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1.
Braz J Phys Ther ; 27(3): 100514, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37224618

RESUMEN

BACKGROUND: Shoulder injuries are associated with proprioceptive deficits. Elastic kinesiology tape (KT) is used for treating musculoskeletal disorders, including shoulder injuries, as it arguably improves proprioception. OBJECTIVE: To synthesize the evidence on the effects of elastic KT on proprioception in healthy and pathological shoulders. METHODS: Four databases (PubMed, WoS, CINAHL, SPORTDiscus) were searched for studies that investigated the effects of elastic KT on shoulder proprioception. Outcome measures were active joint position sense (AJPS), passive joint position sense (PJPS), kinesthesia, sense of force (SoF), and sense of velocity (SoV). Risk of bias (RoB) was assessed using the Cochrane Collaboration RoB tool for randomized controlled trials (RCTs), and the ROBINS-1 for non-RCTs, while the certainty of evidence was determined using GRADE. RESULTS: Eight studies (5 RCTs, 3 non-RCTs) were included, yielding 187 shoulders (102 healthy and 85 pathological shoulders). RoB ranged from low (2 studies), moderate (5 studies), to high (1 study). Elastic KT has a mixed effect on AJPS of healthy shoulders (n=79) (low certainty). Elastic KT improves AJPS (subacromial pain syndrome and rotator cuff tendinopathy, n=52) and PJPS (chronic hemiparetic shoulders, n=13) among pathological shoulders (very low certainty). Elastic KT has no effect on kinesthesia among individuals with subacromial pain syndrome (n=30) (very low certainty). CONCLUSION: There is very low to low certainty of evidence that elastic KT enhances shoulder AJPS and PJPS. The aggregate of evidence is currently so low that any recommendation on the effectiveness of elastic KT on shoulder proprioception remains speculative.


Asunto(s)
Cinta Atlética , Enfermedades Musculoesqueléticas , Lesiones del Hombro , Humanos , Hombro , Rango del Movimiento Articular , Propiocepción , Dolor
2.
J Dairy Sci ; 105(2): 1638-1648, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34802728

RESUMEN

The objective of this observational cross-sectional study was to describe the cleanliness of various equipment used for colostrum harvest and calf feeding procedures on dairy farms in Québec, Canada. The study was performed on 42 commercial dairy herds also enrolled in another study aiming to determine the transfer of passive immunity over a 14-mo period. Information on colostrum quality (using Brix value) and cleanliness (total aerobic and total coliform count) were recorded as well as various practices focused on colostrum-feeding equipment and preweaning period using a standard questionnaire. During the study period, colostrum and milk-feeding equipment cleanliness was assessed using direct surface swabbing with Hygiena Ultrasnap swabs. A total of 155 swab samples were obtained from 6 pieces of equipment. Adenosine triphosphate collected from the swabbed surface reacts with the luciferase solution present in the swab by bioluminescence, which is proportional to the quantity of ATP present and quantified as relative light units (RLU). The description of feed equipment cleanliness (defined as the maximal RLU found for a specific herd, dichotomized as <1,000 RLU vs. ≥1,000 RLU) was compared with the herds' descriptive characteristics, focusing on the first 2 components of a multiple correspondence analysis. The median (range) RLU for buckets used for colostrum harvest, bucket or bottle used for feeding, tube feeders, milking colostrum line, and internal surface of the nipples were 41 RLU (3-1,625 RLU), 78 RLU (<1-3,765 RLU), 29 RLU (<1-2,177 RLU), 83 RLU (<1-9,968 RLU), and 1,101 RLU (2-9,546 RLU), respectively. The first 2 components of multiple correspondence analysis explained 24.7% of data variances and were related to the farms' hygiene and health (13.0%) and feeding practices (11.7% of data variance). The maximal dichotomized luminometry value (<1,000 RLU or ≥1,000 RLU) was associated with hygiene and health dimension. This study gave promising results concerning the potential application of ATP luminometry for calf rearing practices assessment.


Asunto(s)
Calostro , Industria Lechera , Adenosina Trifosfato , Animales , Granjas , Femenino , Leche , Embarazo
3.
J Foot Ankle Res ; 13(1): 69, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33261633

RESUMEN

STUDY DESIGN: Single-blind parallel group randomized clinical trial. OBJECTIVES: To compare the effects of neurocryostimulation (NCS) with those of traditional ice application on functional recovery, pain, edema and ankle dorsiflexion range of motion (ROM) in individuals receiving physiotherapy treatments for acute lateral ankle sprains (LAS). BACKGROUND: Ankle sprain is a very common injury and its management is often costly, with important short- and long-term impacts on individuals and society. As new methods of therapy using cold (cryotherapy) are emerging for the treatment of musculoskeletal conditions, little evidence exists to support their use. NCS, which provokes a rapid cooling of the skin with the liberation of pressured CO2, is a method believed to accelerate the resorption of edema and recovery in the case of traumatic injuries. METHODS: Forty-one participants with acute LAS were randomly assigned either to a group that received in-clinic physiotherapy treatments and NCS (experimental NCS group, n = 20), or to a group that received the same in-clinic physiotherapy treatments and traditional ice application (comparison ice group, n = 21). Primary (Lower Extremity Functional Scale - LEFS) and secondary (visual analog scale for pain intensity at rest and during usual activities in the last 48 h, Figure of Eight measurement of edema, and weight bearing lunge for ankle dorsiflexion range of motion) outcomes were evaluated at baseline (T0), after one week (T1), two weeks (T2), four weeks (T4) and finally, after six weeks (T6). The effects of interventions were assessed using two-way ANOVA-type Nonparametric Analysis for Longitudinal Data (nparLD). RESULTS: No significant group-time interaction or group effect was observed for all outcomes (0.995 ≥ p ≥ 0.057) following the intervention. Large time effects were however observed for all outcomes (p <  0.0001). CONCLUSION: Results suggest that neurocryostimulation is no more effective than traditional ice application in improving functional recovery, pain, edema, and ankle dorsiflexion ROM during the first six weeks of physiotherapy treatments in individuals with acute LAS. LEVEL OF EVIDENCE: Therapy, level 1b. TRIAL REGISTRATION: ClinicalTrials.gov , NCT02945618 . Registered 23 October 2016 - Retrospectively registered (25 participants recruited prior to registration, 17 participants after).


Asunto(s)
Traumatismos del Tobillo/terapia , Artralgia/terapia , Crioterapia/métodos , Terapia por Estimulación Eléctrica/métodos , Hielo , Adulto , Traumatismos del Tobillo/complicaciones , Traumatismos del Tobillo/fisiopatología , Articulación del Tobillo/inervación , Articulación del Tobillo/fisiopatología , Artralgia/etiología , Artralgia/fisiopatología , Femenino , Humanos , Masculino , Dimensión del Dolor , Rango del Movimiento Articular , Recuperación de la Función , Método Simple Ciego , Resultado del Tratamiento , Soporte de Peso
4.
J Food Drug Anal ; 27(3): 679-691, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31324284

RESUMEN

The targeted analysis of veterinary drug residues in honey traditionally involves a series of extraction and purification steps prior to quantification with high performance liquid chromatography coupled to high resolution or tandem mass spectrometry. These steps, designed to separate the target analytes from interferences, are generally time-consuming and costly. In addition, traditional cleanup steps are likely to eliminate other compounds whose analysis could prove decisive in current or future assessment of the honey sample. Alternatively, direct injection without complex sample preparation steps has been introduced for the fast analysis of trace compounds in environmental and food matrices. The aim of this study was to develop a rapid method for the targeted analysis of 7 key veterinary drug residues in honey based on direct injection high performance liquid chromatography coupled to quadrupole time-of-flight, while simultaneously recording data-independent MS/MS (e.g. All Ions MS/MS data) for future re-examination of the data for other purposes. The new method allowed for the detection of the target residues at levels approximately 20-100 times lower than current regulatory limits, for a total analysis time of about 45 min. The recoveries (103-119%), the linearity (R ≥ 0.996) and the repeatability (RSD ≤ 7%) were satisfactory. The method was then applied to 35 honey samples from the Canadian market. Residues of tylosin A, tylosin B, sulfamethazine and sulfadimethoxine were detected in 6, 9, 6 and 23% of the samples respectively, at levels below the regulatory limits in Canada. The possibility of adding a hydrolysis step to study sulfonamides in honey was tested, which provided good results for this family of compounds but lead to degradation of some of the other analytes. Finally, the non-targeted identification of several compounds was demonstrated as a proof of concept of future re-examination of All Ions MS/MS data. This paper illustrates the capacity of this novel method to combine targeted and non-targeted screening of chemical residues in honey.


Asunto(s)
Antibacterianos/análisis , Miel/análisis , Cromatografía Líquida de Alta Presión , Evaluación Preclínica de Medicamentos , Espectrometría de Masas
5.
Vet Res ; 48(1): 56, 2017 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-28934980

RESUMEN

Staphylococcus aureus intramammary infections (IMIs) have low cure rates using standard antibiotic treatment and increasing the duration of treatment usually improves therapeutic success. Chronic IMIs are thought to be caused by bacteria presenting a specific virulence phenotype that includes the capacity to produce greater amounts of biofilm. In this study, antibiotic susceptibility and biofilm production by S. aureus isolates recovered from IMIs that were cured or not following an extended therapy with cephapirin, pirlimycin or ceftiofur for 5, 8 and 8 days, respectively, were compared. An isolate was confirmed as from a persistent case (not cured) if the same S. aureus strain was isolated before and after treatment as revealed by the same VNTR profile (variable number of tandem repeats detected by multiplex PCR). The antibiotic minimal inhibitory concentrations (MICs) were determined for these isolates as well as the capacity of the isolates to produce biofilm. Isolates from persistent cases after extended therapy with cephapirin or ceftiofur had higher MICs for these drugs compared to isolates from non-persistent cases (p < 0.05) even though the antibiotic susceptibility breakpoints were not exceeded. Isolates of the ceftiofur study significantly increased their biofilm production in presence of a sub-MIC of ceftiofur (p < 0.05), whereas isolates from the pirlimycin group produced significantly less biofilm in presence of a sub-MIC of pirlimycin (p < 0.001). Relative antibiotic susceptibility of the isolates as well as biofilm production may play a role in the failure of extended therapies. On the other hand, some antibiotics may counteract biofilm formation and improve cure rates.


Asunto(s)
Antibacterianos/uso terapéutico , Biopelículas/efectos de los fármacos , Enfermedades de la Mama/veterinaria , Enfermedades de los Bovinos/microbiología , Cefalosporinas/uso terapéutico , Cefapirina/uso terapéutico , Clindamicina/análogos & derivados , Infecciones Estafilocócicas/veterinaria , Staphylococcus aureus/efectos de los fármacos , Animales , Enfermedades de la Mama/tratamiento farmacológico , Enfermedades de la Mama/microbiología , Bovinos , Enfermedades de los Bovinos/tratamiento farmacológico , Clindamicina/uso terapéutico , Farmacorresistencia Bacteriana/genética , Femenino , Pruebas de Sensibilidad Microbiana/veterinaria , Repeticiones de Minisatélite/genética , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/genética
6.
Man Ther ; 20(5): 703-8, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25907145

RESUMEN

BACKGROUND: Multiple factors have been associated with the presence of a subacromial pain syndrome (SPS), including deficits in performance of scapular and glenohumeral muscles. Such deficits can lead to inadequate kinematics and decreased acromiohumeral distance (AHD). Exercises that aim at correcting these deficits, such as movement training, were suggested to improve symptoms and functional limitations. To date, few studies have assessed outcomes following an intervention focused on movement training. OBJECTIVES: Evaluate the effects of a rehabilitation program based on movement training on symptoms, functional limitations and AHD in individuals with SPS. DESIGN: Prospective single group pre-post design. METHODS: Twenty-five participants with SPS (SPS group) participated in a 6-week program. Twenty asymptomatic volunteers were recruited for normative AHD values (control group). Outcomes of both groups were evaluated at baseline and 6 weeks, i.e. immediately following intervention for the SPS group. Changes in symptoms and functional limitations for SPS group were assessed using the Western Ontario Rotator Cuff (WORC) index and Disability of the Arm Shoulder and Hand (DASH) questionnaire. Changes in AHD for both groups were assessed using ultrasonographic measures. RESULTS: Following the rehabilitation program, the scores on WORC and DASH were significantly improved (p < 0.001). AHD increased significantly in the SPS group (p = 0.019), especially in a subgroup with initial deficits (p < 0.001). CONCLUSION: The rehabilitation program yielded improvements in symptoms and functional limitations in participants with SPS. Moreover, it led to an increase of the AHD--thus potentially decreasing subacromial compression, particularly in participants with an initially smaller AHD. The trial was registered at ClinicalTrials.gov: identifier--NCT02395770.


Asunto(s)
Terapia por Ejercicio/métodos , Manipulaciones Musculoesqueléticas/métodos , Síndrome de Abducción Dolorosa del Hombro/rehabilitación , Dolor de Hombro/rehabilitación , Acromion/anatomía & histología , Adolescente , Adulto , Anciano , Análisis de Varianza , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Húmero/anatomía & histología , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Estudios Prospectivos , Recuperación de la Función , Entrenamiento de Fuerza/métodos , Medición de Riesgo , Síndrome de Abducción Dolorosa del Hombro/diagnóstico , Dolor de Hombro/diagnóstico , Ultrasonografía Doppler , Adulto Joven
7.
J Orthop Sports Phys Ther ; 45(5): 330-50, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25808530

RESUMEN

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVES: To evaluate the efficacy of manual therapy (MT) for patients with rotator cuff (RC) tendinopathy. BACKGROUND: Rotator cuff tendinopathy is a highly prevalent musculoskeletal disorder, for which MT is a common intervention used by physical therapists. However, evidence regarding the efficacy of MT is inconclusive. METHODS: A literature search using terms related to shoulder, RC tendinopathy, and MT was conducted in 4 databases to identify randomized controlled trials that compared MT to any other type of intervention to treat RC tendinopathy. Randomized controlled trials were assessed with the Cochrane risk-of-bias tool. Meta-analyses or qualitative syntheses of evidence were performed. RESULTS: Twenty-one studies were included. The majority had a high risk of bias. Only 5 studies had a score of 69% or greater, indicating a moderate to low risk of bias. A small but statistically significant overall effect for pain reduction of MT compared with a placebo or in addition to another intervention was observed (n = 406), which may or may not be clinically important, given a mean difference of 1.1 (95% confidence interval: 0.6, 1.6) on a 10-cm visual analog scale. Adding MT to an exercise program (n = 226) significantly decreased pain (mean difference, 1.0; 95% confidence interval: 0.7, 1.4), as reported on a 10-cm visual analog scale, which may or may not be clinically important. Based on qualitative analyses, it is unclear whether MT used alone or added to an exercise program improves function. CONCLUSION: For patients with RC tendinopathy, based on low- to moderate-quality evidence, MT may decrease pain; however, it is unclear whether it can improve function. More methodologically sound studies are needed to make definitive conclusions. LEVEL OF EVIDENCE: Therapy, level 1a-.


Asunto(s)
Manipulaciones Musculoesqueléticas , Manguito de los Rotadores , Tendinopatía/terapia , Terapia por Ejercicio , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
8.
J Orthop Sports Phys Ther ; 45(1): 4-17, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25420010

RESUMEN

STUDY DESIGN: Participant- and assessor-blinded randomized clinical trial. OBJECTIVES: To compare a rehabilitation program thought to increase the size of the intervertebral foramen (IVF) of the affected nerve root to a rehabilitation program that doesn't include any specific techniques thought to increase the size of the IVF in patients presenting with cervical radiculopathy (CR). BACKGROUND: Clinical approaches for the treatment of CR commonly include exercises and manual therapy techniques thought to increase the size of the IVF, but evidence regarding the effectiveness of these specific manual therapy techniques is scarce. METHODS: Thirty-six participants with CR were randomly assigned either to a group that received a manual therapy and exercise program aimed at increasing the size of the IVF of the affected nerve root (experimental group, n=18) or to a group that received a manual therapy and exercise program without the specific goal of increasing the size of the IVF of the affected level and side (comparison group, n=18). Primary (Neck Disability Index) and secondary (shortened version of the Disabilities of the Arm, Shoulder and Hand questionnaire [QuickDASH] and numeric pain-rating scale) outcomes were evaluated at baseline, at the end of the 4-week program (week 4), and 4 weeks later (week 8). A mixed-model, 2-way analysis of variance was used to analyze treatment effects. RESULTS: No significant group-by-time interaction or group effect was observed for Neck Disability Index, QuickDASH, and numeric pain-rating scale scores (P≥.14) following the intervention. However, both groups showed statistically and clinically significant improvement from baseline to week 4 and to week 8 in Neck Disability Index, QuickDASH, and numeric pain-rating scale scores (P<.05). CONCLUSION: Results suggest that manual therapy and exercises are effective in reducing pain and functional limitations related to CR. The addition of techniques thought to increase the size of the IVF of the affected nerve root yielded no significant additional benefits. Given the absence of a "no treatment" group, a spontaneous resolution of symptoms cannot be excluded. However, the magnitude of improvement makes spontaneous resolution unlikely. The trial was registered at ClinicalTrials.gov (NCT01500044). LEVEL OF EVIDENCE: Therapy, level 1b-.


Asunto(s)
Terapia por Ejercicio/métodos , Manipulaciones Musculoesqueléticas/métodos , Radiculopatía/terapia , Adolescente , Adulto , Anciano , Vértebras Cervicales/fisiopatología , Evaluación de la Discapacidad , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Radiculopatía/fisiopatología , Encuestas y Cuestionarios , Resultado del Tratamiento , Adulto Joven
9.
Chiropr Osteopat ; 18: 7, 2010 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-20409327

RESUMEN

BACKGROUND: When conservative therapies for low back pain (LBP) are not effective, elective surgery may be proposed to these patients. Over the last 20 years, a new technology, disc replacement, has become increasingly popular because it is believed to maintain or restore the integrity of spinal movement and minimize the side-effects compared to fusion. Although disc replacement may relieve a patient from pain and related disability, soreness and stiffness of the lumbopelvic region seem to be common aftermaths of the surgery. This prospective case series was undertaken to identify and describe potential adverse events of lumbar spinal manipulation, a common therapy for low back pain, in a group of patients with symptoms after disc prostheses. CASES PRESENTATION: Eight patients who underwent lumbar spine total disc replacement were referred by an orthopaedic surgeon for chiropractic treatments. These patients had 1 or 2 total lumbar disc replacements and were considered stable according to the surgical protocol but presented persistent, post-surgical, non-specific LBP or pelvic pain. They were treated with lumbar spine side posture manipulations only and received 8 to 10 chiropractic treatments based on the clinical evolution and the chiropractor's judgment. Outcome measures included benign, self-limiting, and serious adverse events after low back spinal manipulative therapy. The Oswestry Disability Index, a pain scale and the fear avoidance belief questionnaire were administered to respectively assess disability, pain and fear avoidance belief about work and physical activity. This prospective case series comprised 8 patients who all had at least 1 total disc replacement at the L4/L5 or L5/S1 level and described persistent post-surgical LBP interfering with their daily activities. Commonly-reported side-effects of a benign nature included increased pain and/or stiffness of short duration in nearly half of the chiropractic treatment period. No major or irreversible complication was noted. CONCLUSIONS: During the short treatment period, no major complication was encountered by the patients. Moreover, the benign side-effects reported after lumbar spine manipulation were similar in nature and duration to those frequently experienced by the general population.

10.
J Electromyogr Kinesiol ; 20(5): 939-46, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19900823

RESUMEN

Persons with shoulder impingement syndrome (SIS) present impairments that can be improved following supervised movement training with feedback; however, retention is low. The purpose of this study was to evaluate if kinematic changes observed following supervised training can be maintained using unsupervised training with visual feedback. Thirty-three subjects with SIS participated in two visits, one day apart. Kinematic patterns of the upper limb were evaluated once during the first visit, immediately after supervised training; they were evaluated twice during the second visit, before and immediately after unsupervised training. Kinematic patterns were characterized by total excursion and final position during reaching. Unsupervised training consisted of reaching movements performed in front of a mirror. The day after supervised training, subjects with SIS used significantly larger trunk rotation and finished reaching with the trunk more rotated as compared to immediately after supervised training. Following unsupervised training, kinematics of the trunk was back to the level observed immediately after supervised training. Subjects who presented the largest kinematic deficits also significantly improved their shoulder and clavicular movements. Unsupervised training appears to be a good complement to supervised training in order to normalize the kinematic impairments of persons with SIS as compared to healthy subjects.


Asunto(s)
Brazo/fisiopatología , Biorretroalimentación Psicológica/métodos , Terapia por Ejercicio/métodos , Retroalimentación Sensorial , Autocuidado/métodos , Síndrome de Abducción Dolorosa del Hombro/fisiopatología , Síndrome de Abducción Dolorosa del Hombro/rehabilitación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Rango del Movimiento Articular , Síndrome de Abducción Dolorosa del Hombro/diagnóstico , Resultado del Tratamiento
12.
HPB (Oxford) ; 9(1): 52-7, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18333113

RESUMEN

BACKGROUND: Orthotopic liver transplantation (OLT) may be associated with massive blood loss and the need for allogenic blood product transfusions. Cell salvage autotransfusion (CS) is an attractive alternative to allogenic red blood cell (RBC) transfusion. However, controversy surrounds its usefulness during OLT; some studies stated that CS decreased transfusions of allogenic blood products and others stated that blood loss was increased. The aim of this study was to evaluate the efficiency of the CS during OLT. PATIENTS AND METHODS: After approval by the institutional ethics committee, a prospective survey was undertaken. A total of 150 consecutive OLTs were included in the study. Two groups of patients were formed. Period 1 included patients 1-75 with no CS use. Period 2 comprised patients 76-150 with systematic CS use. RESULTS: Patients from both periods were comparable. CS was used in all cases in period 2, and there was enough salvaged blood to retransfuse 65% of these OLTs. The mean volume of retransfused blood was 338+/-339 ml. The transfusion rate did not change from period 1 to period 2. The mean number of RBC units transfused per patient was 0.4+/-0.9 vs 0.4+/-1.2 with 78.7% vs 81.3% of cases not receiving transfusion of any blood product. The threshold for RBC transfusions was the same. The length of surgery and blood loss were greater in period 2 than in period 1 (associated with the arrival of two junior surgeons), but the hemoglobin (Hb) value was also higher at the end of surgery (93.8+/-19.3 g/L vs 85.2+/-17.8 g/L, p<0.0001). CONCLUSION: Despite increased blood loss in period 2, CS saved 21 g/L of Hb per patient or two RBC unit transfusions. As long as we cannot predict with accuracy which patients will bleed, we will continue to use the CS for all OLTs.

13.
J Clin Oncol ; 23(24): 5805-13, 2005 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-16027437

RESUMEN

PURPOSE: Many cancer patients take antioxidant vitamin supplements with the hope of improving the outcome of conventional therapies and of reducing the adverse effects of these treatments. A randomized trial was conducted to determine whether supplementation with antioxidant vitamins could reduce the occurrence and severity of acute adverse effects of radiation therapy and improve quality of life without compromising treatment efficacy. PATIENTS AND METHODS: We conducted a randomized, double-blind, placebo-controlled trial among 540 head and neck cancer patients treated with radiation therapy. Patients were randomly assigned into two arms. The supplementation with alpha-tocopherol (400 IU/d) and beta-carotene (30 mg/d) or placebos was administered during radiation therapy and for 3 years thereafter. During the course of the trial, supplementation with beta-carotene was discontinued because of ethical concerns. RESULTS: Patients randomly assigned in the supplement arm tended to have less severe acute adverse effects during radiation therapy (odds ratio [OR], 0.72; 95% CI, 0.52 to 1.02). The reduction was statistically significant when the supplementation combined alpha-tocopherol and beta-carotene for adverse effects to the larynx (OR, 0.38; 95% CI, 0.21 to 0.71) and overall at any site (OR, 0.38; 95% CI, 0.20 to 0.74). Quality of life was not improved by the supplementation. The rate of local recurrence of the head and neck tumor tended to be higher in the supplement arm of the trial (hazard ratio, 1.37; 95% CI, 0.93 to 2.02). CONCLUSION: Supplementation with high doses of alpha-tocopherol and beta-carotene during radiation therapy could reduce the severity of treatment adverse effects. However, this trial suggests that use of high doses of antioxidants as adjuvant therapy might compromise radiation treatment efficacy.


Asunto(s)
Antioxidantes/uso terapéutico , Neoplasias de Cabeza y Cuello/radioterapia , Traumatismos por Radiación/prevención & control , alfa-Tocoferol/uso terapéutico , beta Caroteno/uso terapéutico , Enfermedad Aguda , Análisis de Varianza , Distribución de Chi-Cuadrado , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Calidad de Vida , Análisis de Supervivencia
14.
J Natl Cancer Inst ; 97(7): 481-8, 2005 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-15812073

RESUMEN

BACKGROUND: Although low dietary intakes of antioxidant vitamins and minerals have been associated with higher risks of cancer, results of trials testing antioxidant supplementation for cancer chemoprevention have been equivocal. We assessed whether supplementation with antioxidant vitamins could reduce the incidence of second primary cancers among patients with head and neck cancer. METHODS: We conducted a multicenter, double-blind, placebo-controlled, randomized chemoprevention trial among 540 patients with stage I or II head and neck cancer treated by radiation therapy between October 1, 1994, and June 6, 2000. Supplementation with alpha-tocopherol (400 IU/day) and beta-carotene (30 mg/day) or placebo began on the first day of radiation therapy and continued for 3 years after the end of radiation therapy. In the course of the trial, beta-carotene supplementation was discontinued after 156 patients had enrolled because of ethical concerns. The remaining patients received alpha-tocopherol or placebo only. Survival was evaluated by Kaplan-Meier analysis. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). All statistical tests were two-sided. RESULTS: After a median follow-up of 52 months, second primary cancers and recurrences of the first tumor were diagnosed in 113 and 119 participants, respectively. The effect of supplementation on the incidence of second primary cancers varied over time. Compared with patients receiving placebo, patients receiving alpha-tocopherol supplements had a higher rate of second primary cancers during the supplementation period (HR = 2.88, 95% CI = 1.56 to 5.31) but a lower rate after supplementation was discontinued (HR = 0.41, 95% CI = 0.16 to 1.03). Similarly, the rate of having a recurrence or second primary cancer was higher during (HR = 1.86, 95% CI = 1.27 to 2.72) but lower after (HR = 0.71, 95% CI = 0.33 to 1.53) supplementation with alpha-tocopherol. The proportion of participants free of second primary cancer overall after 8 years of follow-up was similar in both arms. CONCLUSIONS: alpha-Tocopherol supplementation produced unexpected adverse effects on the occurrence of second primary cancers and on cancer-free survival.


Asunto(s)
Antioxidantes/administración & dosificación , Antioxidantes/efectos adversos , Neoplasias de Cabeza y Cuello/radioterapia , Neoplasias Inducidas por Radiación/prevención & control , Neoplasias Primarias Secundarias/prevención & control , alfa-Tocoferol/administración & dosificación , alfa-Tocoferol/efectos adversos , beta Caroteno/administración & dosificación , beta Caroteno/efectos adversos , Adulto , Anciano , Anticarcinógenos/administración & dosificación , Anticarcinógenos/efectos adversos , Factores de Confusión Epidemiológicos , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/prevención & control , Neoplasias Inducidas por Radiación/epidemiología , Neoplasias Primarias Secundarias/epidemiología , Neoplasias Primarias Secundarias/etiología , Oportunidad Relativa , Modelos de Riesgos Proporcionales , Radioterapia/efectos adversos , Análisis de Supervivencia , Insuficiencia del Tratamiento
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