Incidence of diabetes mellitus among children of Italian migrants substantiates the role of genetic factors in the pathogenesis of type 1 diabetes.
To investigate the role of genetic and environmental factors in the pathogenesis of type 1 diabetes mellitus (T1D), we carried out a study in Germany aimed at comparing the prevalence and incidence of T1D among children of migrant Italians from high-risk (Sardinia) and low-risk (continental Italy) regions versus German children. Children from Italy were identified by the "Baden-Wuerttemberg (BW) Diabetes Incidence Registry", which registered 4017 newly diagnosed T1D patients, aged 0-14 years, between 1987 and 2003. Data relating to T1D children from Sardinia were elicited from more than 2000 questionnaires. Our findings were: (1) T1D is more frequent among German children than among children of Italian migrants [incidence rate (IR) 14.8/100,000/year, 95% confidence interval (CI) 14.4-15.4 vs. IR 10.8/100,000/year, 95% CI 8.2-13.6); (2) the incidence of T1D among Italian children residing in Germany is similar to that of Italian children in the home country (IR 10.8/100,000/year, 95% CI 8.2-13.6 vs. 8.4/100,000/year, 95% CI 7.9-8.9); (3) the prevalence of T1D among Sardinian children is higher than that among German children (0.11%, 95% CI 0.11-0.12) independent of the place where the Sardinian children are living (Sardinian children in Germany 2.3%, 95% CI 0.5-6.5 vs. Sardinian children in Sardinia 0.30%, 95% CI 0.27-0.32).


CONCLUSIONS
Children from high- and low-risk areas of Italy have incidence rates of T1D that are closer to those of their native regions than to those of German children, indicating that genetic factors play a predominant role in the pathogenesis of T1D.
Ehehalt
Stefan
S
University Hospital for Children and Adolescents, Hoppe-Seyler-Strasse 1, 72076 Tuebingen, Germany.
Popovic
Pavle
P
Muntoni
Sergio
S
Muntoni
Sandro
S
Willasch
Andre
A
Hub
Regine
R
Ranke
Michael B
MB
Neu
Andreas
A
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000208:ethnology / Q000235:genetics* / Q000503:physiopathology*; D054242:Emigrants and Immigrants / Q000706:statistics & numerical data*; D005838:Genotype; D005858:Germany / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D007558:Italy / Q000208:ethnology; D055815:Young Adult
Diabetes Metab Res Rev. 1999 Mar-Apr;15(2):133-40
10362460
Diabetes Care. 2002 May;25(5):840-6
11978678
Diabetes Care. 1997 Jun;20(6):983-7
9167110
Diabetes Care. 2004 Jul;27(7):1623-9
15220238
Diabetologia. 2002 Jun;45(6):783-91
12107721
Diabetologia. 2001 Oct;44 Suppl 3:B21-6
11724411
Diabetologia. 1992 Nov;35(11):1060-7
1473616
Ann Nutr Metab. 2006;50(1):11-9
16276070
Lancet. 1997 Jan 18;349(9046):160-2
9111539
Am J Clin Nutr. 2000 Jun;71(6):1525-9
10837294
Lancet. 1992 Apr 11;339(8798):905-9
1348306
BMJ. 1995 Oct 7;311(7010):913-7
7580548
Diabetes Care. 1993 Feb;16(2):528-34
8432228
Diabetes Care. 2001 Apr;24(4):785-6
11315850
BMJ. 1992 Apr 18;304(6833):1020-2
1586783
Int J Epidemiol. 2000 Jun;29(3):532-5
10869327
Diabetes Care. 2004 Dec;27(12):2790-6
15562186
Diabetes Care. 2000 Oct;23(10):1516-26
11023146
Diabet Med. 2006 Aug;23(8):857-66
16911623
Diabetes Care. 2001 Apr;24(4):650-3
11315825
Lancet. 1992 Feb 22;339(8791):494-5
1346847