The effect of prolonged treatment with
Acipimox on in vivo peripheral
insulin sensitivity, and on
glucose and lipid metabolism, was investigated in patients with
NIDDM in a double-blind study. Twelve
NIDDM patients were randomized to treatment with either placebo or
Acipimox in pharmacological doses (250 mg x 3) for three months. Fasting plasma
glucose,
insulin,
C-peptide and HbA1c concentrations were unaffected after three months of
acipimox treatment. However, fasting plasma non-
esterified fatty acid (
NEFA) concentrations were twofold elevated after
Acipimox treatment (1.34 +/- 0.09 vs 0.66 +/- 0.09 mmol/l; p < 0.05). Despite this, repeated acute
Acipimox administration after the three months' treatment period enhanced total
insulin-stimulated
glucose disposal to the same extent as acute
Acipimox administration before the treatment period (367 +/- 59 vs 392 +/- 66 mg.m-2.min-1, NS; both p < 0.05 vs placebo
glucose disposal) (267 +/- 44 mg.m-2.min-1). In conclusion,
insulin resistance or tachyphylaxis towards the effects of
Acipimox on
insulin stimulated
glucose disposal was not induced during prolonged
Acipimox treatment. The lack of improvement of
blood glucose control in the patients with
NIDDM may be due to the demonstrated rebound effect of lipolysis.