Insulin resistance, hypertension and nephropathy

Area of Science:

• Endocrinology
• Nephrology
• Cardiovascular Medicine

Background:

• Insulin resistance is implicated in essential hypertension in non-diabetic individuals.
• Limited research exists on the link between insulin resistance, hypertension, and nephropathy in diabetes mellitus.

Purpose of the Study:

• To investigate the association between insulin resistance, hypertension development, and nephropathy progression over 7 years in non-obese, normotensive patients with non-insulin-dependent diabetes mellitus (NIDDM).

Main Methods:

• Prospective observation of 28 NIDDM patients (age >40, fasting glucose <140 mg/dl) over 7 years.
• Insulin sensitivity assessed via glucose-clamp or glucose, insulin, and somatostatin infusion.
• Monitoring of blood pressure and proteinuria.

Main Results:

• 12 of 28 patients developed hypertension; 16 remained normotensive.
• Insulin-induced glucose clearance was significantly lower in hypertensive subjects (30 ± 12 ml/kg/10 min) compared to normotensive subjects (50 ± 19 ml/kg/10 min).
• Proteinuria incidence was significantly higher in hypertensive patients (7/12) than normotensive patients (1/16; p < 0.05).

Conclusions:

• Insulin resistance is a key factor in the etiology of hypertension among NIDDM patients.
• Insulin resistance plays a significant role in the progression of diabetic nephropathy.