Correct Option
Diabetes mellitus is a chronic metabolic disorder characterized by persistently high blood glucose levels (hyperglycemia). This condition arises either from the pancreas's inability to produce sufficient insulin (absolute deficiency) or the body's cells becoming resistant to the effects of insulin (relative deficiency), or both.
- Higher sugar level in blood (Statement 1): This is the defining characteristic of diabetes mellitus, as the body cannot effectively regulate glucose.
- Lower insulin level in blood (Statement 3): In Type 1 diabetes, there is an absolute deficiency of insulin due to autoimmune destruction of pancreatic beta cells. In Type 2 diabetes, while initial stages might involve compensatory higher insulin levels due to resistance, over time, the pancreatic beta cells often fail, leading to insufficient insulin production and thus lower circulating insulin levels. Therefore, a functional or absolute deficiency of insulin is a key association.
Incorrect Options
- Lower sugar level in blood (Statement 2): Hypoglycemia (low blood sugar) is not a characteristic feature of untreated diabetes mellitus. The disease is defined by hyperglycemia.
- Higher insulin level in blood (Statement 4): While higher insulin levels (hyperinsulinemia) can be observed in the early stages of Type 2 diabetes as the body attempts to overcome insulin resistance, this is often a precursor to eventual beta-cell failure and lower insulin production. More fundamentally, the issue is the ineffectiveness of insulin, and the long-term trend or the state of insulin deficiency (functional or absolute) is more broadly associated with the disease's progression and management. Given that option 3 (lower insulin level) is part of the correct answer, it points to the more critical and often eventual state of insulin insufficiency.
- Options combining "Lower sugar level" (2 and 4, 1 and 2, 2 and 3) are incorrect because diabetes mellitus is fundamentally a condition of elevated blood glucose.