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1.
Endocr Pract ; 29(8): 601-605, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37149036

RESUMO

OBJECTIVE: Bisphosphonate treatment does not increase bone mineral density (BMD) in all subjects particularly at the femoral neck (FN). Our aim was to evaluate the relationship between response to oral bisphosphonate (oBP) at the FN and change in BMD following discontinuation. METHODS: Data were collected retrospectively from postmenopausal women on oBP for ≥3 years, attending a real-world metabolic clinic at initiation of oBP, discontinuation, and 1 to 2 years post discontinuation. Improvement in BMD ≥4% in the FN and ≥5% for the lumbar spine (LS) were deemed clinically meaningful and used as least significant change (LSC) values. We divided subjects based on FN BMD response and compared outcomes between responders and non-responders after oBP discontinuation. RESULTS: Of the 213 subjects, 32.1% showed an increase ≥LSC at the FN compared to 57.1% at the LS on treatment (P < .0001). FN responders had lower BMD levels at pretreatment baseline than non-responders both at the FN (0.58 vs 0.62 g/cm2; P = .003) and LS (0.76 vs 0.79 g/cm2; P = .044). Off-treatment, more subjects lost BMD ≥LSC at FN in the responder group than in the non-responder group (37.5% vs 14.2%; P < .001). BMD remained above pre-treatment levels in responders after a median follow-up of 1.52 years. CONCLUSION: BMD response at FN is suboptimal in patients on oBP and is much less common than LS response. FN responders tend to lose the accumulated bone quickly off-treatment, though BMD remains above pretreatment levels. These observations suggest that new approaches may be needed to optimize osteoporosis management in real-world patients.


Assuntos
Conservadores da Densidade Óssea , Osteoporose Pós-Menopausa , Humanos , Feminino , Densidade Óssea , Difosfonatos/uso terapêutico , Estudos Retrospectivos , Conservadores da Densidade Óssea/uso terapêutico , Osso e Ossos , Vértebras Lombares/diagnóstico por imagem , Osteoporose Pós-Menopausa/tratamento farmacológico
2.
J Clin Densitom ; 26(1): 36-44, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36372621

RESUMO

PURPOSE: Describe fracture risk assessment practices among physicians treating osteoporosis in a real-life setting. METHODS: This is a retrospective cohort study in a tertiary academic center. Inclusion criteria involved adults (aged ≥18 years) who received minimum adequate therapy (bisphosphates, raloxifene, or denosumab ≥ 3 years or teriparatide ≥ 18 months). Of 1,814 charts randomly selected and reviewed, 274 patients met the inclusion criteria. Risk stratification tools included fragility fractures, Dual-energy X-ray Absorptiometry (DXA), and fracture risk assessment using the FRAX tool. Fracture risk assessment was performed before therapy initiation (N= 274) and at the time of institution of the drug holiday (N=119). High-risk patients were defined as the presence of a fragility fracture, T-score ≤-2.5, or a high-risk score by FRAX calculation. FRAX scores were independently calculated by the research team for comparison and assessment purposes. RESULTS: Before initiation of therapy (N=274) versus upon starting a drug holiday (DH; N=119), 29.9% versus 3.4% had a history of fragility fractures (P<0.001), 58.8% versus 67.2% had a DXA scan performed (P>0.05), 10.5% versus 10.9% of physicians calculated a FRAX score (P>0.05), and 71.5% versus 66.4% were considered at high risk and eligible for therapy. A DXA scan was performed after DH in 40.2% of these patients and at least once in 95.3% of the entire cohort. CONCLUSION: The reporting of FRAX score in DXA scan reports may significantly increase its utilization in fracture risk assessment. We recommend comprehensive fracture risk assessment utilizing history of prevalent osteoporosis fractures, DXA assessment, and FRAX scoring.


Assuntos
Osteoporose , Fraturas por Osteoporose , Adulto , Humanos , Adolescente , Densidade Óssea , Estudos Retrospectivos , Medição de Risco , Osteoporose/tratamento farmacológico , Osteoporose/epidemiologia , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Absorciometria de Fóton , Fatores de Risco
3.
Int J Mol Sci ; 24(9)2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37175614

RESUMO

Despite significant advances in targeted therapies against the hyperactivated BRAFV600/MEK pathway for patients with unresectable metastatic melanoma, acquired resistance remains an unsolved clinical problem. In this study, we focused on melanoma cells resistant to trametinib, an agent broadly used in combination therapies. Molecular and cellular changes were assessed during alternating periods of trametinib withdrawal and rechallenge in trametinib-resistant cell lines displaying either a differentiation phenotype (MITFhigh/NGFRlow) or neural crest stem-like dedifferentiation phenotype (NGFRhigh/MITFlow). Neither drug withdrawal nor drug rechallenge induced cell death, and instead of loss of fitness, trametinib-resistant melanoma cells adapted to altered conditions by phenotype switching. In resistant cells displaying a differentiation phenotype, trametinib withdrawal markedly decreased MITF level and activity, which was associated with reduced cell proliferation capacity, and induced stemness assessed as NGFR-positive cells and senescence features, including IL-8 expression and secretion. All these changes could be reversed by trametinib re-exposure, which emphasizes melanoma cell plasticity. Trametinib-resistant cells displaying a dedifferentiation phenotype were less responsive presumably due to the already low level of MITF, a master regulator of the melanoma phenotype. Considering new directions of the development of anti-melanoma treatment, our study suggests that the phenotype of melanomas resistant to targeted therapy might be a crucial determinant of the selection of second-line therapy for melanoma patients.


Assuntos
Interleucina-8 , Melanoma , Humanos , Interleucina-8/genética , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/patologia , Piridonas/farmacologia , Piridonas/uso terapêutico , Pirimidinonas/uso terapêutico , Fenótipo , Proteínas Proto-Oncogênicas B-raf/genética , Fator de Transcrição Associado à Microftalmia/genética , Fator de Transcrição Associado à Microftalmia/metabolismo , Proteínas do Tecido Nervoso/genética , Receptores de Fator de Crescimento Neural/genética
4.
Endocr Pract ; 28(10): 1078-1085, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35787466

RESUMO

OBJECTIVE: Published literature on physicians' preferences and sequential treatment patterns of osteoporosis therapy is scarce. METHODS: A retrospective cohort study of patients who received bisphosphonates, denosumab, and/or raloxifene for at least 3 consecutive years or teriparatide for at least 18 months for osteoporosis. Data collection spanned 10 years, from October 2007 to September 2016, at a tertiary care center in the United States. RESULTS: In total, 12 885 patients were identified on the basis of receiving at least 1 treatment at any point in time; 1814 patients were randomly reviewed, and 274 patients met the inclusion criteria. The mean age was 68.8 ± 10.7 years, and women represented 90.9% of all the cases. Primary care physicians and rheumatologists constituted 65.7% and 22.6% of the prescribers, respectively. Before instituting a drug holiday, alendronate was the most common initial treatment (percentage, mean duration ± standard deviation in years: 69%, 5.4 ± 2.4 years) followed by ibandronate (9.5%, 4.9 ± 2.1 years) and raloxifene (9.1%, 5.2 ± 1.6 years). Denosumab was the most common second course of treatment, accounting for 29.3% of 82 patients who were subsequently prescribed another therapy, followed by alendronate (24.4%) and zoledronate (20.7%). Among patients who were placed on a drug holiday and eventually restarted on osteoporosis therapy, denosumab was the most common treatment instituted (n = 21), accounting for 40% of the total patients, followed by alendronate (32%) and zoledronate (16%). There was a progressive decline in osteoporosis therapy over the duration of the study. CONCLUSION: Alendronate was the most common initial therapy. Denosumab was the most common second course of treatment prescribed.


Assuntos
Conservadores da Densidade Óssea , Osteoporose Pós-Menopausa , Osteoporose , Idoso , Alendronato/uso terapêutico , Denosumab/uso terapêutico , Difosfonatos/uso terapêutico , Feminino , Humanos , Ácido Ibandrônico/uso terapêutico , Pessoa de Meia-Idade , Osteoporose/tratamento farmacológico , Osteoporose Pós-Menopausa/tratamento farmacológico , Cloridrato de Raloxifeno/uso terapêutico , Estudos Retrospectivos , Teriparatida/uso terapêutico , Estados Unidos , Ácido Zoledrônico/uso terapêutico
5.
Osteoporos Int ; 32(11): 2323-2333, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33997909

RESUMO

Pre-existing inflammation, corticosteroid therapy, periapical periodontitis, longer duration of denosumab therapy, and female sex were significantly associated with an increased risk of denosumab-related osteonecrosis of the jaw after tooth extraction in patients with cancer on oncologic doses of denosumab. A short drug holiday did not protect against this complication. INTRODUCTION: This study retrospectively investigated the relationship between various risk factors, including brief discontinuation of denosumab, and development of denosumab-related osteonecrosis of the jaw (DRONJ) after tooth extraction in patients with cancer who were receiving oncologic doses of this agent. METHODS: Data were collected on demographic characteristics, duration of denosumab therapy, whether or not denosumab was discontinued before tooth extraction (drug holiday), duration of discontinuation, presence of pre-existing inflammation, and whether or not additional surgical procedures were performed. Risk factors for DRONJ after tooth extraction were evaluated by univariate and multivariate analyses. RESULTS: A total of 136 dental extractions were performed in 72 patients (31 men, 41 women) with cancer who were receiving oncologic doses of denosumab. Post-extraction DRONJ was diagnosed in 39 teeth (28.7%) in 25 patients. Tooth extraction was significantly associated with development of DRONJ only in patients with pre-existing inflammation (odds ratio [OR] 243.77), those on corticosteroid therapy (OR 73.50), those with periapical periodontitis (OR 14.13), those who had been taking oncologic doses of denosumab for a longer period (OR 4.69), and in women (OR 1.04). There was no significant difference in the occurrence of DRONJ between patients who had a drug holiday before tooth extraction and those who did not. CONCLUSIONS: These findings suggest that inflamed teeth should be extracted immediately in patients with cancer who are receiving oncologic doses of denosumab. Drug holidays have no significant impact on the risk of DRONJ.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos , Conservadores da Densidade Óssea , Neoplasias , Osteonecrose , Preparações Farmacêuticas , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/epidemiologia , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Conservadores da Densidade Óssea/efeitos adversos , Denosumab/efeitos adversos , Difosfonatos , Feminino , Humanos , Masculino , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Osteonecrose/induzido quimicamente , Osteonecrose/epidemiologia , Estudos Retrospectivos , Extração Dentária/efeitos adversos
6.
Curr Osteoporos Rep ; 19(2): 182-188, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33528743

RESUMO

PURPOSE OF REVIEW: This review describes the rational for bisphosphonate holidays, summaries key evidence to support the concept, and provides a roadmap to help clinicians initiate, monitor, and discontinue a bisphosphonate drug holiday. RECENT FINDINGS: Randomized trials and data from large observational studies are available to determine the short and long-term bisphosphonate benefits (prevention of fracture) and harms (principally atypical femoral fractures and osteonecrosis of the jaw). Mounting evidence points towards a causal relationship between bisphosphonate use and AFF and ONJ, particularly with > 5 years of use. Multiple studies now confirm the risk of AFF falls rapidly after BPs are discontinued. Osteoporosis patients without previous hip, vertebral, or multiple non-spine fractures who are successfully treated with oral bisphosphonates for 5 years (3 years if intravenous), should be offered a 3-5 year drug holiday, particularly if hip BMD T-score is > - 2.5. Bisphosphonates should only be continued beyond 10 years (6 years if parenteral) in patients at very high risk of fracture.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Esquema de Medicação , Osteoporose/tratamento farmacológico , Atenção Primária à Saúde , Humanos
7.
Nord J Psychiatry ; 75(5): 323-329, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33356759

RESUMO

OBJECTIVE: This study aimed to investigate the effects of drug holidays during summer vacations among children with attention deficit/hyperactivity disorder (ADHD) who were treated with methylphenidate in terms of ADHD symptoms and executive functions. METHODS: The study was a prospective cohort study that includes pre-treatment, post-treatment and post-drug holiday evaluations. ADHD symptom severity was evaluated with the Clinical Global Impression Scale (CGI), the Conners' Parental Rating Scale-Short Form (CPRS) and the Conners' Teacher Rating Scale- Short Form (CTRS). The Stroop Color Word Test- TBAG Form (SCWT) was used to evaluate executive functions. Fifty-one patients participated in the study according to the inclusion and exclusion criteria. Methylphenidate (MPH) was started at 0.5 mg/kg/day and titrated weekly to a maximum of 1.2 mg/kg/day. During the follow-up period, 22 (43.0%) of the patients stopped treatment. RESULTS: Completion times for all SCWT subtests were significantly reduced after treatment (p < 0.001, p = 0.002, p < 0.001, p = 0.002, p < 0.001; respectively). Mean number of corrections in SCWT-3 and mean number of errors as well as corrections in SCWT-5 significantly reduced after treatment (p = 0.047, p = 0.005, p = 0.007; respectively). Mean number of corrections in SCWT-3 and mean number of errors in SCWT-5 increased significantly after drug holiday compared to post-treatment (p = 0.032 and p = 0.037; respectively). CONCLUSION: Our results suggest that psychomotor speed and resistance to interference improved in children with ADHD receiving methylphenidate treatment. Drug holidays did not affect psychomotor speed while beneficial effects on resistance to interference were reduced with drug holidays.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Estimulantes do Sistema Nervoso Central , Metilfenidato , Preparações Farmacêuticas , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Estimulantes do Sistema Nervoso Central/uso terapêutico , Criança , Humanos , Metilfenidato/uso terapêutico , Estudos Prospectivos , Resultado do Tratamento
8.
Osteoporos Int ; 31(7): 1273-1282, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32020265

RESUMO

We performed a cost-effectiveness analysis comparing 5 versus 10 years of alendronate treatment prior to 5-year drug holiday for US postmenopausal women with hip BMD T-scores between - 2.5 and - 3.5. We found that for most postmenopausal women 5 years of treatment prior to drug holiday is the more effective and cost-effective option. INTRODUCTION: We performed a cost-effectiveness analysis to compare 5 versus 10 years of alendronate treatment prior to 5-year drug holiday for postmenopausal osteoporotic women. METHODS: We created an individual-level state-transition microsimulation model to compare 3 treatment strategies for US postmenopausal women with osteoporosis and femoral neck BMD T-scores between - 2.5 and - 3.5 at baseline: recurrent periods of 5 years of alendronate followed by 5 years of drug holiday (alendronate 5/5), recurrent periods of 10 years of alendronate followed by 5 years of drug holiday (alendronate 10/5), and no alendronate treatment. RESULTS: Base-case analysis revealed for women initiating treatment at ages 50, 60, and 70, the alendronate 5/5 strategy dominated (was more effective and less costly than) the alendronate 10/5 strategy and no treatment. For women age 80, the alendronate 10/5 strategy dominated. When assuming a lower relative risk of nonvertebral fracture during years 6-10 of alendronate treatment than the base-case assumption, the alendronate 10/5 strategy became the most cost-effective strategy even at younger treatment initiation ages. Probabilistic sensitivity analysis results supported the base-case findings; for treatment initiation ages of 50, 60, and 70, the alendronate 5/5 strategy was favored, whereas for treatment initiation age of 80, the alendronate 10/5 strategy was favored; however, there was uncertainty in these findings. CONCLUSIONS: After 5 years of alendronate treatment, younger postmenopausal women (ages 50-70) with osteoporosis would likely benefit from a drug holiday, whereas older women (age 80) are likely to benefit from treatment for 10 years before a drug holiday.


Assuntos
Alendronato/uso terapêutico , Conservadores da Densidade Óssea , Osteoporose Pós-Menopausa , Osteoporose , Preparações Farmacêuticas , Idoso , Idoso de 80 Anos ou mais , Alendronato/economia , Conservadores da Densidade Óssea/economia , Conservadores da Densidade Óssea/uso terapêutico , Análise Custo-Benefício , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/tratamento farmacológico , Anos de Vida Ajustados por Qualidade de Vida
9.
Osteoporos Int ; 30(1): 231-239, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30406309

RESUMO

Root amputation, immunosuppressive therapy, mandibular tooth extraction, pre-existing inflammation, and longer duration of treatment with bone-modifying agents were significantly associated with an increased risk of medication-related osteonecrosis of the jaw. Hopeless teeth should be extracted without drug holiday before the development of inflammation in cancer patients receiving high-dose bone-modifying agents. INTRODUCTION: No studies have comprehensively analyzed the influence of pre-existing inflammation, surgical procedure-related factors such as primary wound closure, demographic factors, and drug holiday on the incidence of medication-related osteonecrosis of the jaw (MRONJ). The purpose of this study was to retrospectively investigate the relationships between these various factors and the development of MRONJ after tooth extraction in cancer patients receiving high-dose bone-modifying agents (BMAs) such as bisphosphonates or denosumab. METHODS: Risk factors for MRONJ after tooth extraction were evaluated with univariate and multivariate analyses. The following parameters were investigated in all patients: demographics, type and duration of BMA use, whether BMA use was discontinued before tooth extraction (drug holiday), the duration of such discontinuation, the presence of pre-existing inflammation, and whether additional surgical procedures (e.g., incision, removal of bone edges, root amputation) were performed. RESULTS: We found that root amputation (OR = 22.62), immunosuppressive therapy (OR = 16.61), extraction of mandibular teeth (OR = 12.14), extraction of teeth with pre-existing inflammation, and longer duration (≥ 8 months) of high-dose BMA (OR = 7.85) were all significantly associated with MRONJ. CONCLUSIONS: Tooth extraction should not necessarily be postponed in cancer patients receiving high-dose BMA. The effectiveness of a short-term drug holiday was not confirmed, as drug holidays had no significant impact on MRONJ incidence. Tooth extraction may be acceptable during high-dose BMA therapy until 8 months after initiation.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Neoplasias/tratamento farmacológico , Extração Dentária/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Conservadores da Densidade Óssea/efeitos adversos , Denosumab/efeitos adversos , Difosfonatos/efeitos adversos , Feminino , Humanos , Imunossupressores/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Raiz Dentária/cirurgia
10.
Osteoporos Int ; 30(9): 1733-1743, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31175404

RESUMO

Given the widespread practice of recommending drug holidays, we reviewed the impact of medication discontinuation of two common anti-osteoporosis therapies (bisphosphonates and denosumab). Trial evidence suggests the risk of new clinical fractures, and vertebral fracture increases when osteoporosis treatment with bisphosphonates or denosumab is stopped. INTRODUCTION: The aim of this paper was to review the available literature to assess what evidence exists to inform clinical decision-making with regard to drug holidays following treatment with bisphosphonates (BiP) or denosumab. METHODS: Systematic review. RESULTS: Differing pharmacokinetics lead to varying outcomes on stopping therapy. Prospective and retrospective analyses report that the risk of new clinical fractures was 20-40% higher in subjects who stopped BiP treatment, and vertebral fracture risk was approximately doubled. Rapid bone loss has been well described following denosumab discontinuation with an incidence of multiple vertebral fractures around 5%. Studies have not identified risk factors for fracture after stopping treatment other than those that provide an indication for treatment (e.g. prior fracture and low BMD). Studies that considered long-term continuation did not identify increased fracture risk, and reported only very low rates of adverse skeletal events such as atypical femoral fracture. CONCLUSIONS: The view that patients on long-term treatment with bisphosphonates or denosumab should always be offered a drug holiday is not supported by the existing evidence. Different pharmacokinetic properties for different therapies require different strategies to manage drug intermission. In contrast, long-term treatment with anti-resorptives is not associated with increased risk of fragility fractures and skeletal adverse events remain rare.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Osteoporose Pós-Menopausa/tratamento farmacológico , Fraturas por Osteoporose/prevenção & controle , Fatores Etários , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/epidemiologia , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Densidade Óssea/fisiologia , Conservadores da Densidade Óssea/uso terapêutico , Tomada de Decisão Clínica/métodos , Denosumab/administração & dosagem , Denosumab/uso terapêutico , Difosfonatos/administração & dosagem , Difosfonatos/uso terapêutico , Esquema de Medicação , Humanos , Osteoporose Pós-Menopausa/fisiopatologia , Fraturas por Osteoporose/epidemiologia , Medição de Risco/métodos , Fatores de Risco , Suspensão de Tratamento
11.
Osteoporos Int ; 30(4): 705-720, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30623214

RESUMO

We performed a systematic review on the effect of drug holidays (discontinuation) on bone mineral density (BMD) and fracture risk. Bisphosphonate discontinuation may be considered for women who do not have low hip BMD after 3-5 years of initial treatment, while women who have low hip BMD may benefit from treatment continuation. INTRODUCTION: We performed a systematic review and meta-analysis on the effect of drug holidays (discontinuation) on BMD and fracture risk. METHODS: We searched PubMed, Embase, and Cochrane Library databases to locate controlled clinical trials and cohort studies evaluating the effect of drug holidays/discontinuation versus osteoporosis treatment continuation. We performed random-effects meta-analyses of hazard ratios of hip and any clinical osteoporotic fracture for individuals who discontinued bisphosphonates compared to persistent users. RESULTS: Thirteen records reporting results from eight different studies met inclusion criteria. The FLEX study found a reduced clinical vertebral fracture risk with 10 years of alendronate therapy compared to 5 (RR 0.45, 95% CI 0.24-0.85), and the HORIZON extension studies found a reduced risk of morphometric vertebral fracture with 6 years of zoledronic acid therapy compared to 3 (OR = 0.51, 95% CI 0.26-0.95); subgroup analyses showed that women with low hip BMD T-scores after the initial treatment period benefitted from continued treatment in terms of reduced vertebral fracture risk. Meta-analysis of adjusted hazard ratios of hip and any clinical osteoporotic fracture for women who discontinued bisphosphonates revealed no significant differences in the risk of hip fracture (summary estimate of HR 1.09, 95% CI 0.87-1.37) or any clinical fracture (summary estimate of HR 1.13, 95% CI 0.75-1.70) compared to persistent users. CONCLUSIONS: Bisphosphonate discontinuation may be considered for women who do not have low hip BMD after 3 to 5 years of initial treatment, while women who have low hip BMD may benefit from treatment continuation.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Difosfonatos/administração & dosagem , Osteoporose Pós-Menopausa/tratamento farmacológico , Fraturas por Osteoporose/prevenção & controle , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/farmacologia , Conservadores da Densidade Óssea/uso terapêutico , Tomada de Decisão Clínica/métodos , Difosfonatos/farmacologia , Difosfonatos/uso terapêutico , Esquema de Medicação , Humanos , Osteoporose Pós-Menopausa/fisiopatologia , Fraturas por Osteoporose/fisiopatologia , Medição de Risco/métodos , Suspensão de Tratamento
12.
BMC Cancer ; 19(1): 1045, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31690262

RESUMO

BACKGROUND: Resistance to chemotherapy is one of the major hurdles in current cancer therapy. With the increasing occurrence of drug resistance, a paradigm shift in treatment strategy is required. Recently "medication vacation" has emerged as a unique, yet uncomplicated strategy in which withdrawal of drug pressure for certain duration allowed tumor cells to regain sensitivity to the drug. However, little is known about the molecular alterations associated with such an outcome. METHODS: In this study, human osteosarcoma (OS) cells resistant to the extensively used drug cisplatin, were withdrawn from drug pressure, and thereafter cytotoxic response of the cells to the drug was evaluated. We further performed next-generation RNA sequencing and compared transcriptome between parental (OS), resistant (OS-R) and the drug withdrawn (OS-DW) cells. Differentially expressed transcripts were identified, and biological association network (BAN), gene ontology (GO) and pathway enrichment analysis of the differentially regulated transcripts were performed to identify key events associated with withdrawal of drug pressure. RESULTS: Following drug withdrawal, the sensitivity of the cells to the drug was found to be regained. Analysis of the expression profile showed that key genes like, IRAK3, IL6ST, RELA, AKT1, FKBP1A and ADIPOQ went significantly down in OS-DW cells when compared to OS-R. Also, genes involved in Wnt signaling, PI3K-Akt, Notch signaling, and ABC transporters were drastically down-regulated in OS-DW cells compared to OS-R. Although, a very small subset of genes maintained similar expression pattern between OS, OS-R and OS-DW, nonetheless majority of the transcriptomic pattern of OS-DW was distinctively different and unique in comparison to either the drug sensitive OS or drug resistant OS-R cells. CONCLUSION: Our data suggests that though drug withdrawal causes reversal of sensitivity, the transcriptomic pattern does not necessarily show significant match with resistant or parental control cells. We strongly believe that exploration of the molecular basis of drug holiday might facilitate additional potential alternative treatment options for aggressive and resistant cancers.


Assuntos
Antineoplásicos/uso terapêutico , Cisplatino/uso terapêutico , Osteossarcoma/tratamento farmacológico , Linhagem Celular Tumoral , Receptor gp130 de Citocina/genética , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos/genética , Perfilação da Expressão Gênica , Ontologia Genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Quinases Associadas a Receptores de Interleucina-1/genética , Análise de Sequência de RNA , Fator de Transcrição RelA/genética , Suspensão de Tratamento
13.
J Theor Biol ; 474: 63-77, 2019 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-30980871

RESUMO

Psoriasis is a chronic skin condition that produces plaques of condensed, scaling skin due to excessively rapid proliferation of keratinocytes. During the disease progression, keratinocyte proliferation is influenced by many immune cells and cytokines. This article deals with a five dimensional deterministic model, which has been derived using quasi-steady-state approximation for describing the dynamics of psoriasis in various cytokines environment. Equilibrium analysis of the system shows that either the system converges to a stable steady state or exhibits a periodic oscillation depending upon system parameters. Finally, introducing a one dimensional impulsive system, we have determined the perfect dose and perfect dosing interval for biologic (TNF-α inhibitor) therapy to control the hyper-proliferation of keratinocytes. We have studied the effect of TNF-α inhibitor by considering both perfect and imperfect dosing during the inductive phase. The maximum possible number of drug holidays and the minimal number of doses that must subsequently be taken while avoiding drug resistance have been calculated for imperfect dosing. Since, psoriasis is non-curable but treatable disease, so the aim is to investigate the minimum dose with highest efficacy and proper dosing interval of TNF-α inhibitor for a psoriatic patient. Through numerical simulations, we have given a detailed prediction about the maximum drug holidays, tolerable for a patient, without loss of previous drug effects. Our theoretical predictions and numerical outcomes may be useful in guiding the design of future clinical trials.


Assuntos
Citocinas/imunologia , Queratinócitos , Modelos Imunológicos , Psoríase , Fator de Necrose Tumoral alfa , Animais , Humanos , Queratinócitos/imunologia , Queratinócitos/patologia , Psoríase/tratamento farmacológico , Psoríase/imunologia , Psoríase/patologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/imunologia
14.
Osteoporos Int ; 29(10): 2315-2321, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29967931

RESUMO

Tooth extraction in patients receiving bisphosphonates is thought to be a risk factor for osteonecrosis of the jaw (ONJ); however, ONJ did not develop, even when tooth extraction was performed with continued oral bisphosphonate therapy. A drug holiday from bisphosphonates before tooth extraction may not be necessary. INTRODUCTION: It is controversial whether bisphosphonate withdrawal is necessary prior to invasive procedures such as tooth extraction in order to prevent bisphosphonate-related osteonecrosis of the jaw (BRONJ). This study aimed to evaluate the clinical safety of continuing oral bisphosphonate therapy in patients undergoing tooth extraction. METHODS: We prospectively enrolled 132 patients (20 men, 112 women) who were receiving oral bisphosphonates for the prevention or treatment of osteoporosis and required tooth extraction. All patients were managed using an identical protocol, which included preoperative antibiotic prophylaxis and did not necessarily require complete wound closure. The patients were classified into groups according to the duration of bisphosphonate administration: < 2 years (n = 51), 2-5 years (n = 41), 5-10 years (n = 28), and > 10 years (n = 12). The groups were compared regarding the time taken for the extraction socket to heal, and the occurrence of BRONJ. Follow-up duration was at least 3 months. RESULTS: A total of 274 teeth were removed. Long-term oral bisphosphonate therapy for > 5 years significantly delayed the healing of the extraction socket in comparison with administration for < 5 years; however, BRONJ did not develop in any group. There was no prolongation of wound healing due to systemic risk factors such as glucocorticoid administration and diabetes mellitus. There were no adverse skeletal events such as bone fracture. CONCLUSIONS: Patients who underwent tooth extraction with continued oral bisphosphonate therapy showed delayed healing of the extraction socket as the cumulative administration period prolonged, but BRONJ did not develop.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Difosfonatos/farmacologia , Extração Dentária/efeitos adversos , Cicatrização/efeitos dos fármacos , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/prevenção & controle , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/uso terapêutico , Difosfonatos/administração & dosagem , Difosfonatos/uso terapêutico , Esquema de Medicação , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
15.
J Neural Transm (Vienna) ; 125(12): 1877-1883, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30182260

RESUMO

We present a family with two members affected by hyperekplexia and two unaffected members. All exons in the glycine receptor alpha 1 subunit gene (GLRA1) were sequenced in all four family members. Our index patient harbored a novel nonsense mutation (p.Trp314*; rs867618642) in the transmembrane domain three of the GLRA1 and a novel missense variant in the NH2-terminal part (p.Val67Met; rs142888296). After development of tolerance for the effective treatment with clobazam a drug holiday led to a sustained restoration of the treatment response.


Assuntos
Códon sem Sentido , Hiperecplexia/genética , Receptores de Glicina/genética , Reflexo de Sobressalto/genética , Feminino , Humanos , Linhagem , Fenótipo , Adulto Jovem
16.
Clin Oral Investig ; 22(2): 597-615, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29332231

RESUMO

OBJECTIVE: The most debated topic about medication-related osteonecrosis of the jaws (MRONJ) is its therapy, as there are no definitive guidelines. The aims of this systematic review were (a) to outline the best therapeutic approach according to the stage at diagnosis and (b) to perform a meta-analysis to assess whether the drug-holiday protocol may be or not an effective method in the management of MRONJ patients. MATERIALS AND METHODS: The systematic review was performed following the PRISMA principles. Results were screened according to inclusion and exclusion criteria regarding staging before/after treatment, follow-up, and information provided by the authors. For statistical analysis, linear variables are reported as means and standard deviations, medians, and inter-quartile range (IQR); normality of data, according to the distribution of complete healing (primary outcome variable), was assessed with the Kolmogorov-Smirnov test. A p value < 0.05 was considered statistically significant for all tests. RESULTS: Thirteen studies were selected out of 1480. None of them was case-controlled or randomized. Conservative approach showed good results at early stages, but heterogeneous result at advanced stages (100% stage 0, stage I range 81-97%, stage II range 63.6-100%, stage III 73%). Surgical approach showed heterogeneous results at all stages (stage I range 0-100%, stage II range 52-100%, stage III range 50-100%). Statistical analysis showed a significantly higher prevalence of completely healed sites in patients who followed the drug-holiday protocol. CONCLUSIONS: The results suggest that the current stage-specific approach for MRONJ therapy is based on a sound clinical rationale. Conservative treatment appears to yield better outcomes at early stages, while further investigations are needed to elucidate the best protocols for the management of advanced stages. The drug-holiday protocol statistically promotes complete healing after oral surgery procedures but the application should be dictated by the condition of each patient. CLINICAL RELEVANCE: At present, early MRONJ stages should be primarily treated by means of a conservative approach while more advanced stages must be carefully evaluated. Individual decisions should be made for every single case even with respect to the drug-holiday protocol.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/prevenção & controle , Conservadores da Densidade Óssea/administração & dosagem , Difosfonatos/administração & dosagem , Suspensão de Tratamento , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Conservadores da Densidade Óssea/efeitos adversos , Difosfonatos/efeitos adversos , Humanos , Revisões Sistemáticas como Assunto
17.
Osteoporos Int ; 28(12): 3431-3438, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28875236

RESUMO

A cohort of 183 postmenopausal women, who had either discontinued or continued bisphosphonates (BPs) after first-line therapy, was used to investigate the relationships between "drug holiday" and clinical fracture. The risk of new clinical fractures was found to be 40% higher in women who had taken a BP "drug holiday." INTRODUCTION: BPs are the most widely used treatment for postmenopausal osteoporosis. The optimal treatment duration, however, remains unclear. The purpose of this study was to evaluate the fracture risk in postmenopausal women with osteoporosis after discontinuing BP treatment (BP "drug holiday"). METHODS: A retrospective analysis was performed at Lille University Hospital (LUH) on postmenopausal women with osteoporosis who had taken a "drug holiday" or continued treatment after first-line BP therapy (3 to 5 years). The occurrence of new clinical fractures during follow-up was also explored. Cox proportional hazards models were used to investigate the relationships between BP "drug holiday" and the occurrence of clinical fractures, while controlling for confounding factors. Survival without new clinical fractures was analyzed using Kaplan-Meier curves and log-rank tests. RESULTS: One hundred eighty-three women (mean age: 61.8 years; SD: 8.7) who had previously undergone BP treatment for 3 to 5 years were enrolled in our study. The patients had received alendronate (n = 81), risedronate (n = 73), zoledronic acid (n = 20), and ibandronate (n = 9). In 166 patients ("drug holiday" group: n = 31; continuous-treatment group: n = 135), follow-up ranged from 6 to 36 months (mean duration: 31.8 months; SD: 8.2). The incidences of new clinical fractures during follow-up were 16.1% (5/31) and 11.9% (16/135). After full adjustment, the hazard ratio of new clinical fractures among "drug holiday" patients was 1.40 (95% CI: 1.12-1.60; p = 0.0095). CONCLUSIONS: After first-line BP therapy in postmenopausal women with osteoporosis, the risk of new clinical fractures was 40% higher in subjects who took a bisphosphonate drug holiday.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Difosfonatos/administração & dosagem , Osteoporose Pós-Menopausa/tratamento farmacológico , Fraturas por Osteoporose/prevenção & controle , Idoso , Conservadores da Densidade Óssea/uso terapêutico , Difosfonatos/uso terapêutico , Esquema de Medicação , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/complicações , Fraturas por Osteoporose/etiologia , Estudos Retrospectivos , Medição de Risco/métodos , Fatores de Risco , Suspensão de Tratamento
18.
Osteoporos Int ; 28(8): 2495-2503, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28540506

RESUMO

The Effectiveness of Discontinuing Bisphosphonates (EDGE) study is a planned pragmatic clinical trial to guide "drug holiday" clinical decision making. This pilot study assessed work flow and feasibility of such a study. While participant recruitment and treatment adherence were suboptimal, administrative procedures were generally feasible and minimally disrupted clinic flow. INTRODUCTION: The comparative effectiveness of continuing or discontinuing long-term alendronate (ALN) on fractures is unknown. A large pragmatic ALN discontinuation study has potential to answer this question. METHODS: We conducted a 6-month pilot study of the planned the EDGE study among current long-term ALN users (women aged ≥65 with ≥3 years of ALN use) to determine study work flow and feasibility including evaluating the administrative aspects of trial conduct (e.g., time to contract, institutional review board (IRB) approval), assessing rates of site and participant recruitment, and evaluating post-randomization outcomes, including adherence, bisphosphonate-associated adverse events, and participant and site satisfaction. We assessed outcomes 1 and 6 months after randomization. RESULTS: Nine sites participated, including seven community-based medical practices and two academic medical centers. On average (SD), contract execution took 3.4 (2.3) months and IRB approval took 13.9 (4.1) days. Sites recruited 27 participants (13 to continue ALN and 14 to discontinue ALN). Over follow-up, 22% of participants did not adhere to their randomization assignment: 30.8% in the continuation arm and 14.3% in the discontinuation arm. No fractures or adverse events were reported. Sites reported no issues regarding work flow, and participants were highly satisfied with the study. CONCLUSIONS: Administrative procedures of the EDGE study were generally feasible, with minimal disruption to clinic flow. In this convenience sample, participant recruitment was suboptimal across most practice sites. Accounting for low treatment arm adherence, a comprehensive recruitment approach will be needed to effectively achieve the scientific goals of the EDGE study.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Difosfonatos/administração & dosagem , Osteoporose Pós-Menopausa/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Tomada de Decisão Clínica , Esquema de Medicação , Estudos de Viabilidade , Feminino , Humanos , Adesão à Medicação/estatística & dados numéricos , Fraturas por Osteoporose/prevenção & controle , Projetos Piloto , Suspensão de Tratamento
19.
Epilepsia ; 58(6): 1054-1062, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28401980

RESUMO

OBJECTIVE: Nonadherence to prescribed dosing regimens is a significant problem in the treatment of pediatric and adult chronic epilepsy, and can result in severe consequences to patient outcomes. In this first-of-kind preclinical study, the impact of nonadherence on seizure control was studied by simulating human patterns of nonadherence in an animal epilepsy model. METHODS: In study 1, three different patterns of nonadherence were modeled in newly diagnosed epileptic rats treated with carbamazepine: perfect adherence (100% of pellets contained carbamazepine), variable nonadherence (50% of pellets contained carbamazepine with different dosing patterns between animals), and complete nonadherence (0% of pellets contained carbamazepine). In study 2, a cohort of newly diagnosed epileptic rats were subjected to a "drug holiday" nonadherence paradigm, that is, a 2-week on (100%), 2-week off (0%), and 2-week on (100%) carbamazepine paradigm. RESULTS: In the first experiment, the 100% (0.3 ± 0.2 SD convulsive seizures per day) adherent cohort demonstrated better seizure control than either the 0% (1.1 ± 0.8 SD) or 50% (0.8 ± 0.6 SD) adherent cohorts, which had similar levels of seizure control. In the second study, poor seizure control was exhibited during the second 2 weeks; that is, the drug holiday epoch; however, this did not negatively affect restoration of seizure control upon reinstatement of CBZ. SIGNIFICANCE: The results from this pilot investigation suggest that nonadherence to carbamazepine is associated with significant negative but reversible effects on seizure control in an animal model of epilepsy. Furthermore, these results demonstrate that animal studies of nonadherence can yield potentially important and translatable insights into the consequences of nonadherence on seizure control.


Assuntos
Anticonvulsivantes/efeitos adversos , Anticonvulsivantes/uso terapêutico , Carbamazepina/efeitos adversos , Carbamazepina/uso terapêutico , Modelos Animais de Doenças , Epilepsia/tratamento farmacológico , Adesão à Medicação , Animais , Estudos Cross-Over , Relação Dose-Resposta a Droga , Esquema de Medicação , Eletroencefalografia/efeitos dos fármacos , Epilepsia/induzido quimicamente , Humanos , Ácido Caínico , Masculino , Ratos , Ratos Sprague-Dawley
20.
Osteoporos Int ; 27(5): 1701-8, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26642963

RESUMO

UNLABELLED: In a retrospective analysis of 208 osteoporotic patients followed during a bisphosphonate holiday, lower body weight and risedronate use were associated with a more rapid decline in bone mineral density during the bisphosphonate holiday, while bone mineral density (BMD) trends were similar in patients who sustained vs. did not sustain a fracture. INTRODUCTION: A drug holiday has been suggested for some bisphosphonate-treated patients with osteoporosis to minimize potential side effects from prolonged use. However, there is limited information on the evolution of BMD during a bisphosphonate holiday. Our study analyzed the longitudinal course of BMD following bisphosphonate discontinuation and assessed its determinants. METHODS: Retrospective single-center cohort study of osteoporosis patients treated with alendronate or risedronate for at least 2 years and then discontinued their bisphosphonate for a drug holiday. Patients were stratified by bisphosphonate type and by fracture occurrence during drug holiday. RESULTS: A total of 208 patients were included in this analysis (87.5 % female). At the time of bisphosphonate cessation, mean ± SD age was 66.9 ± 8.9 years and BMI 24.5 ± 4.4 kg/m(2). Duration of bisphosphonate treatment was 5.2 ± 2.3 years, and follow-up during holiday was 3.3 ± 1.7 years. During the first 2 years of the holiday, BMD remained stable at the lumbar spine and femoral neck, but declined significantly at the total hip. BMD declined significantly at all sites thereafter. Significant predictors of BMD decline during bisphosphonate holiday included lower BMI at the start of the holiday and change in body weight during the holiday. BMD decline was more pronounced in former risedronate compared to former alendronate users. BMD trends were similar in patients who sustained vs. did not sustain a fracture during the holiday. CONCLUSIONS: BMD at the total hip declines significantly within 1 year of bisphosphonate discontinuation, particularly in lean patients. Additional studies are needed to identify predictors of fracture incidence during a bisphosphonate holiday.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Densidade Óssea/efeitos dos fármacos , Difosfonatos/administração & dosagem , Osteoporose/tratamento farmacológico , Fraturas por Osteoporose/etiologia , Idoso , Alendronato/administração & dosagem , Alendronato/farmacologia , Alendronato/uso terapêutico , Peso Corporal/fisiologia , Conservadores da Densidade Óssea/farmacologia , Conservadores da Densidade Óssea/uso terapêutico , Difosfonatos/farmacologia , Difosfonatos/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/complicações , Osteoporose/fisiopatologia , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/tratamento farmacológico , Osteoporose Pós-Menopausa/fisiopatologia , Fraturas por Osteoporose/fisiopatologia , Fraturas por Osteoporose/prevenção & controle , Estudos Retrospectivos , Ácido Risedrônico/administração & dosagem , Ácido Risedrônico/farmacologia , Ácido Risedrônico/uso terapêutico , Medição de Risco , Suspensão de Tratamento
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