A randomized pilot study on the effect of niacin on pulmonary arterial pressure.
- 2015
Available online through MWHC library: 2006 - present
BACKGROUND: Niacin induces the release of vasodilating prostaglandins, for which receptors are present within the pulmonary arterial circulation. We hypothesized that immediate-release niacin would reduce right ventricular systolic pressure in patients with pulmonary hypertension in a randomized, double-blinded, single-dose provocation study. CONCLUSIONS: A single dose of immediate-release niacin (100 mg or 500 mg) had no significant effect on RVSP 1 hour post administration. A nonsignificant dose-dependent trend for a modest reduction in RVSP, most notable in the 500 mg group, was noted. (ISRCTN number 12353191, registered April 23, 2015). METHODS: We recruited inpatient subjects with a Doppler echocardiogram showing a peak tricuspid regurgitation (TR) jet velocity of 2.7 m/s or greater, and who were free of known pulmonary vascular disease. Subjects were randomized in a 1:2:2 ratio to receive a single dose of either placebo, niacin 100 mg or niacin 500 mg, respectively. TR jet velocities were measured immediately before, and 1 hour post dose, corresponding to peak niacin absorption and prostaglandin release. The primary endpoint was the change in mean TR jet velocity measured over ten successive cardiac cycles. RESULTS: The baseline mean estimated right ventricular systolic pressure (RVSP) for all 49 subjects (25 male) was 51.9+/-12.1 mm Hg. The primary endpoint of mean change in TR jet velocity was 0.016+/-0.065 m/s in the placebo group, compared to -0.017+/-0.065 m/s with niacin 100 mg, and -0.063+/-0.038 m/s with niacin 500 mg (P=0.63). The change in maximum estimated RVSP across the three drug groups was 0.2+/-1.6 mm Hg, -1.3+/-1.8 mm Hg and -2.2+/-1.2 mm Hg (P=0.62). In exploratory pairwise analysis in the high-dose niacin group (500 mg), the reduction in mean RVSP was from 50.9+/-9.4 mm Hg to 48.7+/-10.0 mm Hg (P=0.09).
English
1745-6215
*Antihypertensive Agents/tu [Therapeutic Use] *Arterial Pressure/de [Drug Effects] *Hypertension, Pulmonary/dt [Drug Therapy] *Niacin/tu [Therapeutic Use] *Pulmonary Artery/de [Drug Effects] *Vasodilator Agents/tu [Therapeutic Use] Aged Aged, 80 and over Antihypertensive Agents/ae [Adverse Effects] District of Columbia Double-Blind Method Echocardiography, Doppler Female Humans Hypertension, Pulmonary/pp [Physiopathology] Hypertension, Pulmonary/us [Ultrasonography] Male Middle Aged Niacin/ae [Adverse Effects] Pilot Projects Pulmonary Artery/pp [Physiopathology] Pulmonary Artery/us [Ultrasonography] Time Factors Treatment Outcome Vasodilator Agents/ae [Adverse Effects] Ventricular Function, Right/de [Drug Effects] Ventricular Pressure/de [Drug Effects]
MedStar Heart & Vascular Institute
Journal Article Randomized Controlled Trial Research Support, Non-U.S. Gov't