Perinatal risk factors for diabetes in later life.
OBJECTIVE
Low birth weight is consistently associated with an increased risk of type 2 diabetes in adulthood, but the individual contributions from poor fetal growth and preterm birth are not known. We therefore investigated the significance of these two factors separately.


METHODS
We identified a cohort of subjects born preterm or with low birth weight at term at four major delivery units in Sweden from 1925 through 1949. A comparison cohort of subjects was identified from the same source population. Of 6,425 subjects in all, 2,931 were born at <37 weeks of gestation and 2,176 had a birth weight <2,500 g. Disease occurrence among participants was assessed through nationwide hospital registers from 1987 through 2006.


RESULTS
During follow-up, there were 508 cases of diabetes. Low birth weight was strongly negatively associated with risk of diabetes (P for trend <0.0001). Both short gestational duration and poor fetal growth were associated with later diabetes (P for trend <0.0001 and <0.0004, respectively). Very preterm birth (< or =32 weeks of gestation at birth) was associated with a hazard ratio (HR) of 1.67 (95% CI 1.33-2.11) compared with term birth. Birth weights below 2 SDs of mean birth weight for gestational age were associated with an HR of 1.76 (1.30-2.38) compared with birth weights between the mean weight and the weight at 1 SD above the mean.


CONCLUSIONS
Our results suggest that the association between low birth weight and diabetes is due to factors associated with both poor fetal growth and short gestational age.
Kaijser
Magnus
M
Clinical Epidemiology Unit, Department of Medicine, Karolinska Institutet, Stockholm, Sweden. magnus.kaijser@ki.se
Bonamy
Anna-Karin Edstedt
AK
Akre
Olof
O
Cnattingius
Sven
S
Granath
Fredrik
F
Norman
Mikael
M
Ekbom
Anders
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001724:Birth Weight; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology*; D005260:Female; D047109:Fetal Development / Q000502:physiology; D005865:Gestational Age; D006339:Heart Rate; D006801:Humans; D007230:Infant, Low Birth Weight / Q000254:growth & development*; D007231:Infant, Newborn; D007234:Infant, Premature / Q000254:growth & development*; D019102:Infant, Very Low Birth Weight / Q000254:growth & development*; D008297:Male; D008875:Middle Aged; D012042:Registries; D012307:Risk Factors; D012959:Socioeconomic Factors; D013548:Sweden / Q000453:epidemiology