The prevalence of systemic hypertension is increased in patients with diabetes. In this prospective, randomized, crossover clinical trial, we assessed antihypertensive effects of chronic intermittent intravenous insulin therapy (CIIIT) on insulin-dependent diabetes mellitus (IDDM) subjects with hypertension and nephropathy by monitoring the amount of antihypertensive medication (AHM) required to maintain blood pressure (BP) ≤ 140/90 mmHg.
After a stabilization period, 26 hypertensive IDDM subjects were randomly assigned to a control or treatment phase for 3 months and then crossed over into the opposite phase for another 3 months. Addition of CIIIT during the treatment phase was the only procedural difference between the control and treatment phases.
The AHM dosage requirements for maintenance of the baseline BP levels decreased significantly (46% P < 0.0001) and linearly over time (P < 0.0058) during the treatment phase, while remaining essentially unchanged during the control phase.
Our data suggest that CIIIT markedly improves BP control, as evidenced by the significantly reduced AHM dosage requirements in subjects with IDDM and hypertension, possibly through an improvement in vascular reactivity.