Effects of Niacin Therapy on Lipoprotein Composition and Function

Not Applicable

Completed

Brief Summary: Background:

- Niacin is a vitamin in many foods, including meats, fish, fruits, and vegetables. It is often used as a dietary supplement that causes many improvements in the body. Researchers think it can affect heart health.

Objective:

- To better understand the good effects of niacin supplementation on cholesterol, fat metabolism, and vascular health.

Eligibility:

- Adults 18 years of age and older with fasting good cholesterol (HDL-C) below 60 mg/dL.

Design:

* Participants will come to the clinic 4 times during the study.

* They will complete a 7-day food journal before visits 1 and 3.

* At visit 1, participants will be screened with questions about their diet and exercise, medical history, and any drugs and vitamins they take. Vital signs and body mass index will be measured.

* They will have a Cardio-Ankle Vascular Index (CAVI) test of the arteries. Blood pressure will be taken in the arms and legs and the heart will be monitored.

* Blood will be drawn. Participants will fast for 8 12 hours before this.

* Women will have a pregnancy test.

* Eligible participants will get a 2-week supply of niacin. They will take 2 tablets daily for one week, then 4 daily.

* Visit 2 will be 2 weeks after visit 1 and the niacin dose will be increased. Visit 3 will be 16 weeks after visit 1, and participants will stop taking niacin. Visit 4 will be 4 6 weeks after stopping niacin.

* During study visits, participants will repeat visit 1 tests.

Detailed Description: This single center clinical pilot study will investigate the effects of niacin on blood lipids and lipoprotein composition in human subjects who are healthy. Niacin (vitamin B3 or nicotinic acid) is a common nutrient found in many foods and is currently sold over the counter as a nutritional supplement. Extended-release versions of niacin are available over the counter (e.g., Slo-Niacin) or by prescription (Niaspan) and help to alleviate symptoms of flushing associated with larger doses of the vitamin. Studies of the effects of niacin therapy on clinical lipid measures consistently indicate a shift toward a healthier lipoprotein profile with increased HDL-C and decreases in both triglyceride and LDL-C. Despite this favorable shift in lipid profile, cardiovascular outcome studies on patients receiving niacin alone or in combination with statin therapy have resulted in mixed results creating uncertainty of the value of niacin therapy. The proposed study will examine in detail the effects of niacin therapy on lipoprotein composition and function, while also tracking measures of vascular health.

Recruitment & Eligibility

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Arm && Interventions

Group	Intervention	Description
Niacin ER in healthy participants and its effects on lipoprotein composition and function	Niacin Extended Release	Niacin extended release (ER) to be given as follows: 500 mg/day for 1 week, then 1000 mg/day for 1 week, then 2000 mg/day for 14 weeks in healthy participants.

Primary Outcome Measures

Name	Time	Method
Mean Percent Change in High-density Lipoprotein Protein Concentration	20 weeks	Measure the mean percentage of niacin monotherapy on high-density lipoprotein (HDL) protein concentration
Change in Proteins of High-density Lipoprotein Protein Composition on Niacin Monotherapy	20 weeks	Measure the effect proteins with changes in protein composition of niacin monotherapy on high-density lipoprotein (HDL) protein composition. High-density lipoprotein protein were measured using Nuclear magnetic resonance (NMR) spectroscopy. NMR spectroscopy is a technique that uses the magnetic properties of atomic nuclei to analyze the chemical and physical properties of molecules or atoms. NMR spectroscopy is non-destructive and non-invasive, and can be used to study the structure, dynamics, and chemical reactions of molecules. NMR procedures numerical results which are comparable to laboratory results, and these data were used to measure the outcomes reported.

Secondary Outcome Measures