[show abstract][hide abstract] ABSTRACT: Left atrial enlargement, a sensitive integrator of left ventricular diastolic function, is associated with increased cardiovascular morbidity and mortality. Vitamin D is linked to lower cardiovascular morbidity, possibly modifying cardiac structure and function; however, firm evidence is lacking. We assessed the effect of an activated vitamin D analog on left atrial volume index (LAVi) in a post hoc analysis of the PRIMO trial (clinicaltrials.gov: NCT00497146).
One hundred ninety-six patients with chronic kidney disease (estimated glomerular filtration rate 15-60 mL/min per 1.73m(2)), mild to moderate left ventricular hypertrophy, and preserved ejection fraction were randomly assigned to 2 μg of oral paricalcitol or matching placebo for 48 weeks. Two-dimensional echocardiography was obtained at baseline and at 24 and 48 weeks after initiation of therapy. Over the study period, there was a significant decrease in LAVi (-2.79 mL/m(2), 95% CI -4.00 to -1.59 mL/m(2)) in the paricalcitol group compared with the placebo group (-0.70 mL/m(2) [95% CI -1.93 to 0.53 mL/m(2)], P = .002). Paricalcitol also attenuated the rise in levels of brain natriuretic peptide (10.8% in paricalcitol vs 21.3% in placebo, P = .02). For the entire population, the change in brain natriuretic peptide correlated with change in LAVi (r = 0.17, P = .03).
Forty-eight weeks of therapy with an active vitamin D analog reduces LAVi and attenuates the rise of BNP. In a population where only few therapies alter cardiovascular related morbidity and mortality, these post hoc results warrant further confirmation.
American heart journal 12/2012; 164(6):902-909.e2. · 4.65 Impact Factor
[show abstract][hide abstract] ABSTRACT: Vitamin D is associated with decreased cardiovascular-related morbidity and mortality, possibly by modifying cardiac structure and function, yet firm evidence for either remains lacking.
To determine the effects of an active vitamin D compound, paricalcitol, on left ventricular mass over 48 weeks in patients with an estimated glomerular filtration rate of 15 to 60 mL/min/1.73 m(2).
Multinational, double-blind, randomized placebo-controlled trial among 227 patients with chronic kidney disease, mild to moderate left ventricular hypertrophy, and preserved left ventricular ejection fraction, conducted in 11 countries from July 2008 through September 2010.
Participants were randomly assigned to receive oral paricalcitol, 2 μg/d (n =115), or matching placebo (n = 112).
Change in left ventricular mass index over 48 weeks by cardiovascular magnetic resonance imaging. Secondary end points included echocardiographic changes in left ventricular diastolic function.
Treatment with paricalcitol reduced parathyroid hormone levels within 4 weeks and maintained levels within the normal range throughout the study duration. At 48 weeks, the change in left ventricular mass index did not differ between treatment groups (paricalcitol group, 0.34 g/m(2.7) [95% CI, -0.14 to 0.83 g/m(2.7)] vs placebo group, -0.07 g/m(2.7) [95% CI, -0.55 to 0.42 g/m(2.7)]). Doppler measures of diastolic function including peak early diastolic lateral mitral annular tissue velocity (paricalcitol group, -0.01 cm/s [95% CI, -0.63 to 0.60 cm/s] vs placebo group, -0.30 cm/s [95% CI, -0.93 to 0.34 cm/s]) also did not differ. Episodes of hypercalcemia were more frequent in the paricalcitol group compared with the placebo group.
Forty-eight week therapy with paricalcitol did not alter left ventricular mass index or improve certain measures of diastolic dysfunction in patients with chronic kidney disease.
clinicaltrials.gov Identifier: NCT00497146.
JAMA The Journal of the American Medical Association 02/2012; 307(7):674-84. · 29.98 Impact Factor
[show abstract][hide abstract] ABSTRACT: Chronic kidney disease is associated with a marked increase in risk for left ventricular hypertrophy and cardiovascular mortality compared with the general population. Therapy with vitamin D receptor activators has been linked with reduced mortality in chronic kidney disease and an improvement in left ventricular hypertrophy in animal studies.
PRIMO (Paricalcitol capsules benefits in Renal failure Induced cardia MOrbidity) is a multinational, multicenter randomized controlled trial to assess the effects of paricalcitol (a selective vitamin D receptor activator) on mild to moderate left ventricular hypertrophy in patients with chronic kidney disease.
Subjects with mild-moderate chronic kidney disease are randomized to paricalcitol or placebo after confirming left ventricular hypertrophy using a cardiac echocardiogram. Cardiac magnetic resonance imaging is then used to assess left ventricular mass index at baseline, 24 and 48 weeks, which is the primary efficacy endpoint of the study. Because of limited prior data to estimate sample size, a maximum information group sequential design with sample size re-estimation is implemented to allow sample size adjustment based on the nuisance parameter estimated using the interim data. An interim efficacy analysis is planned at a pre-specified time point conditioned on the status of enrollment. The decision to increase sample size depends on the observed treatment effect. A repeated measures analysis model, using available data at Week 24 and 48 with a backup model of an ANCOVA analyzing change from baseline to the final nonmissing observation, are pre-specified to evaluate the treatment effect. Gamma-family of spending function is employed to control family-wise Type I error rate as stopping for success is planned in the interim efficacy analysis.
If enrollment is slower than anticipated, the smaller sample size used in the interim efficacy analysis and the greater percent of missing week 48 data might decrease the parameter estimation accuracy, either for the nuisance parameter or for the treatment effect, which might in turn affect the interim decision-making.
The application of combining a group sequential design with a sample-size re-estimation in clinical trial design has the potential to improve efficiency and to increase the probability of trial success while ensuring integrity of the study.
[show abstract][hide abstract] ABSTRACT: In chronic kidney disease (CKD), left ventricular hypertrophy (LVH) is prevalent and is associated with increased cardiovascular morbidity and mortality. Vitamin D receptor (VDR) activation attenuates LVH progression in animal models.
PRIMO is a multinational, randomized, double-blinded trial with oral paricalcitol in subjects with stages 3-4 CKD, mild-to-moderate LVH and an LV ejection fraction >50%. The primary endpoint is change in the left ventricular mass index (LVMI) compared with placebo after 48 weeks of treatment. The main secondary endpoints are changes in diastolic function parameters. In this paper, we report baseline characteristics from this study.
LVMI was 33.0 ± 7.5 g/m(2.7) for males and 30.8 ± 7.2 g/m(2.7) for females (p = 0.04). LVMI correlated with systolic blood pressure (r = 0.24), urine albumin creatinine ratio (r = 0.39), troponin T (r = 0.29), high-sensitivity C-reactive protein (r = 0.25) and plasma levels of B-type brain natriuretic peptide (r = 0.22); all p < 0.01. In multiple linear regression, each remained independently associated with LVMI. The early diastolic velocity of the lateral mitral annulus (E') was 8.1 ± 2.4 cm/s. E' was inversely correlated with age in univariate (r = -0.14, p = 0.04) and multivariable (p = 0.02) analysis.
Among 227 multinational subjects with stages 3-4 CKD, baseline LVMI correlates with baseline blood pressure, urine albumin creatinine ratio and cardiac biomarkers, and baseline diastolic function correlates with age. This research was funded by Abbott Laboratories; ClinicalTrials.gov No. NCT00497146.
American Journal of Nephrology 01/2011; 33(2):139-49. · 2.62 Impact Factor