Identification and Clinical Characterization of Adult Patients with Multigenerational Diabetes Mellitus.
BACKGROUND
Some patients diagnosed as having type 2 diabetes mellitus (T2DM) are, instead, affected by multigenerational diabetes whose clinical characteristics are mostly undefined.


OBJECTIVE
1. To identify among patients who had been previously defined as affected by T2DM those, in fact, affected by multigenerational diabetes; 2. After excluding patients carrying the most common MODY genes and mitochondrial mutations, we compared clinical features of remaining patients with those of patients with T2DM.


METHODS
Among 2,583 consecutive adult patients who had been defined as affected by T2DM, we looked for those with diabetes in ≥3 consecutive generations. All probands were screened for mutations in six MODY genes (HNF4A, GCK, HNF1A, PDX1, HNF1B and NeuroD1) and for the A3243G mitochondrial mutation. After excluding patients with mutations in one of such genes, we compared clinical features of the remaining 67 patients (2.6% of the whole initial sample) affected by multigenerational "familial diabetes of the adulthood" (FDA) and of their diabetic relatives (n = 63) to those with T2DM (n = 1,028) by generalized hierarchical linear models followed by pairwise comparisons.


RESULTS
Age, age at diagnosis, proportion of hypertension (all p<0.001), and waist circumference (p<0.05) were lower in FDA than T2DM. Nonetheless, the two groups had similar age-adjusted incidence rate of all-cause mortality.


CONCLUSIONS
Beside younger age at diagnosis, FDA patients show lower waist circumference and reduced proportion of hypertension as compared to those with T2DM; despite such reduced potential cardiovascular risk factors, FDA patients did not show a reduced mortality risk than patients with T2DM.
Endocrine Clinical Unit, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy.
Ornella
O
Ludovico
Medical Genetics Unit, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy.
Massimo
M
Carella
Medical Genetics Unit, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy.
Luigi
L
Bisceglia
Mendel Laboratory, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy; Department of Experimental Medicine, "Sapienza" University of Rome, Rome, Italy.
Giorgio
G
Basile
Unit of Cardiology, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy.
Sandra
S
Mastroianno
Endocrine Clinical Unit, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy.
Antonio
A
Palena
Unit of Medicine, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy.
Salvatore
S
De Cosmo
Unit of Biostatistics, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy.
Massimiliano
M
Copetti
Mendel Laboratory, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy.
Sabrina
S
Prudente
Mendel Laboratory, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy; Department of Experimental Medicine, "Sapienza" University of Rome, Rome, Italy; Research Unit of Diabetes and Endocrine Diseases, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy.
Vincenzo
V
Trischitta
D000328:Adult; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics* / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008928:Mitochondria / Q000235:genetics; D009154:Mutation / Q000235:genetics; D012307:Risk Factors