Table 1. Clinical, biochemical, and pathogenetic features of T1DM, LADA, and T2DM.
| T1DM | LADA | T2DM | |
|---|---|---|---|
| Clinical features | |||
| Age at onset | Childhood/adolescence | 30–50 yr | Adulthood |
| Symptoms of hyperglycemia at onset | Frequently acute | Subclinical (rarely acute) | Silent/subclinical |
| Insulin requirement | At diagnosis | >6 mo after diagnosis | Absent or years after diagnosis |
| Insulin resistance | No change | Increased/no change | Increased |
| BMI | <25 kg/m2 (frequently <18 kg/m2) | >25 kg/m2 (rarely >25 kg/m2) | >25 kg/m2 |
| Risk of long-term complications at diagnosis | Low | Low | High |
| Biochemical features | |||
| Islet-cell autoantibodies | High titre (rarely low) | High/low titre | Absent |
| C-peptide levels at diagnosis | Non-detectable (rarely decreased) | Decreased but still detectable | Normal/ increased |
| Pathophysiology features | |||
| MHC association | High risk | High/mild risk | Mild risk |
| Family history of diabetes | Negative/positive | Negative/positive | Frequently positive |
| Family history of autoimmune disease | Frequently positive | Frequently positive | Negative (no correlation) |
T1DM, type 1 diabetes mellitus; LADA, latent autoimmune diabetes in adults; T2DM, type 2 diabetes mellitus; BMI, body max index; MHC, major histocompatibility complex.