994 resultados para Estimadores de Kaplan-Meier
Resumo:
Background: Although numerous studies and metanalysis have shown the beneficial effect of statin therapy in CVD secondary prevention, there is still controversy such the use of statins for primary CVD prevention in patients with DM. The purpose of this study was to evaluate the occurrence of total major adverse cardio-vascular events (MACE) in a cohort of patients with type 2 diabetes complicated by nephropathy treated with statins, in order to verify real life effect of statin on CVD primary prevention. Methods: We conducted an observational prospective multicenter study on 564 patients with type 2 diabetic nephropathy free of cardiovascular disease attending 21 national outpatient diabetes clinics and followed them up for 8 years. 169 of them were treated with statins (group A) while 395 were not on statins (group B). Results: Notably, none of the patients was treated with a high-intensity statin therapy according to last ADA position statement. Total MACE occurred in 32 patients from group A and in 68 patients from group B. Fatal MACE occurred in 13 patients from group A and in 30 from group B; nonfatal MACE occurred in 19 patients from group A and in 38 patients from group B. The analysis of the Kaplan-Meier survival curves showed a not statistically significant difference in the incidence of total (p 0.758), fatal (p 0.474) and nonfatal (p 0.812) MACE between the two groups. HbA1c only showed a significant difference in the incidence of MACE between the two groups (HR 1.201, CI 1.041-1.387, p 0.012). Conclusions: These findings suggest that, in a real clinical setting, moderate-intensity statin treatment is ineffective in cardiovascular primary prevention for patients with diabetic nephropathy.
Resumo:
Background: Oral cancer is a significant public health problem world-wide and exerts high economic, social, psychological, and physical burdens on patients, their families, and on their primary care providers. We set out to describe the changing trends in incidence and survival rates of oral cancer in Ireland between 1994 and 2009. Methods: National data on incident oral cancers [ICD 10 codes C01-C06] were obtained from the National Cancer Registry Ireland from 1994 to 2009. We estimated annual percentage change (APC) in oral cancer incidence during 1994–2009 using joinpoint regression software (version 4.2.0.2). The lifetime risk of oral cancer to age 79 was estimated using Irish incidence and population data from 2007 to 2009. Survival rates were also examined using Kaplan-Meier curves and Cox proportional hazard models to explore the influence of several demographic/lifestyle covariates with follow-up to end 2012. Results: Data were obtained on 2,147 oral cancer incident cases. Men accounted for two-thirds of oral cancer cases (n = 1,430). Annual rates in men decreased significantly during 1994–2001 (APC = -4.8 %, 95 % CI: −8.7 to −0.7) and then increased moderately (APC = 2.3 %, 95 % CI: −0.9 to 5.6). In contrast, annual incidence increased significantly in women throughout the study period (APC = 3.2 %, 95 % CI: 1.9 to 4.6). There was an elevated risk of death among oral cancer patients who were: older than 60 years of age; smokers; unemployed or retired; those living in the most deprived areas; and those whose tumour was sited in the base of the tongue. Being married and diagnosed in more recent years were associated with reduced risk of death. Conclusion: Oral cancer increased significantly in both sexes between 1999 and 2009 in Ireland. Our analyses demonstrate the influence of measured factors such as smoking, time of diagnosis and age on observed trends. Unmeasured factors such as alcohol use, HPV and dietary factors may also be contributing to increased trends. Several of these are modifiable risk factors which are crucial for informing public health policies, and thus more research is needed.
Resumo:
En Colombia se ha podido establecer que la incidencia y mortalidad de la Enfermedad Renal Crónica Terminal continúan en aumento en los últimos 6 años a pesar de las estrategias de intervención para prevención y control de la enfermedad implementadas nivel nacional. Este trabajo busca establecer la línea de base para la población asegurada en Colombia, frente a la supervivencia de pacientes en terapia de remplazo renal (TRR).
Resumo:
Antecedentes: El síndrome de Sjögren (SS) es una patología crónica, autoinmune, de características multifactoriales en su etiología. También es conocida como una epitelitis autoinmune, caracterizada por síntomas secos como xeroftalmia y xerostomía, pero que también puede tener compromiso sistémico, dado por manifestaciones extra-glandulares. En la actualidad es poco reconocida como tal, y por lo tanto, la tasa de sobrevida en estos pacientes se encuentra disminuida pero poco tenida en cuenta a la hora de la valoración de ellos. Este trabajo describe la evidencia encontrada acerca de las causas de mortalidad y sus factores asociados luego de realizar una revisión sistemática de la literatura. Objetivos: El objetivo de este estudio fue reunir de forma exhaustiva y sistemática toda la evidencia empírica, publicada o no, que cumpla los criterios de búsqueda y elegibilidad sobre factores asociados al incremento de la mortalidad o disminución en la sobrevida de los pacientes con diagnóstico de SS. Métodos: Se realizó una revisión sistemática de la literatura mediante una búsqueda exhaustiva de todos los estudios publicados en las bases de datos electrónicas preestablecidas, hasta abril de 2015, con el fin de determinar las causas más frecuentes de mortalidad en pacientes con SS y los factores asociados a ella. Resultados: Se encontraron 4,654 resultados que coincidían con los criterios de búsqueda establecidos; de estos, 33 cumplieron con los criterios de inclusión y se distribuyeron de la siguiente forma: el 66.6% (22/33) correspondieron a estudios de corte cohorte, 30.3% (10/33) a estudios de corte transversal y el 3.03% (1/33) a estudios casos y controles. Se obtuvieron resultados en cuanto a frecuencias de mortalidad, razón estandarizada de mortalidad, tasas de supervivencia, causas más frecuentes de mortalidad y sus factores asociados. Conclusiones: La mortalidad reportada en los diferentes estudios fue entre el 1.2% hasta el 30%. Aquellos estudios que reportaron una tasa de mortalidad inferior al 5%, tuvieron un tiempo de seguimiento menor 8 años [1,7,33,60,64,86]. La mayoría de los casos sigue un curso relativamente estable, pero hay un porcentaje importante que presenta otras manifestaciones sistémicas con mayor frecuencia de complicaciones durante la evolución del SS. Por tanto, son los que requieren un seguimiento más estrecho, debido a una mayor necesidad de tratamiento sistémico y al mayor riesgo de ingreso hospitalario y de mortalidad, especialmente por el desarrollo de procesos linfoproliferativos B. La presencia de factores pronósticos en el paciente con SS obligará a realizar un seguimiento clínico e inmunológico mucho más estrecho, lo cual permitirá identificar lo antes posible las complicaciones que puedan aparecer e instaurar las correspondientes medidas terapéuticas, para aumentar las tasas de supervivencia.
Resumo:
Background: Balloon pulmonary angioplasty (BPA) has recently been developed as an alternative and less- invasive treatment strategy for chronic thromboembolic pulmonary hypertension (CTEPH), but therapeutic efficacy and technical safety of the technique have to be established. Aim: effects of BPA on patients with inoperable disease or residual pulmonary hypertension (PH) after pulmonary endarterectomy (PEA). Methods: From June 2015 to September 2019 we enrolled symptomatic (NYHA ≥ II) inoperable CTEPH patients and patients with residual PH after PEA. At baseline, immediately before the first BPA session and 3-6 months after last BPA session all patients underwent clinical evaluation, six-minute walking distance and right heart catheterization. For comparisons Friedman test (with Bonferroni post-hoc pairwise analysis) was used. Survival curves were done with Kaplan Meier method. Results: Forty-seven patients [male 45%, median age 68 (51-74) years, 40 inoperable and 7 with residual PH after PEA] were treated for a total of 136 sessions (median number of sessions for each patient: 2); during each session we treated 2 (2-3) vessels; BPA significantly improved symptoms (NYHA III-IV from 85 to 42%), exercise capacity (from 425 to 446 m) and hemodynamic profile (reduction of mean pulmonary arterial pressure from 41 to 35 mmHg and of pulmonary vascular resistance from 7.1 to 4.7 WU). Five pulmonary artery dissection and 2 hemoptysis with clinical impairment were documented; 33 patients had lung injury (radiographic opacity with/without hemoptysis and/or hypoxemia), 7 patients had access site complications. Five patients died during follow-up (none within 30 days from the procedure) because of sepsis (1), heart failure (1), cancer (1), arrhythmic storm (1) and sudden death in a patient with severe coronary atherosclerosis (1). Conclusions: BPA is a safe and effective treatment able to improve symptoms and hemodynamic profile in inoperable CTEPH patients and in patients with residual PH after PEA.
Resumo:
L'utilità clinica dell’uso routinario delle tecniche di sequenziamento di nuova generazione (NGS) nei pazienti con cancro colorettale metastatico andrebbe approfondita. In questo studio, è stato valutato l'impatto di un pannello NGS da 52 geni utilizzato nella pratica clinica di routine. Abbiamo analizzato i risultati dei test molecolari multigenici in pazienti con carcinoma colorettale metastatico (mCRC) in uno studio osservazionale, retrospettivo e monocentrico su pazienti affetti da carcinoma colorettale metastatico consecutivamente testati presso un centro oncologico italiano tra giugno 2019 e dicembre 2020. Le analisi di sopravvivenza sono state effettuate con il metodo Kaplan-Meier, test log-rank e modello di Cox. Complessivamente sono stati inclusi 179 pazienti con mCRC. Il follow-up mediano è stato di 33 mesi (IQR: 28,45–NR). I quattro geni più frequentemente mutati sono stati: KRAS (48,6%), PIK3CA (22,4%), BRAF (14,5%) e APC (8,4%). È stata trovata un'associazione positiva tra la sopravvivenza globale (OS) e le mutazioni KRAS con un'alta frequenza allelica variante (VAF) [HR: 0,60 (0.36 – 0.99), P=0.047]. La mutazione BRAF era associata a OS inferiore [HR: 2,62 (1,59-4,32), P <0,001]. Il panello NGS ha consentito a otto pazienti di accedere a terapie a bersaglio molecolare non ancora registrate per il cancro colorettale. In conclusione, i pannelli NGS in mCRC sono fattibili nella pratica clinica in laboratori di riferimento per consentire un impatto inferiore sui costi e un aggiornamento regolare. La mutazione di BRAF risulta associata a una prognosi peggiore. Le mutazioni di KRAS con un’elevata variazione di frequenza allelica erano associate a una sopravvivenza globale superiore rispetto ai pazienti KRAS non mutati. Sono necessari studi più approfonditi per analizzare meglio i fattori prognostici.
Resumo:
Introduzione Nel 2014 è stato proposto un protocollo di studio riguardante la sorveglianza delle lesioni cistiche del pancreas (intese come IPMN) e denominato PACYFIC Study. Obiettivi Obiettivo primario era di stabilire l’impatto di un programma di sorveglianza in termini di pazienti arruolati e pazienti con indicazione chirurgica. Obiettivi secondari erano: 1) stabilire l’impatto dei fattori demografici, clinici, radiologici e della strategia di sorveglianza sull’indicazione chirurgica, sulla capacità individuare le lesioni maligne, sulla sopravvivenza. Materiali e Metodi Lo studio su cui si è basata la raccolta dei dati è uno studio di tipo prospettico, di coorte, multicentrico, internazionale. Lo studio ha incluso gli individui con una IPMN, di nuova o pregressa diagnosi, che giustifichi una sorveglianza o il trattamento chirurgico. I dati clinici, demografici, radiologici e chirurgici sono stati raccolti in un database prospettico. Le variabili discrete sono state espresse come frequenza e percentuale. Le continue come medie e deviazioni standard o mediane e range interquartile (IQR). Per l’analisi statistica sono stati utilizzati il test di Fischer, il test del Chi quadro, il test di Spearman, il test di Student. L’analisi multivariata è stata eseguita utilizzando la regressione logistica espressa come Odds Ratio e intervallo di confidenza al 95 %. Per la sopravvivenza è stato utilizzato il metodo di Kaplan-Meier. L’analisi multivariata sulle sopravvivenze è stata eseguita mediante la regressione di Cox. Risultati Il protocollo di sorveglianza ha permesso l'arruolamento di 516 pazienti. 53 pazienti hanno raggiunto l'indicazione chirurgica. La sopravvivenza globale della coorte è stata di 326.8± 9.1 mesi. I fattori predittivi la sopravvivenza sono risultati età (OR 1.07, P-value<0.001), sesso (OR 1.82, P-value=0.006), ittero, noduli murali (OR 4.84, P-value=0.018 e OR 2.19, P-value=0.016), chirurgia (OR 0.46, P-value 0.038). Conclusioni L'introduzione del protocollo di sorveglianza ha portato ad un aumento di identificazione di lesioni e ha avuto impatto sulla sopravvivenza
Resumo:
Purpose: To evaluate overall and relapse-free survival (RFS) in patients with nonmycosis fungoides (non-MF) primary cutaneous lymphoma (PCL). Methods: Thirty-eight patients with PCL excluding cases of MF treated between 1993 and 2006 were analyzed retrospectively. Survival statistics were estimated by the methods of Kaplan and Meier, and univariate and multivariate significance testing were performed by Cox regression analysis. Results: The median follow-up was 34.6 months (range, 2-138.3 months). The overall survival for the entire study population, at 5 and 10 years, was 97% and 78%, respectively. The RFS for the entire study population, at 5 and 10 years, was 30% and 22%, respectively. For those who received radiotherapy (RT) as a component of their initial therapy, the RFS at 5 and 10 years was 48% and 36%, respectively. Among those receiving RT who relapsed, the site of relapse was out-of-field in 82% of the cases. In our multivariate analysis, only RT as a component of the initial therapy and the absence of bulky disease had a statistically significant improvement in RFS (P = 0.01 and < 0.01, respectively). Conclusion: RT improves the local control and RFS of patients with non-MF PCL.
Resumo:
Inúmeros experimentos em ciências agrárias apresentam variáveis que podem dar origem a problemas de multicolinearidade. Em se tratando da aplicabilidade de modelos de regressão, o problema da multicolinearidade tem como principal consequência o inflacionamento dos erros padrão e, com isso, o valor da estatística t-student é reduzido de tal forma que interfere nos resultados inferenciais. Várias medidas são propostas, na literatura, para resolver o problema de multicolinearidade. Entretanto, o desempenho dessas medidas está sujeito ao grau de multicolinearidade que as variáveis poderão apresentar, bem como ao tamanho amostral. Frente a este problema, este trabalho tem por objetivo avaliar alguns estimadores ridge, utilizando simulação Monte Carlo, bem como, apresentar a aplicação desses estimadores em um experimento, com dados reais, na área de entomologia. Mediante esta aplicação, os resultados expressivos alcançados foram obtidos em função da eficiência dos estimadores ridge avaliados, em relação ao estimador de mínimos quadrados. Em se tratando dos resultados computacionais, concluiu-se que estimadores ridge avaliados são recomendáveis, em experimentos que considerem as variáveis com diferentes graus de multicolinearidade, para amostras maiores do que n=50.
Resumo:
The impact of clinical, pathologic, and surgical variables on the postoperative morbidity, mortality, and survival of patients undergoing extended resections of colon carcinoma were evaluated. METHODS: The medical records of 95 patients who underwent extended resections for colon carcinoma between 1953 and 1996 were reviewed. In all cases, in addition to colectomy, 1 or more organs and/or structures were resected en bloc due to a macroscopically based suspicion of tumor invasion. The clinical, pathologic, and surgical parameters were analyzed. Overall survival rates were analyzed according to the method of Kaplan and Meier. Multivariate analysis was performed using the Cox proportional hazards model. RESULTS: Eighty-six patients were treated by curative surgeries and the remaining by palliative resections. Invasion of the organs and/or adjacent structures and regional lymph nodes was found microscopically in 48 and 31 patients, respectively. The median follow-up without postoperative mortality was 47.7 months. The 5-year overall survival rates was 52.6%. The 5-year overall survival rates for patients undergoing curative and palliative surgeries was 58.3% and 0%, respectively. The mean survival time in the palliative surgery group was 3.1 months. Multivariate analysis showed that Karnofsky performance status was strongly related to the risk of postoperative complications (P = .01), and postoperative deaths were associated with the type of surgery and Karnofsky performance status at the time of admission (P = .001). CONCLUSIONS: Some patients with locally advanced colon adenocarcinomas undergoing extended resections have a 5-year overall survival rates of 58.3%. Patients could benefit from palliative-intent procedures, but these measures should cautiously be indicated and avoided in patients with low Karnofsky performance status due to high rates of postoperative mortality and poor survival.
Resumo:
Background: To describe the overall and disease-free survival at five and ten years after breast cancer diagnosis in women from a previous case-control study, and establish related prognostic factors. Methods: We followed up 202 patients diagnosed between 1996 and 1998 in three public hospitals in Granada and Almeria provinces in Spain. Survival rates were calculated using the Kaplan and Meier method, and the Cox proportional hazards model was applied to identify the most significant variables contributing to survival. Results: Mean age at diagnosis was 54.27±10.4 years. Mean follow-up for overall survival was 119.91 months (95%CI 113.65126.17); the five-year survival rate was 83.9% (95%CI: 78.13-89.66) and the ten-year rate was 71% (95%CI: 63.25-78.74). Mean followup for disease-free survival was 118.75 months (95%CI 111.86125.65); the five-year disease-free survival rate was 81% (95%CI: 74.52-87.47) and the ten-year rate was 71.3% (95%CI: 63.33-79.26). The mortality rate of the study population was 33.17%. Conclusions: Disease characteristics are similar in our population to those in other Spanish and European regions, while the overall survival is higher than the mean rate during the same period in Europe (5-yr rate of 79%) and similar to that in Spain (83%).
Resumo:
This work is part of a project studying the performance of model basedestimators in a small area context. We have chosen a simple statisticalapplication in which we estimate the growth rate of accupation for severalregions of Spain. We compare three estimators: the direct one based onstraightforward results from the survey (which is unbiassed), and a thirdone which is based in a statistical model and that minimizes the mean squareerror.
Resumo:
Introduction : Bien que rares chez l'adulte, les sarcomes des tissus mous restent une maladie au pronostic très sombre. En effet, leur survie globale à 5 ans est de 50 % chez la femme et de 41 % chez l'homme. De plus, ils sont particulièrement difficiles à traiter, en raison de leur agressivité, de leur résistance face aux chimiothérapies et à la radiothérapie et d'autre part leur localisation conduit souvent à des opérations mutilantes. Pour les sarcomes des membres, il existe une opération appelée perfusion isolée du membre (ILP). Cela consiste à réaliser une chimiothérapie par voie intra-artérielle, en isolant le membre qui est perfusé par une solution Melphalan et de Tumor Necrosis Factor α à l'aide d'une circulation extra-corporelle pour son oxygénation. Ce type de traitement est à visée palliative, évitant une amputation du membre atteint. Pour accéder aux vaisseaux permettant la canulation de la pompe, un curage ganglionnaire est généralement effectué. Patients et méthode : Pour cette étude rétrospective, nous avons analysé la base de données des 278 ILP réalisées au Centre Hospitalier Universitaire Vaudois (CHUV) à Lausanne depuis mai 1988. Nous avons extrait et analysé de cette étude rétrospective 57 ILP réalisées pour des sarcomes. L'étude porte sur 52 patients traités entre le 19 février 1992 et le 14 décembre 2011, après avoir exclu les patients n'ayant pas bénéficié d'un curage ganglionnaire et la seconde ILP pour 4 patients qui en ont eu 2. Pour chacun de ces patients, les protocoles opératoires, les rapports d'examens radiologiques ainsi que les rapports de pathologies ont été revus et analysés. Nous avons également effectué une revue de la littérature sur PubMed. Résultats : Il y avait 28 hommes (53.8%) et 24 femmes (46.2 %). L'âge moyen au moment de l'ILP était de 56,7 ans (écart-type 16,8). Seul 3 patients sur les 52 avaient des métastases à distance au moment du diagnostic. Le curage ganglionnaire radical a montré que 13 patients (25 %) avaient une atteinte des ganglions lymphatiques (N+). Parmi les types histologiques qui ont présenté au moins une métastase ganglionnaire, on retrouve 2 léomyosarcomes, 2 sarcomes indifférenciés (anciennement MFH), 3 sarcomes épithélioïdes, 4 angiosarcomes et 2 synoviosarcomes. Pour les patients N0, la survie globale moyenne estimée par la méthode de Kaplan et Meier a été de 95,98 mois (CI 95% 66,72-125,23 mois). Pour les patients N1 la survie globale moyenne a chuté à 28,72 mois (CI 95% 6,48-50,97). Le test du Log Rank donne un Chi2 de 9,659 (P=0,002). La moyenne de survie sans maladie a été de 38,03 mois pour le groupe (N0) et de 10,87 mois pour le groupe N1, (CI 95 % 25,75-50,3 et 1,87-19,88 respectivement) et une valeur de P= 0.006. Nous n'avons pas mis en évidence de différence de survie statistiquement significative (P=0.946) entre les types ou les grades histologiques, en raison de la taille du collectif. Conclusion : Bien que rares, les métastases ganglionnaires des sarcomes des membres ont un impact négatif sur la survie à long terme du patient. Les résultats obtenus montrent qu'un curage peut participer au traitement régional et confirme la nécessité de pratiquer systématiquement une lymphadénectomie radicale en vue d'offrir les meilleures chances de survie au patient. Il faudrait donc se poser la question si la présence de métastases ganglionnaires ne devrait pas modifier la prise en charge pour tendre vers un traitement plus agressif chez de tels patients. Ce qui n'est pas le cas à l'heure actuelle.
Resumo:
O objetivo do trabalho foi comparar, por meio de simulação, as estimativas de componentes de variância produzidas pelos métodos ANOVA (análise da variância), ML (máxima verossimilhança), REML (máxima verossimilhança restrita) e MIVQUE(0) (estimador quadrático não viesado de variância mínima), no delineamento de blocos aumentados com tratamentos adicionais (progênies) de uma ou mais procedências (cruzamentos). Os resultados indicaram superioridade relativa do método MIVQUE(0). O método ANOVA, embora não tendencioso, apresentou as estimativas de menor precisão. Os métodos de máxima verossimilhança, sobretudo ML, tenderam a subestimar a variância do erro experimental () e a superestimar as variâncias genotípicas (
), em especial nos experimentos de menor tamanho (n<120 observações). Quando as progênies vieram de um só cruzamento, REML praticamente perdeu estes vícios nos experimentos maiores e com razões
/
>0,5. Contudo, o método produziu as piores estimativas de variâncias genotípicas quando as progênies vieram de diferentes cruzamentos e os experimentos foram pequenos.