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The large worldwide variation in type 1 diabetes incidence and increasing incidence over time points toward important environmental risk factors. Among them, nutrition plays an important role. The objective was to investigate the relationship between type 1 diabetes and nutritional factors in pregnancy and early in life. We carried out, using semi-quantitative food frequency questionnaires, a retrospective case-control study in 298 children of 0-15 years old, 145 of which were affected by type 1 diabetes. The diet of all children and of their mothers during pregnancy and lactation was assessed. In children, a statistically significant dose-response association between type 1 diabetes and the amount of meat consumption was found while no other nutritional factors were associated with the disease. High meat consumption seems to be an important early in life cofactor for type 1 diabetes development, although these findings need to be confirmed in wider prospective follow-up studies.

We aimed at updating the prevalence of impaired fasting glucose (IFG) and of undiagnosed (UD) and diagnosed diabetes (DD) among the Sardinian population. The survey was carried out from 2002 to 2005 on 4.737 subjects aged 20-80+ years. IFG was diagnosed when blood glucose was 110-125 mg/dl; UD when it was >or=126 mg/dl in the absence of personal history of diabetes; DD when personal history was positive, irrespective of blood glucose value. Prevalence rates (%) were adjusted for age by direct method to the Italian 2001 population. IFG was diagnosed in 11% of the sample (9.88% in females and 12.24% in males); UD was found in 5.65% (5.20 and 6.15%, females and males, respectively), DD in 8.72% (6.74 and 10.05%); and total diabetes (TD), i.e. the sum of UD + DD, was 14.37% (12.93 and 15.07%, females and males, respectively). In Sardinia, in about 5 years there was an increase of IFG (+61.8%), UD (+56.9%), DD (+55.7%), and TD (+57.9%). Thus Sardinia participates in the worldwide increase in prevalence of diabetes and its microvascular, macrovascular, and socioeconomic consequences.

Unlabelled: 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)., Conclusion: 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.

A frequent missense mutation (Thr-6Pro) found in the prepeptide of the lysosomal acid lipase (LAL) gene was analyzed in a cohort of 1003 randomly selected samples from Germany, Japan and Sardinia (Italy). Using the mutagenically separated polymerase chain reaction (MS-PCR), allele frequencies of 0.269, 0.238 and 0.245 were determined in the three populations, respectively. Statistical analysis showed a lack of association with a dyslipidemic phenotype in all three groups. Additionally, in a subgroup of 126 German individuals no association was observed between genotype and LAL activity. We conclude that this mutation appears to be a frequent LAL gene polymorphism causing no impaired function of the enzyme and no measurable dyslipidemia in the general population.

Deficiency of lysosomal acid lipase is expressed in two distinct recognizable phenotypes. Wolman disease represents the severe early onset form, whereas cholesterol ester storage disease is the more benign late onset type. Previous studies have indicated that compound heterozygosity consisting of a G-->A mutation at the 3'-splice junction of exon 8 (E8SJM-allele) together with a null allele of the gene encoding lysosomal acid lipase leads to cholesterol ester storage disease. We have now observed homozygosity for the G-->A splice junction mutation in a non-related Spanish kindred with the same disease. As expected, the residual activity of lysosomal acid lipase is higher in this case, suggesting that the E8SJM-allele is associated with low residual acid lipase activity. However, the phenotype of the homozygous propositus is more severe compared with the previously described case, indicating that no direct relationship exists between the genotype or residual LAL activity and the precise cholesterol or triglyceride levels in a given patient. Nevertheless, our findings provide convincing evidence that homozygosity for the E8SJM-allele causes cholesterol ester storage disease to at least the same extent as compound heterozygosity consisting of this allele and a null allele.

In order to obtain new and more detailed information about temporal trends and geographic distribution of Type 1 (insulin-dependent) diabetes mellitus in Sardinia, we screened a series of birth cohorts (1936-1973) of all male army conscripts aged 18-19 years, filed in the Sardinian Conscript Register where Type 1 diabetes is a cause of rejection. A total of 678 diabetic subjects, born and permanently residing in Sardinia, was identified. The point prevalence (x 1000) at the age of 20 years in the birth cohorts ranged from values close to zero for the first ten cohorts (1936-1945) up to a maximum of 3.08 (95% confidence limits 2.28-4.08) for the 1966 cohort and continued high thereafter although an apparent decrease was observed from the early 1970s birth cohorts. Type 1 diabetes was distributed throughout the four provinces of Sardinia with no particularly significant heterogeneity; however, in accordance with the geographical distribution of diabetes cases of the Eurodiab Ace survey (1989-1990), the highest prevalence of the disease was observed in the Cagliari and Oristano provinces, followed by Nuoro and Sassari. These data suggest a gradually increasing trend of male Type 1 diabetes prevalence in Sardinia with a 29-fold increase between the late 1930s and the late 1960s birth cohorts. This seems to confirm the high incidence of Type 1 diabetes in the 0-14 and 0-29 year age groups recently reported among Sardinians during the Eurodiab Ace collaborative multicentre study.