Improvement of insulin sensitivity by a long-acting nifedipine preparation (nifedipine-CR) in patients with essential hypertension

Abstract

BACKGROUND: Nifedipine has been reported to cause impairment of insulin sensitivity. But recently a controlled-released formulation of nifedipine (nifedipine-GITS) has been reported that it could improve insulin sensitivity. METHODS: We evaluated insulin sensitivity in two groups of essential hypertensive subjects before and after treatment with either long-acting nifedipine (nifedipine-CR, Adalat CR tablets; Bayer Yakuhin, Osaka, Japan) (n = 10) or metoprolol (n = 9). Insulin sensitivity was evaluated from the steady-state plasma glucose (SSPG) level measured at the steady-state insulin level (20 to 30 microU/mL) using a modification of the SSPG method previously reported. RESULTS: The SSPG was initially high, but was significantly reduced by nifedipine-CR treatment (from 133 +/- 14 mg/dL to 95 +/- 8 mg/dL). However, SSPG was not significantly altered by treatment in the metoprolol group (from 103 +/- 15 mg/dL to 119 +/- 12 mg/dL). CONCLUSIONS: Our results indicate that the long-acting nifedipine (nifedipine-CR) is associated with improved insulin sensitivity.