Vol 11, No 5 (2010): Practical Diabetology
Other materials agreed with the Editors
Published online: 2011-02-16
Maternal age at birth and childhood type 1 diabetes: a pooled analysis of 30 observational studies
Diabetologia Praktyczna 2010;11(5):181-193.
Abstract
OBJECTIVE. The aim if the study was to investigate
whether children born to older mothers have an increased
risk of type 1 diabetes by performing a pooled
analysis of previous studies using individual
patient data to adjust for recognized confounders.
MATERIAL AND METHODS. Relevant studies published before June 2009 were identified from MEDLINE, Web of Science, and EMBASE. Authors of studies were contacted and asked to provide individual patient data or conduct prespecified analyses. Risk estimates of type 1 diabetes by maternal age were calculated for each study, before and after adjustment for potential confounders. Meta-analysis techniques were used to derive combined odds ratios and to investigate heterogeneity among studies.
RESULTS. Data were available for 5 cohort and 25 casecontrol studies, including 14,724 cases of type 1 diabetes. Overall, there was, on average, a 5% (95% CI 2–9) increase in childhood type 1 diabetes odds per 5-year increase in maternal age (P = 0.006), but there was heterogeneity among studies (heterogeneity I2 = 70%). In studies with a low risk of bias, there was a more marked increase in diabetes odds of 10% per 5-year increase in maternal age. Adjustments for potential confounders little altered these estimates.
CONCLUSIONS. There was evidence of a weak but significant linear increase in the risk of childhood type 1 diabetes across the range of maternal ages, but the magnitude of association varied between studies. A very small percentage of the increase in the incidence of childhood type 1 diabetes in recent years could be explained by increases in maternal age. (Diabet. Prakt. 2010; 11, 5: 181–193)
MATERIAL AND METHODS. Relevant studies published before June 2009 were identified from MEDLINE, Web of Science, and EMBASE. Authors of studies were contacted and asked to provide individual patient data or conduct prespecified analyses. Risk estimates of type 1 diabetes by maternal age were calculated for each study, before and after adjustment for potential confounders. Meta-analysis techniques were used to derive combined odds ratios and to investigate heterogeneity among studies.
RESULTS. Data were available for 5 cohort and 25 casecontrol studies, including 14,724 cases of type 1 diabetes. Overall, there was, on average, a 5% (95% CI 2–9) increase in childhood type 1 diabetes odds per 5-year increase in maternal age (P = 0.006), but there was heterogeneity among studies (heterogeneity I2 = 70%). In studies with a low risk of bias, there was a more marked increase in diabetes odds of 10% per 5-year increase in maternal age. Adjustments for potential confounders little altered these estimates.
CONCLUSIONS. There was evidence of a weak but significant linear increase in the risk of childhood type 1 diabetes across the range of maternal ages, but the magnitude of association varied between studies. A very small percentage of the increase in the incidence of childhood type 1 diabetes in recent years could be explained by increases in maternal age. (Diabet. Prakt. 2010; 11, 5: 181–193)