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1.
Leuk Lymphoma ; 63(9): 2224-2232, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35475716

RESUMO

Despite a favorable effect of imatinib on glucose metabolism in animal models, human reports are inconsistent. We retrospectively studied the long-term effect of imatinib on fasting plasma glucose (FPG), glycated hemoglobin (HbA1C), LDL-cholesterol (LDL), and triglycerides (TGs) in a large HMO cohort of patients initiating therapy. In patients with diabetes (n = 118), significant reductions in HbA1c (0.53%, IQR 0.09, 1.19; p < .001) and FPG (10.2 mg/dL, IQR -3.5, 32.2; p < .001), independent of demographics and of glucose-lowering drugs utilization, were observed during the first year of imatinib treatment. Significant reductions in LDL (17.8 mg/dL, IQR -1.3, 34.0; p < .001) and TG (25.0 mg/dL, IQR -2.3, 58.3; p < .001), also independent of demographics and of statin utilization, were evident in the entire cohort (n = 611) during the first imatinib year. All reductions persisted during the second treatment year. To conclude, imatinib is associated with durable metabolic benefits, which may guide TKI choice in patients with cardiovascular co-morbidities.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores de Hidroximetilglutaril-CoA Redutases , Glicemia , LDL-Colesterol/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas/análise , Hemoglobinas Glicadas/metabolismo , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Mesilato de Imatinib/efeitos adversos , Estudos Retrospectivos , Triglicerídeos/uso terapêutico
2.
J Oncol Pharm Pract ; 28(2): 508-515, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34668443

RESUMO

INTRODUCTION: Acute kidney injury (AKI) after high dose methotrexate (HD-MTX) is associated with delayed MTX-excretion and life-threatening toxicity. Glucapridase, the recommended therapy, is expensive and not always available. CASE SERIES: We describe 3 cases (69, 67, 73 years) with diffuse large B-cell lymphoma who developed AKI and early-onset severely delayed MTX elimination after HD-MTX. MTX serum concentrations were 101 and 69 µmol/L at 24 h after administration in two patients and 34 µmol/L at 32 h in the third. MANAGEMENT AND OUTCOME: Since glucarpidase was unavailable, we performed daily high-flux hemodialysis (HF-HD) or online hemodiafiltration (HDF) sessions (median duration, 6 h). The median serum MTX elimination half-life during HDF/HF-HD sessions was similar in all patients (median, 4.4 h; IQR, 3.8-5.3 h), but serum MTX concentrations rebounded after each dialysis by a median of 40% of the trough concentrations. The three patients underwent multiple dialysis sessions, until MTX serum concentrations remained sufficiently low to be neutralized by leucovorin. Only 1 patient developed severe pancytopenia, and renal function normalized in all patients after 3-6 weeks. DISCUSSION: In conclusion, when glucarpidase is unavailable or delayed, early, repeated and prolonged HDF/HF-HD effectively enhance MTX elimination and prevent toxicity in patients with AKI and severely delayed MTX elimination after HD-MTX.


Assuntos
Injúria Renal Aguda , Hemodiafiltração , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/terapia , Antimetabólitos Antineoplásicos , Humanos , Metotrexato , Diálise Renal
3.
Ther Drug Monit ; 44(3): 414-418, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34739424

RESUMO

BACKGROUND: Busulfan (Bu) conditioning used in hematopoietic stem cell transplantation may induce seizures, and prophylactic antiepileptic treatment is recommended. Following updated guidelines, in August 2019, the adult hematopoietic stem cell transplantation department of the Rambam Health Care Campus (Haifa, Israel) switched the antiepileptic prophylaxis protocol from phenytoin to oral levetiracetam during oral Bu conditioning. The aim of this study was to compare the pharmacokinetic parameters of Bu after oral dosing between patients receiving phenytoin and those receiving levetiracetam prophylaxis. METHODS: This study was a retrospective cohort study in adults undergoing myoablative conditioning with oral Bu between August 2018 and August 2020. Bu pharmacokinetic parameters (AUC0-6, C0, Cmax, and Tmax) were compared in patients treated with phenytoin comedication (during the year before the change in policy) and levetiracetam comedication (during the year after the change). Potential confounders were accounted for including age, azole comedication, and body weight. RESULTS: There were no significant differences in demographic and clinical parameters or weight-corrected Bu dose between the phenytoin group (n = 28) and the levetiracetam group (n = 25). There was no difference in the rate of voriconazole comedication, but fluconazole was more common in the phenytoin group (P = 0.026). The median AUC0-6 was significantly lower in the levetiracetam group (949 µM*min; IQR = 806 to 1101 µM*min) than in the phenytoin group (1208 µM*min; IQR = 1087 to 1389 µM*min; P < 0.001). This is a clinically significant difference of 258 µM*min (21%). Azole use was not associated with Bu exposure. CONCLUSIONS: The findings suggest that, after treatment with oral Bu, oral levetiracetam comedication is associated with reduced systemic exposure compared with phenytoin comedication, possibly because of decreased bioavailability.


Assuntos
Bussulfano , Transplante de Células-Tronco Hematopoéticas , Adulto , Anticonvulsivantes , Bussulfano/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Levetiracetam/uso terapêutico , Fenitoína , Estudos Retrospectivos , Condicionamento Pré-Transplante/métodos
4.
Isr Med Assoc J ; 23(7): 426-431, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34251125

RESUMO

BACKGROUND: Decisions on medication treatment in children dying from cancer are often complex and may result in polypharmacy and increased medication burden. There is no information on medication burden in pediatric cancer patients at the end of life (EOL). OBJECTIVES: To characterize medication burden during the last hospitalization in children dying from cancer. METHODS: We performed a retrospective cohort study based on medical records of 90 children who died from cancer in hospital between 01 January 2010 and 30 December 2018. Demographic and clinical information were collected for the last hospitalization. We compared medication burden (number of medication orders) at hospitalization and at time of death and examined whether changes in medication burden were associated with clinical and demographic parameters. RESULTS: Median medication burden was higher in leukemia/lymphoma patients (6 orders) compared to solid (4 orders) or CNS tumor patients (4 orders, P = 0.006). Overall, the median number of prescriptions per patient did not change until death (P = 0.42), while there was a significant reduction for some medication subgroups (chemotherapy [P = 0.035], steroids [P = 0.010]).Patients dying in the ICU (n=15) had a higher medication burden at death (6 orders) than patients dying on wards (3 orders, P = 0.001). There was a trend for a reduction in medication burden in patients with "Do not resuscitate" (DNR) orders (P = 0.055). CONCLUSIONS: Polypharmacy is ubiquitous among pediatric oncology patients at EOL. Disease type and DNR status may affect medication burden and deprescribing during the last hospitalization.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias , Cuidados Paliativos , Polimedicação , Esteroides/uso terapêutico , Assistência Terminal , Criança , Procedimentos Clínicos/estatística & dados numéricos , Demografia , Feminino , Pesquisa sobre Serviços de Saúde , Hospitalização/estatística & dados numéricos , Humanos , Israel/epidemiologia , Masculino , Estadiamento de Neoplasias , Neoplasias/tratamento farmacológico , Neoplasias/mortalidade , Neoplasias/patologia , Cuidados Paliativos/métodos , Cuidados Paliativos/estatística & dados numéricos , Ordens quanto à Conduta (Ética Médica) , Assistência Terminal/métodos , Assistência Terminal/estatística & dados numéricos
5.
Am J Health Syst Pharm ; 78(9): 794-799, 2021 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-33617629

RESUMO

PURPOSE: To report a case of ribavirin-associated severe hyperuricemia in an immunocompromised patient treated for respiratory syncytial virus (RSV) infection. SUMMARY: A 21-year-old male with a past medical history of B-cell acute lymphoblastic leukemia was in full remission after allogenic bone marrow transplantation complicated with chronic graft-versus-host disease. He was hospitalized due to fever, malaise, and respiratory symptoms. A diagnosis of RSV upper respiratory tract infection complicated by secondary pneumonia was made, and oral ribavirin (600 mg in 3 divided doses daily) and intravenous levofloxacin (750 mg once daily) were initiated. On day 2 of the hospital admission, the patient's uric acid levels had increased from a baseline of 4 to 6 mg/dL to 19.3 and 22.2 mg/dL after the fourth and fifth doses of ribavirin, respectively, and his serum creatinine steadily had increased from a baseline of 0.7 to 0.8 mg/dL to 1.6 mg/dL. Ribavirin was discontinued after the sixth dose, and a single dose of intravenous rasburicase (7.5 mg) was administered. On day 3, the patient's serum uric and creatinine concentrations had decreased to 4.7 mg/dL and 1.1 mg/dL, respectively. He continued to recover on antibiotics and was discharged with normal uric acid and serum creatinine levels. CONCLUSION: We report a case of severe hyperuricemia and acute kidney injury that developed early after initiation of ribavirin for RSV infection and suspected bacterial pneumonia in an immunocompromised patient without hepatitis C, requiring ribavirin discontinuation and rasburicase administration. To our knowledge, this is the first reported case of severe hyperuricemia in a patient treated with ribavirin for RSV infection rather than chronic hepatitis C. Clinicians should be aware of the possibility of acute and severe hyperuricemia following ribavirin administration.


Assuntos
Injúria Renal Aguda , Hiperuricemia , Adulto , Creatinina , Humanos , Hiperuricemia/induzido quimicamente , Hiperuricemia/diagnóstico , Hiperuricemia/tratamento farmacológico , Masculino , Ribavirina/efeitos adversos , Ácido Úrico , Adulto Jovem
6.
Ther Drug Monit ; 42(3): 427-434, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31479045

RESUMO

BACKGROUND: Therapeutic drug monitoring (TDM) for busulfan supports dose adjustment during conditioning for stem cell transplantation. The authors aimed to develop and validate limited sampling strategies (LSS) of 4-5 samples for a precise estimation of the area under concentration (AUC)-time curve of busulfan, in plasma as an alternative to an intensive sampling strategy (ISS) requiring 9-10 samples. METHODS: ISS TDM data from 297 patients (≤18 years of age) were used. AUCLSS was calculated using the trapezoidal rule and multiple linear regression (MLR). Unlike more complex modeling methods, MLR does not require sophisticated software or advanced training of personnel. MLR coefficients were estimated in the development subset containing randomly selected 50% of the records and were then used to calculate the AUCLSS of the remaining records (the validation subset). The agreement between dose adjustment recommendations (DAR) based on ISS and LSS, in the validation subset, was evaluated by a Bland-Altman analysis. A DAR deviating from an ISS-based reference by <15% was deemed acceptable. RESULTS: Twelve LSSs were acceptable. Sampling at 0, 120, 180, and 240 minutes after the start of the second infusion (LSS15) yielded the best performance, with DAR deviating from the reference by <10% for 95% of cases; the AUCLSS was determined as follows: AUCLSS = 74.7954 × C(0) + 81.8948 × C(120) + 38.1771 × C(180) + 138.1404 × C(240) + 54.1837. This LSS and LSS13 performed similarly well in an independent external validation. CONCLUSIONS: MLR-based estimates of AUCLSS provide DARs that deviate minimally from the reference. LSSs allow the reduction of patient discomfort, a ∼50% reduction of TDM-related workload for nursing staff and blood loss and a ∼25% reduction in laboratory workload. These benefits may encourage wider use of busulfan TDM, supporting safe and efficacious personalized dosing.


Assuntos
Bussulfano/sangue , Monitoramento de Medicamentos/métodos , Imunossupressores/sangue , Adolescente , Fatores Etários , Área Sob a Curva , Superfície Corporal , Peso Corporal , Bussulfano/administração & dosagem , Bussulfano/farmacocinética , Criança , Pré-Escolar , Relação Dose-Resposta a Droga , Feminino , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/farmacocinética , Modelos Lineares , Masculino , Fatores Sexuais
7.
Age Ageing ; 49(1): 26-31, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31711101

RESUMO

BACKGROUND: little is known on the clinical implications of vancomycin trough levels among older patients. OBJECTIVE: to evaluate the association between vancomycin levels and outcomes among older versus younger patients. DESIGN: retrospective study. SUBJECTS: patients aged 18-64 and ≥65 years treated with vancomycin for documented methicillin resistant Staphylococcus aureus (MRSA) infections. METHODS: we compared the effectiveness and toxicity of vancomycin according to trough levels in older versus younger patients. Subgroup analysis of patients with glomerular filtration rate (GFR) > 60 ml/min/1.73 m2 was performed. RESULTS: we included 181 patients aged ≥65 years and 104 younger patients. Mean age in the older group was 76.9 ± 8 years versus 50.9 ± 12.4 in the younger group. Vancomycin trough levels and 24-hours area under the curve to minimal inhibitory concentrations (AUC/MIC) were significantly higher in older patients who were also significantly more likely to achieve trough levels of ≥15 mg/l within 4 days, (98/181 (54.1%) vs. 38/104 (36.5%) in younger patients, P = 0.004). Results were similar among patients with GFR > 60. Thirty-day mortality was significantly higher in older (74/181, 40.9% vs. 13/104, 12.5%, respectively, P < 0.001). There was no association between vancomycin trough levels and mortality among older patients. No significant differences were demonstrated in clinical or microbiological success or nephrotoxicity. CONCLUSIONS: applying uniform dosing recommendations across age groups among adults with MRSA infections results in higher vancomycin levels and AUC/MIC in older versus younger patients. Yet, mortality rates remain higher among older adults. Prospective studies are needed to define the optimal approach for using this drug in older patients.


Assuntos
Antibacterianos/administração & dosagem , Vancomicina/administração & dosagem , Adolescente , Adulto , Fatores Etários , Idoso , Antibacterianos/efeitos adversos , Antibacterianos/sangue , Feminino , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Retrospectivos , Infecções Estafilocócicas/tratamento farmacológico , Vancomicina/efeitos adversos , Vancomicina/sangue , Adulto Jovem
8.
Artigo em Inglês | MEDLINE | ID: mdl-27651890

RESUMO

BACKGROUND: Modern drug therapy accounts for a major share of health expenditure and challenges public provider resources. The objective of our study was to compare drug expenditure trends for ten major drug classes over 16 years at Maccabi Healthcare Services (MHS), the 2(nd) largest healthcare organization in Israel. METHODS: A retrospective analysis of drug expenditure per HMO beneficiary between the years 1998-2014. Trends in annual mean drug expenditures per MHS member were compared among 10 major drug classes. RESULTS: Average annual drug expenditure per beneficiary increased during the study period from 429.56 to 474.32 in 2014 (10.4 %). Ten drug classes accounted for 58.0 % and 77.8 % of total drug cost in 1998 and 2014, respectively. The overall distribution of drug expenditure among drug classes differed significantly between 1998 and 2014 (p < 0.001), mainly due to the increase in expenditure for cancer drugs, from 6.8 % of total drug cost to 30.3 %. In contrast, expenditures for cardiovascular drugs decreased during the same period from 16.0 to 2.7 %. Moreover, the median annual increase in net drug costs per HMO member during 1998-2014 was largest for cancer drugs (NIS 6.18/year; IQR, 1.70-9.92/year), about two-fold that of immunosuppressants, the second fastest growing drug class (NIS 2.81; IQR, 0.58-7.43/year). CONCLUSIONS: The continuous rise in anti-cancer drug expenditure puts a substantial burden on the medication budgets of public health organizations. Coordinated measures involving policy makers, physicians, and pharmaceutical companies will be required for efficient cost containment.

9.
Am Heart J ; 167(1): 101-108.e1, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24332148

RESUMO

BACKGROUND: Postoperative atrial fibrillation (PoAF) after cardiac surgery is common and associated with increased morbidity and mortality. Increased sympathetic activation after surgery contributes to PoAF, and ß-blockers are the first-line recommendation for its prevention. We examined the hypothesis that common functional genetic variants in the ß1-adrenoreceptor, the mediator of cardiac sympathetic activation and drug target of ß-blockers, are associated with the risk for PoAF and with the protective effect of ß-blockers. METHODS: In a prospective cohort study, we studied 947 adult European Americans who underwent cardiac surgery at Vanderbilt University between 1999 and 2005. We genotyped 2 variants in the ß1-adrenoreceptor, rs1801253 (Arg389Gly) and rs1801252 (Ser49Gly), and used logistic regression to examine the association between genotypes and PoAF occurring within 14 days after surgery, before and after adjustment for demographic and clinical covariates. RESULTS: Postoperative atrial fibrillation occurred in 239 patients (25.2%) and was associated with rs1801253 genotype (adjusted P = .008), with Gly389Gly having an odds ratio of 2.63 (95% CI 1.42-4.89) for PoAF compared to the common Arg389Arg (P = .002). In a predefined subgroup analysis, this association appeared to be stronger among patients without ß-blocker prophylaxis (adjusted odds ratio 7.00, 95% CI 1.82-26.96, P = .005) compared to patients with ß-blocker prophylaxis, among whom the association between rs1801253 genotype and PoAF was not statistically significant (adjusted P = .11). CONCLUSION: The Gly389 variant in the ß1-adrenoreceptor is associated with PoAF, and this association appears to be modulated by ß-blocker therapy. Future studies of the association of other adrenergic pathway genes with PoAF will be of interest.


Assuntos
Fibrilação Atrial/genética , Variação Genética , Complicações Pós-Operatórias/genética , Receptores Adrenérgicos beta 1/genética , Adulto , Idoso , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/cirurgia , Procedimentos Cirúrgicos Cardíacos , Genótipo , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Complicações Pós-Operatórias/prevenção & controle , Estudos Prospectivos , Fatores de Risco , População Branca/genética
11.
Pharmacogenet Genomics ; 22(4): 254-60, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22258110

RESUMO

OBJECTIVE: To examine the hypothesis that genetic variation in enzymes and transporters associated with synthesis, storage, release, and metabolism of catecholamines contributes to the interindividual variability in plasma catecholamine concentrations at rest and after exercise. METHODS: We measured plasma norepinephrine (NE) and epinephrine concentrations at rest and after a standardized exercise protocol in 165 healthy individuals (60% White, 40% African-American) and examined 29 functional or common variants in 14 genes involved in synthesis, transport, or metabolism of catecholamines. We examined the relationship between genotypes and NE concentrations at rest and the increase after exercise (ΔNE) by multiple linear regression with adjustment for covariates [age, race, sex, BMI, fitness, and resting NE (for ΔNE)]. As a secondary outcome, we carried out similar analyses for epinephrine concentrations. RESULTS: There was large interindividual variability in resting NE (mean, 204±102 pg/ml; range, 39-616 pg/ml) and ΔNE (mean, 256±206 pg/ml; range, -97 to 953 pg/ml). Resting NE was significantly associated with variants of four genes: CYB561 (P<0.001), VMAT2 (P=0.016), CHGA (P=0.039), and PNMT (P=0.038). ΔNE after exercise was associated with three variants of PNMT (P=0.041) and COMT (P=0.033 and 0.035), and resting and exercise epinephrine concentrations were associated with two variants each. CONCLUSION: The findings of this exploratory study suggest that variation in catecholamine pathway genes contributes to the interindividual variability in plasma NE and epinephrine concentrations at rest and after exercise.


Assuntos
Catecolaminas/genética , Epinefrina/sangue , Redes e Vias Metabólicas , Norepinefrina/sangue , Adulto , População Negra/genética , Catecolaminas/biossíntese , Catecolaminas/metabolismo , Cromogranina A/genética , Ensaios Clínicos como Assunto , Grupo dos Citocromos b/genética , Exercício Físico/fisiologia , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Descanso/fisiologia , Proteínas Supressoras de Tumor/genética , Proteínas Vesiculares de Transporte de Monoamina/genética , População Branca/genética
12.
Eur J Clin Pharmacol ; 68(6): 937-42, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22271297

RESUMO

PURPOSE: There is a large interindividual variability in dexmedetomidine dose requirements for sedation of patients in intensive care units (ICU). Cytochrome P450 2A6 (CYP2A6) mediates an important route of dexmedetomidine metabolism, and genetic variation in CYP2A6 affects the clearance of other substrate drugs. We examined whether CYP2A6 genotypes affect dexmedetomidine disposition. METHODS: In 43 critically ill ICU patients receiving dexmedetomidine infusions adjusted to achieve the desired level of sedation, we determined a median of five plasma dexmedetomidine concentrations each. Forty subjects were genotyped for five common CYP2A6 alleles and grouped into normal (n = 33), intermediate (n = 5), and slow metabolizers (n = 2). RESULTS: Using a Bayesian hierarchical nonlinear mixture model, estimated dexmedetomidine clearance was 49.1 L/h (posterior mean; 95% credible interval 41.4-57.6 L/h). There were no significant differences in dexmedetomidine clearance among normal, intermediate, and slow CYP2A6 metabolizer groups. CONCLUSION: Genetic variation in CYP2A6 does not appear to be an important determinant of dexmedetomidine clearance in ICU patients.


Assuntos
Hidrocarboneto de Aril Hidroxilases/genética , Dexmedetomidina/farmacocinética , Hipnóticos e Sedativos/farmacocinética , Alelos , Hidrocarboneto de Aril Hidroxilases/metabolismo , Teorema de Bayes , Citocromo P-450 CYP2A6 , Dexmedetomidina/sangue , Feminino , Variação Genética , Genótipo , Humanos , Hipnóticos e Sedativos/sangue , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade
13.
J Pharmacokinet Pharmacodyn ; 38(5): 613-36, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21847635

RESUMO

The purpose of this study is to develop a statistical methodology to handle a large proportion of artifactual outliers in a population pharmacokinetic (PK) modeling. The motivating PK data were obtained from a population PK study to examine associations between PK parameters such as clearance of dexmedetomidine (DEX) and cytochrome P450 2A6 phenotypes. The blood samples were sparsely sampled from patients in intensive care units (ICUs) while different doses of DEX were continuously infused. Conventional population PK analysis of these data revealed several challenges and intricacies. Especially, there was strong evidence that some plasma drug concentrations were artifactually high and likely contaminated with the infused drug due to blood sampling processes that are sometimes unavoidable in an ICU setting. If not addressed, or if arbitrarily excluded, these outlying values could lead to biased estimates of PK parameters and miss important relationships between PK parameters and covariates due to increased variability. We propose a novel population PK model, a Bayesian hierarchical nonlinear mixture model, to accommodate the artifactual outliers using a finite mixture as the residual error model. Our results showed that the proposed model handles the outliers well. We also conducted simulation studies with a varying proportion of the outliers. These simulation results showed that the proposed model can accommodate the outliers well so that the estimated PK parameters are less biased.


Assuntos
Simulação por Computador , Dexmedetomidina/farmacocinética , Hipnóticos e Sedativos/farmacocinética , Dinâmica não Linear , Hidrocarboneto de Aril Hidroxilases/sangue , Hidrocarboneto de Aril Hidroxilases/genética , Teorema de Bayes , Citocromo P-450 CYP2A6 , Dexmedetomidina/sangue , Relação Dose-Resposta a Droga , Humanos , Hipnóticos e Sedativos/sangue , Projetos de Pesquisa , Estatística como Assunto
14.
Breast Cancer Res Treat ; 125(2): 505-10, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20593233

RESUMO

Endoxifen, the most active metabolite of the prodrug tamoxifen, is produced by cytochrome P450 CYP2D6. Breast cancer patients treated with tamoxifen who have reduced CYP2D6 activity, related to either genetic variation or drug inhibition, may have inferior outcomes. To assess the effect of concomitant CYP2D6 inhibiting drug use on clinical outcomes of breast cancer patients treated with adjuvant tamoxifen. We conducted a retrospective database analysis. Women with non-metastatic estrogen receptor positive tumors who had completed adjuvant tamoxifen therapy for 2 years, without treatment with adjuvant aromatase inhibitors or early relapse, were included. Patients were classified as users of CYP2D6 inhibitors if they purchased strong CYP2D6 inhibiting drugs for ≥ 4 consecutive months during tamoxifen treatment. Tumors were classified as "high risk" if adjuvant chemotherapy was prescribed. Primary endpoint was disease free (DFS) and secondary endpoint was overall survival (OS). 902 patients treated with tamoxifen (median duration, 4.9 years) were followed for a median period of 5.9 years. Fifty-nine (6.5%) patients were users of CYP2D6 inhibitors (median duration, 23 months). DFS at 3 years (corresponding to 5 years after tamoxifen initiation) did not differ between users and non-users of CYP2D6 inhibiting drugs (92.7 vs. 93.0%, respectively; adjusted P = 0.44). OS at 3 years was lower in the patients using CYP2D6 inhibiting drugs: 89.4 vs. 93.8%, but after adjustment for age and comorbidities this difference was not significant (P = 0.20). Overall recurrence rates did not differ between users and non-users of CYP2D6 inhibiting drugs (11.8 vs. 19.0% respectively, P = 0.23). Concomitant prolonged therapy with strong CYP2D6 inhibiting drugs does not affect adversely DFS and recurrence rates in tamoxifen-treated early breast cancer patients.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Inibidores do Citocromo P-450 CYP2D6 , Inibidores Enzimáticos/uso terapêutico , Tamoxifeno/uso terapêutico , Idoso , Antineoplásicos Hormonais/administração & dosagem , Neoplasias da Mama/metabolismo , Quimioterapia Adjuvante , Intervalo Livre de Doença , Interações Medicamentosas , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estudos Retrospectivos , Tamoxifeno/administração & dosagem , Tamoxifeno/análogos & derivados , Tamoxifeno/metabolismo , Resultado do Tratamento
15.
Biol Blood Marrow Transplant ; 17(1): 117-23, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20601034

RESUMO

High-dose busulfan (Bu) is frequently used in preparative myeloablative conditioning (MAC) regimens for patients undergoing hematopoietic stem cell transplantation (HSCT). MAC and reduced-intensity conditioning (RIC) protocols for i.v. Bu infusion have been developed to achieve reliable systemic exposure while minimizing toxicity and treatment failure (relapse). The objectives of the present study were to (1) compare the pharmacokinetics (PK) of i.v. Bu in different dosing protocols, (2) compare intrasubject variability of Bu PK over repeated administrations; (3) examine the effect of concomitant administration of fludarabine on Bu PK, and (4) examine the effect of plasma concentrations of glutathione (GSH), the cosubstrate in Bu metabolism, on Bu clearance. We studied Bu PK twice in each of 46 HSCT patients (after the first and then after the middle dose of the treatment cycle) receiving one of 4 dosing protocols, 2 MAC (cumulative dose, 12.8 mg/kg) and 2 RIC (cumulative dose, 6.4 mg/kg), with daily doses administered either as an individual infusion (3.2 mg/kg) or as 4 infusions of 0.8 mg/kg each. Blood samples were obtained for 6-24 hours after dosing for measurement of Bu plasma concentrations. PK parameters were estimated using compartmental analyses. In a subgroup of patients (n = 14), GSH blood concentrations were determined before Bu administration. Dose- and weight-corrected Bu PK parameters (clearance, 0.173 ± 0.051 L/hour · kg; volume of distribution, 0.71 ± 0.17 L/kg; half-life time, 3.0 ± 0.7 hours) did not differ among treatment protocols (all P >.14) and remained stable between the first and mid-cycle doses. Fludarabine did not affect Bu PK. Blood GSH concentrations before Bu dosing were positively correlated with Bu clearance (adjusted R(2) = 0.45; P = .009). Our data indicate that Bu PK parameters are linear, stable, and predictable in different i.v. protocols and are unaffected by coadministration of fludarabine. Differences in whole blood GSH might contribute to variability in Bu clearance.


Assuntos
Bussulfano/farmacocinética , Glutationa/sangue , Transplante de Células-Tronco Hematopoéticas/métodos , Adulto , Idoso , Bussulfano/administração & dosagem , Bussulfano/metabolismo , Relação Dose-Resposta a Droga , Interações Medicamentosas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Agonistas Mieloablativos/uso terapêutico , Farmacocinética , Medicina de Precisão , Reprodutibilidade dos Testes , Vidarabina/administração & dosagem , Vidarabina/análogos & derivados , Adulto Jovem
16.
J Rheumatol ; 35(7): 1314-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18528966

RESUMO

OBJECTIVE: Cardiovascular mortality is increased in systemic lupus erythematosus (SLE). Increased plasma concentrations of N-terminal pro-brain natriuretic peptide (NT-proBNP) are associated with cardiovascular morbidity and mortality in the general population. We examined the hypothesis that NT-proBNP concentrations are higher in patients with SLE, and are related to inflammation, augmentation index, coronary atherosclerosis, and cardiovascular risk factors. METHODS: Serum concentrations of NT-proBNP were measured in 113 patients with SLE and in 80 control subjects. Coronary calcification and augmentation index were measured by electron beam computed tomography and noninvasive pulse wave analysis, respectively. RESULTS: Patients with SLE had higher concentrations of NT-proBNP [median 38.6 (interquartile range 2.5-126.9) pg/ml] than controls [11.7 (1.6-47.9) pg/ml] (p = 0.002). Augmentation index was higher in patients with SLE [25.0% (20.5%-31.5%)] than controls [20.5% (12.0%-29.0%)] (p = 0.04). In patients with SLE, NT-proBNP concentrations were associated with disease damage (rho = 0.31, p < 0.001) and duration (rho = 0.21, p = 0.02) but not with disease activity, C-reactive protein, erythrocyte sedimentation rate, tumor necrosis factor-alpha, interleukin 6, coronary calcium score, or augmentation index (all p > or = 0.18). CONCLUSION: Patients with SLE have increased concentrations of NT-proBNP, but this is not explained by atherosclerotic burden, augmentation index, or inflammatory state.


Assuntos
Calcinose/sangue , Doença da Artéria Coronariana/sangue , Lúpus Eritematoso Sistêmico/sangue , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Calcinose/complicações , Estudos de Casos e Controles , Colonografia Tomográfica Computadorizada , Doença da Artéria Coronariana/complicações , Elasticidade , Feminino , Humanos , Lúpus Eritematoso Sistêmico/complicações , Masculino , Fluxo Pulsátil
17.
J Rheumatol ; 34(12): 2388-94, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18050386

RESUMO

OBJECTIVE: Arterial stiffness, assessed by the augmentation index and pulse wave velocity, is an independent risk factor for cardiovascular disease. Rheumatoid arthritis (RA) is associated with accelerated atherosclerosis and increased cardiovascular mortality. We examined the hypothesis that augmentation index and pulse wave velocity are increased in RA, and are related to coronary artery atherosclerosis. METHODS: We measured augmentation index and brachial pulse wave velocity in 117 patients with RA [57 with early (< 6 yrs) and 60 with late disease (> 10 yrs)] and 65 healthy controls. Coronary artery calcification was measured by electron beam computed tomography. Augmentation index and pulse wave velocity were compared in patients with early RA, late RA, and controls, and the association with coronary atherosclerosis was examined. RESULTS: Patients with late RA had a higher augmentation index (median 33.8%, interquartile range 27.5% 37.0%) than those with early disease (median 27.5%, IQR 21.0% 34.0%) (p = 0.008) and controls (median 27.0%, IQR 20.4% 33.0%) (p < 0.001). After adjusting for height and cardiovascular risk factors, the association between late disease and augmentation index remained significant (p = 0.02). Augmentation index was associated with coronary calcification score (rs = 0.19, p = 0.046), and the association was marginal after adjustment for cardiovascular risk factors, disease status, and disease activity (p = 0.09). There was no significant difference in brachial pulse wave velocity among patients with late (9.2 +/- 1.7 m/s) and early RA (9.1 +/- 1.6 m/s) and controls (8.9 +/- 1.5 m/s) (p = 0.78). CONCLUSION: Patients with RA have increased augmentation index independent of cardiovascular risk factors. Augmentation index was associated with coronary artery calcification in patients with RA; this was attenuated after adjusting for cardiovascular risk factors.


Assuntos
Artrite Reumatoide/fisiopatologia , Artéria Braquial/fisiopatologia , Calcinose/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Idoso , Artrite Reumatoide/complicações , Velocidade do Fluxo Sanguíneo , Estudos de Casos e Controles , Doença da Artéria Coronariana/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X
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