Child Fetal Neonatal Ed. 2020 Jan;105(1):56–63. doi: https://doi.org/10.1136/archdischild-2018-316463 DOI: https://doi.org/10.1136/archdischild-2018-316463
  32. Zylbersztejn A, Gilbert R, Hjern A, Wijlaars L, Hardelid P. Child mortality in England compared with Sweden: a birth cohort study. Lancet. 2018 May;391(10134):2008–18. doi: https://doi.org/10.1016/S0140-6736(18)30670-6 DOI: https://doi.org/10.1016/S0140-6736(18)30670-6
  33. El-Sayed AM, Finkton DW Jr, Paczkowski M, Keyes KM, Galea S. Socioeconomic position, health behaviors, and racial disparities in cause-specific infant mortality in Michigan, USA. Prev Med. 2015 Jul;76:8–13. doi: https://doi.org/10.1016/j.ypmed.2015.03.021 DOI: https://doi.org/10.1016/j.ypmed.2015.03.021
  34. Luque-Fernández MÁ, Lone NI, Gutiérrez-Garitano I, Bueno-Cavanillas A. Stillbirth risk by maternal socio-economic status and country of origin: a population-based observational study in Spain, 2007-08. Eur J Public Health. 2012 Aug;22(4):524–9. doi: https://doi.org/10.1093/eurpub/ckr074 DOI: https://doi.org/10.1093/eurpub/ckr074
  35. Bertens LC, Burgos Ochoa L, Van Ourti T, Steegers EA, Been JV. Persisting inequalities in birth outcomes related to neighbourhood deprivation. J Epidemiol Community Health. 2020 Mar;74(3):232–9. doi: https://doi.org/10.1136/jech-2019-213162 DOI: https://doi.org/10.1136/jech-2019-213162
  36. Burgos Ochoa L, Bertens LC, Garcia-Gomez P, Van Ourti T, Steegers EA, Been JV. Association of neighbourhood socioeconomic trajectories with preterm birth and small-for-gestational-age in the Netherlands: a nationwide population-based study. Lancet Reg Health Eur. 2021 Aug;10:100205. doi: https://doi.org/10.1016/j.lanepe.2021.100205 DOI: https://doi.org/10.1016/j.lanepe.2021.100205
  37. Vidiella-Martin J, Been JV, Van Doorslaer E, García-Gómez P, Van Ourti T; Association Between Income and Perinatal Mortality in the Netherlands Across Gestational Age. Association Between Income and Perinatal Mortality in the Netherlands Across Gestational Age. JAMA Netw Open. 2021 Nov;4(11):e2132124. doi: https://doi.org/10.1001/jamanetworkopen.2021.32124 DOI: https://doi.org/10.1001/jamanetworkopen.2021.32124
  38. Vos AA, Denktaş S, Borsboom GJ, Bonsel GJ, Steegers EA. Differences in perinatal morbidity and mortality on the neighbourhood level in Dutch municipalities: a population based cohort study. BMC Pregnancy Childbirth. 2015 Sep;15(1):201. doi: https://doi.org/10.1186/s12884-015-0628-7 DOI: https://doi.org/10.1186/s12884-015-0628-7
  39. Dallolio L, Lenzi J, Fantini MP. Temporal and geographical trends in infant, neonatal and post-neonatal mortality in Italy between 1991 and 2009. Ital J Pediatr. 2013 Mar;39(1):19. doi: https://doi.org/10.1186/1824-7288-39-19 DOI: https://doi.org/10.1186/1824-7288-39-19
  40. Simeoni S, Frova L, De Curtis M. Inequalities in infant mortality in Italy. Ital J Pediatr. 2019 Jan;45(1):11. doi: https://doi.org/10.1186/s13052-018-0594-6 DOI: https://doi.org/10.1186/s13052-018-0594-6
  41. Miao Q, Dunn S, Wen SW, Lougheed J, Reszel J, Lavin Venegas C, et al. Neighbourhood maternal socioeconomic status indicators and risk of congenital heart disease. BMC Pregnancy Childbirth. 2021 Jan;21(1):72. doi: https://doi.org/10.1186/s12884-020-03512-8 DOI: https://doi.org/10.1186/s12884-020-03512-8
  42. Pestoni G, Krieger JP, Sych JM, Faeh D, Rohrmann S. Cultural Differences in Diet and Determinants of Diet Quality in Switzerland: Results from the National Nutrition Survey menuCH. Nutrients. 2019 Jan;11(1):126. doi: https://doi.org/10.3390/nu11010126 DOI: https://doi.org/10.3390/nu11010126
  43. Wanner M, Probst-Hensch N, Kriemler S, Meier F, Autenrieth C, Martin BW. Validation of the long international physical activity questionnaire: influence of age and language region. Prev Med Rep. 2016 Mar;3:250–6. doi: https://doi.org/10.1016/j.pmedr.2016.03.003 DOI: https://doi.org/10.1016/j.pmedr.2016.03.003
  44. Roser K, Mader L, Baenziger J, Sommer G, Kuehni CE, Michel G. Health-related quality of life in Switzerland: normative data for the SF-36v2 questionnaire. Qual Life Res. 2019 Jul;28(7):1963–77. doi: https://doi.org/10.1007/s11136-019-02161-5 DOI: https://doi.org/10.1007/s11136-019-02161-5
  45. Matthes KL, Zuberbuehler CA, Rohrmann S, Hartmann C, Siegrist M, Burnier M, et al. Selling, buying and eating – a synthesis study on dietary patterns across language regions in Switzerland. Br Food J. 2022;124(5):1502–18. doi: https://doi.org/10.1108/BFJ-02-2021-0141 DOI: https://doi.org/10.1108/BFJ-02-2021-0141
  46. Berger TM, Steurer MA, Bucher HU, Fauchère JC, Adams M, Pfister RE, et al.; Swiss Neonatal End-of-Life Study Group. Retrospective cohort study of all deaths among infants born between 22 and 27 completed weeks of gestation in Switzerland over a 3-year period. BMJ Open. 2017 Jun;7(6):e015179. doi: https://doi.org/10.1136/bmjopen-2016-015179 DOI: https://doi.org/10.1136/bmjopen-2016-015179
  47. Rey AM, Seidenberg A. Schwangerschaftsabbruch: die Praxis der Spitäler und Kliniken in der Schweiz. Schweiz Arzteztg. 2010;(91):551–4. DOI: https://doi.org/10.4414/saez.2010.15075
  48. Berger, F., et al., Overlapping borders: limit of viability and late terminations of pregnancy - a retrospective multicentre observational study. Swiss Med Wkly, 2020.150(0506):w20186. DOI: https://doi.org/10.4414/smw.2020.20186
  49. Wood AM, Pasupathy D, Pell JP, Fleming M, Smith GC. Trends in socioeconomic inequalities in risk of sudden infant death syndrome, other causes of infant mortality, and stillbirth in Scotland: population based study. BMJ. 2012 Mar;344 mar16 2:e1552. doi: https://doi.org/10.1136/bmj.e1552 DOI: https://doi.org/10.1136/bmj.e1552
  50. Panczak R, Berlin C, Voorpostel M, Zwahlen M, Egger M. The Swiss neighbourhood index of socioeconomic position: update and re-validation. Swiss Med Wkly. 2023 Jan;153(1):40028. doi: https://doi.org/10.57187/smw.2023.40028 DOI: https://doi.org/10.57187/smw.2023.40028

Most read articles by the same author(s)

1 2 3 > >>