H Scherb1, E Weigelt, I Brüske-Hohlfeld. 1. GSF-Forschungszentrum für Umwelt und Gesundheit, Institut für Biomathematik und Biometrie, Oberscheissheim, Germany. scherb@gsf.de
Abstract
BACKGROUND: Numerous investigations have been carried out concerning the possible impact of the Chernobyl accident, in April 1986, on the prevalence of anomalies at birth and on perinatal mortality. The accident has contaminated Eastern Europe more heavily than Western Europe. If there was an effect of the radioactive contamination on perinatal mortality or stillbirth proportions one would expect to find it more pronounced in Eastern Europe as compared to Western Europe. We therefore studied long-term time trends in European stillbirth proportions. METHODS: Linear logistic regression was applied to model the time trends in stillbirth proportions. Dummy variables were used to account for effects that can be associated with certain years or locations. A synoptic logistic regression model is suggested for the western, central, and eastern parts of Europe. RESULTS: There is a marked differential effect in the long-term stillbirth time trends between Western Europe (Belgium, France, Great Britain, Iceland, Ireland, Luxembourg, Portugal, Spain), Central Europe (Austria, Denmark, Germany, Italy, Norway, Switzerland), and Eastern Europe represented by four countries (Greece, Hungary, Poland, Sweden). In contrast to the western and central European trends, the eastern European trend exhibits an absolute increase of the stillbirth proportion in 1986 as compared with 1985 and an apparent upward shift of the whole trend line from 1986 on. CONCLUSION: Our results are in contrast to those of many analyses of the health consequences of the Chernobyl accident and contradict the present radiobiological knowledge. As we are dealing with highly aggregated data, other causes or artefacts may explain the observed effects. Hence, the findings should be interpreted with caution and further independent evidence should be sought.
BACKGROUND: Numerous investigations have been carried out concerning the possible impact of the Chernobyl accident, in April 1986, on the prevalence of anomalies at birth and on perinatal mortality. The accident has contaminated Eastern Europe more heavily than Western Europe. If there was an effect of the radioactive contamination on perinatal mortality or stillbirth proportions one would expect to find it more pronounced in Eastern Europe as compared to Western Europe. We therefore studied long-term time trends in European stillbirth proportions. METHODS: Linear logistic regression was applied to model the time trends in stillbirth proportions. Dummy variables were used to account for effects that can be associated with certain years or locations. A synoptic logistic regression model is suggested for the western, central, and eastern parts of Europe. RESULTS: There is a marked differential effect in the long-term stillbirth time trends between Western Europe (Belgium, France, Great Britain, Iceland, Ireland, Luxembourg, Portugal, Spain), Central Europe (Austria, Denmark, Germany, Italy, Norway, Switzerland), and Eastern Europe represented by four countries (Greece, Hungary, Poland, Sweden). In contrast to the western and central European trends, the eastern European trend exhibits an absolute increase of the stillbirth proportion in 1986 as compared with 1985 and an apparent upward shift of the whole trend line from 1986 on. CONCLUSION: Our results are in contrast to those of many analyses of the health consequences of the Chernobyl accident and contradict the present radiobiological knowledge. As we are dealing with highly aggregated data, other causes or artefacts may explain the observed effects. Hence, the findings should be interpreted with caution and further independent evidence should be sought.