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Brian Schreiber

Publications and source records attributed to Brian Schreiber.

6 recordsLinked to original sources
PubMed2005

Carnitine therapy is associated with decreased hospital utilization among hemodialysis patients.

BACKGROUND/AIMS: Hospitalizations account for 41% of the total cost of end-stage renal disease (ESRD) care. Carnitine deficiency is common among dialysis patients, and some studies have shown improvements in anemia, and cardiac and skeletal muscle function upon administration of L-carnitine. We hypothesized that L-carnitine may be associated with decreased hospital utilization in these patients. METHODS: The Fresenius Medical Care North America dialysis database was used for this retrospective analysis. Adult patients who received carnitine for at least 3 months, and had at least 3 months of pre-carnitine follow-up were included in the study. Hospitalization and hospital day rates were compared before and during carnitine therapy, and with a matched population. RESULTS: Carnitine therapy at a mean dose of 1.5 +/- 0.7 g per administration for an average of 9.7 +/- 5.4 months was associated with a significant reduction in hospital utilization. Patients with cardiovascular disease, defined as hospitalizations for angina, myocardial infarction, arrhythmia, congestive heart failure, cerebral vascular disease or peripheral vascular disease prior to receiving carnitine, and those with anemia and hypoalbuminemia derived the greatest benefit from carnitine therapy. In a multivariate analysis, compared to 3 months prior to the initiation of carnitine, the adjusted relative risk for hospitalization was 11, 11, and 15% lower at 3, 6, and 9 months, respectively. Among patients with cardiovascular disease, the reduction in risk was even more significant (24, 31, and 34% lower at 3, 6, and 9 months, respectively). Similar results were observed with adjusted relative risk for hospital days. CONCLUSION: Administration of L-carnitine to chronic hemodialysis patients is associated with lower hospital utilization.

Adolescent↗
PubMed2005

Levocarnitine and dialysis: a review.

Among the various metabolic abnormalities documented in dialysis patients are abnormalities related to the metabolism of fatty acids. Aberrant fatty-acid metabolism has been associated with the promotion of free-radical production, insulin resistance, and cellular apoptosis. These processes have been identified as important contributors to the morbidity experienced by dialysis patients. There is evidence that levocarnitine supplementation can modify the deleterious effects of defective fatty-acid metabolism. Patients receiving hemodialysis and, to a lesser degree, peritoneal dialysis have been shown to be carnitine deficient, as manifested by reduced levels of plasma free carnitine and an increase in the acyl:free carnitine ratio. Cardiac and skeletal muscles are particularly dependent on fatty-acid metabolism for the generation of energy. A number of clinical abnormalities have been correlated with a low plasma carnitine status in dialysis patients. Clinical trials have examined the efficacy of levocarnitine therapy in a number of conditions common in dialysis patients, including skeletal-muscle weakness and fatigue, cardiomyopathy, dialysis-related hypotension, hyperlipidemia, and anemia poorly responsive to recombinant human erythropoietin therapy (rHuEPO). This review examines the evidence for carnitine deficiency in patients requiring dialysis, and documents the results of relevant clinical trials of levocarnitine therapy in this population. Consensus recommendations by expert panels are summarized and contrasted with present guidelines for access to levocarnitine therapy by dialysis patients.

Carnitine↗
PubMed2005

Carnitine levels in valproic acid-treated psychiatric patients: a cross-sectional study.

BACKGROUND: Carnitine facilitates the transport of long-chain fatty acids across the mitochondria for beta oxidation, and the removal of potentially toxic acylcoenzyme-A metabolites from the inner aspect of mitochondrion as acylcarnitines. Previous studies suggest a significant decrease in carnitine concentrations and changes in the ratio of acylcarnitine to free carnitine in seizure-disoriented patients treated with valproic acid (VPA), which may lead to clinical manifestations of carnitine deficiency. This study sought to explore whether the same decrease in plasma free carnitine and increase in acylcarnitines are seen when VPA is used in the treatment of patients with psychiatric disease. METHOD: Thirty psychiatric patients treated with VPA for at least six months were selected for the study and granted informed consent for participation. Exclusion criteria included liver disorder or pancreatitis, metabolic defects known to affect plasma carnitine levels, or noncompliance with VPA regimen. Plasma free carnitine, total carnitine, VPA, and amylase levels were determined, and liver function tests (LFTs) were performed. Pearson correlations were conducted between VPA levels, levels and ratios of carnitines, as well as LFTs and amylase levels. RESULTS: Plasma free and total carnitine levels were lower than the reported normal range for the laboratory performing the assay, and the ratio of acylcarnitine to free carnitine was increased. There was a significant positive correlation of VPA levels and acylcarnitine-free carnitine ratio, a trend toward significance between VPA levels and acylcarnitine levels, and a marginal negative correlation between VPA levels and free carnitine levels. VPA levels correlated also with several LFTs and acylcarnitine levels. Octanoyl carnitine and acylcarnitine levels, as well as acylcarnitine-free carnitine and octanoyl-free carnitine ratios, correlated significantly with amylase levels. CONCLUSION: Although the study was limited by a cross-sectional design without direct control comparison, the findings suggest that patients with various psychiatric conditions treated with polypharmacy that includes VPA may have lower plasma carnitine levels than would be expected in healthy controls.

Adult↗