Diabetes Care, Vol 18, Issue 12 1600-1601, Copyright © 1995 by American Diabetes Association
Steadily high IDDM incidence over 4 years in Sardinia
S Muntoni, L Stabilini, M Stabilini, G Mancosu and S Muntoni
Center for Metabolic Diseases and Atherosclerosis, Cagliari, Italy.
OBJECTIVE: To verify whether the high incidence of insulin-dependent
diabetes mellitus (IDDM) in Sardinia is an epidemic outbreak or a steady
phenomenon. RESEARCH DESIGN AND METHODS: All newly diagnosed cases of IDDM
with onset in patients 0-29 years of age between 1 January 1989 and 31
December 1992 among residents in Sardinia were obtained from the Sardinian
IDDM Incidence Registry. The local IDDM patient association (Associazione
Diabete Infantile Giovanile) served as the secondary and independent
source. RESULTS: The completeness of ascertainment was 91%. The
age-standardized mean annual incidence of IDDM (per 100,000) was 34.4 in
the 0- to 14-year-old age-group and 26.2 in the entire 0- to 29-year-old
range, respectively. Men-to-women ratios were 1.38 and 1.55, respectively.
Seasonal variation in incidence was observed, with a peak in fall and
winter and a nadir in summer. CONCLUSIONS: Sardinia has a very high and
steady IDDM incidence rate, which is up to fivefold that of other Italian
regions and Mediterranean countries and approaches the Finnish top rate in
the world. Interaction between the genetic peculiarity of Sardinians and
still unidentified powerful environmental agents is likely to account for
the phenomenon.