Evidence from a study published in the January issue of Journal of Clinical Lipidology, Volume 7, Issue 1, Pages 14 – 23 reports inositol hexanicotinate (IHN) ineffective in managing high cholesterol. The study, which published clinical results comparing an extended-release form of niacin to IHN and a placebo, simultaneously confirms a wax-matrix form of extended release niacin can help lower cholesterol.
Conducted by Joseph M. Keenan, MD, and a team of researchers from the University of Minnesota, the study examined 120 subjects with high cholesterol at the University’s Clinical Research Center. Subjects received instruction for a heart-healthy diet, and were monitored for diet, medication side effects, blood chemistries, blood lipids and dosing compliance throughout the study. Five subjects from each group were randomly selected for a pharmaco-kinetic sub-study in the research center. Blood tests over eight hours were used to measure the absorption rate and metabolism of the subjects’ first 500 mg dose of wax-matrix, extended release niacin.
Results showed IHN and placebo produced no significant improvement in blood lipids. Conversely, wax-matrix niacin, demonstrated positive lipid benefits, reducing total cholesterol 11 percent, LDL cholesterol 18 percent, non-HDL cholesterol 15 percent and triglycerides nine percent. It also promoted an increase in HDL cholesterol by 12 percent.
“IHN has been a popular choice for niacin therapy, especially by alternative health providers because of its ‘no flush’ claim. However, there has never been a controlled study of IHN conducted on a United States population, and several European studies using IHN were combination interventions making it difficult to measure the contribution of IHN to lipid benefits,” said principal investigator Joseph Keenan, MD. “This clinical trial was a six-week placebo controlled comparison of 1500 mg/day of the two niacin products, which also included a pharmaco-kinetic sub-study designed to give health professionals a scientific basis for making their choice in niacin therapy.”
Previous studies with wax-matrix niacin have shown that about 15 percent of subjects are especially sensitive to niacin, and instead utilize a lower than typical therapeutic dose. Six subjects in the wax-matrix niacin arm of this study completed the study on a reduced dose (500 to 1000 mg/day) and had comparable lipid benefits to the full dose subjects. Blood chemistry monitoring showed a modest rise in liver enzymes within the range of normal, which was not considered clinically significant.