Large incidence variation of Type I diabetes in central-southern Italy 1990-1995: lower risk in rural areas.
OBJECTIVE
To evaluate the relation between the incidence of childhood Type I (insulin-dependent) diabetes mellitus and the degree of urbanization in the central-southern part of Italy.


METHODS
The incidence was determined in two areas: area A encompasses 3 regions of central-eastern Italy (Marche, Abruzzo, Umbria), whereas area B encompasses one southern region (Campania). During 1990-1995, 706 children aged 14 or under with insulin-dependent diabetes mellitus of recent onset were registered. The completeness of the case ascertainment in the registries analysed separately for each region was high, ranging from 96.3 % to 99%.


RESULTS
The age-standardized incidence was higher in area A (9.6 per 100000 person per year; 95 % confidence interval: 8.5-10.8) than in area B (5.4 per 100000 person per year; 95% confidence interval: 4.9-6.0). In both areas the standardized incidence ratios increased with the degree of urbanization (chi-squared for trend: area A= 140, p < 0.0001; area B = 79, p < 0.0001). The highest standardized incidence ratios were in the most urban communities.


CONCLUSIONS
This study showed a statistically significant difference in incidence of childhood insulin-dependent diabetes mellitus among different areas of the continental peninsula of Italy. People living in the rural communities appear to have a lower risk.
Cherubini
V
V
Institute of Paediatrics, University of Ancona, Italy.
Carle
F
F
Gesuita
R
R
Iannilli
A
A
Tuomilehto
J
J
Prisco
F
F
Iafusco
D
D
Altobelli
E
E
Chiarelli
F
F
De Giorgi
G
G
Falorni
A
A
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000453:epidemiology*; D005260:Female; D018740:Genetic Heterogeneity; D006801:Humans; D015994:Incidence; D007558:Italy / Q000453:epidemiology; D008297:Male; D012307:Risk Factors; D012423:Rural Health; D012959:Socioeconomic Factors; D014504:Urban Health