Table 1.

Contrasting clinical and pathophysiologic features of types 1 and 2 diabetes

Features	Type 1 DM	Type 2 DM
Age at onset	Early, below 35 yr	Late, after 40-45 yr
Type of onset	Abrupt and severe	Gradual and insidious
Frequency of occurrence	10%-20%	80%-90%
Family history	Less than 20%	About 60%
Pathogenesis	Autoimmune destruction of β-cells	Insulin resistance, impaired insulin secretion
Body weight	Normal	Obese/non-obese
Genetic locus	Unknown	Chromosome 6
Condition of islet cells	Insulitis, β-cell destruction	No insulitis, later fibrosis of islets
Blood insulin level	Decreased insulin	Normal or increased insulin
Clinical management	Insulin and diet	Insulin, oral drugs, diet, exercise

DM: Diabetes mellitus.