Survival Analysis (survival + analysis)

Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Survival Analysis

  • kaplan-meier survival analysis
  • meier survival analysis
  • multivariate survival analysis

  • Terms modified by Survival Analysis

  • survival analysis methods
  • survival analysis statistics

  • Selected Abstracts


    SENSORY SHELF-LIFE ESTIMATION OF ALFAJOR BY SURVIVAL ANALYSIS

    JOURNAL OF SENSORY STUDIES, Issue 6 2004
    ADRIANA GÁMBARO
    ABSTRACT Survival analysis methodology was used to estimate the shelf life of alfajor (a chocolate-coated individually wrapped cake) at 20 and 35C by using results obtained from consumers when asked if they would accept or reject samples with different storage times. Sensory acceptability (measured by consumers), off-flavor (measured by a trained panel) and moisture content were linearly related to time. These correlations were used to estimate values at the shelf-life times calculated for 25 and 50% rejection probability. Survival analysis provided the following shelf-life estimation: 74 days at 20C and 33 days at 35C for a 25% of rejection, 87 days at 20C and 39 days at 35C for a 50% of rejection. An alfajor stored at 20C having an acceptability value below 4.9 (1,9 hedonic scale) and off-flavor intensity above 5.3 (0,10 scale) would be rejected by 25% of the consumers. Chemical data were not good shelf-life predictors. [source]


    Nursing Diagnoses in Children With Congenital Heart Disease: A Survival Analysis

    INTERNATIONAL JOURNAL OF NURSING TERMINOLOGIES AND CLASSIFICATION, Issue 4 2007
    Viviane Martins Da Silva RN
    First page of article [source]


    Survival Analysis Applied to Sensory Shelf Life of Yogurts,I: Argentine Formulations

    JOURNAL OF FOOD SCIENCE, Issue 7 2005
    Ana Curia
    ABSTRACT: :Sensory shelf lives of Argentine commercial stirred yogurts of different compositions stored at 10 °C were studied. Variations were as follows: fat-free and whole-fat, and vanilla and strawberry flavors. Yogurts were tested between 0 and 84 d of storage by consumers who expressed their acceptance or rejection of each sample; yogurts also were measured overall, as well as their attribute acceptability, with a hedonic scale. Survival analysis statistics were used to estimate shelf lives. Considering 25% of consumers rejecting the product, shelf lives were between 28 and 41 d; thus, a unique shelf life for this product does not seem reasonable. A log-linear model and a direct quantile comparison formula were introduced to analyze the effect of formulation on rejection time distributions and shelf life values, respectively. Overall, fat-free yogurts had lower shelf lives than whole-fat yogurts. [source]


    Survival Analysis Applied to Sensory Shelf Life of Yogurts,II: Spanish Formulations

    JOURNAL OF FOOD SCIENCE, Issue 7 2005
    Ana Salvador
    ABSTRACT: Sensory shelf lives of commercial Spanish yogurts stored at 10 °C were studied. Yogurts were strawberry flavored and differed in fat content (free and whole-fat) and consistency (stirred and set-style). Yogurts were tested between 0 and 90 d of storage by consumers who expressed acceptance or rejection of each sample and measured overall and attribute acceptability on a 9-point hedonic scale. Survival analysis statistics were used to estimate sensory shelf lives. Considering 25% of consumers rejecting the product, shelf lives varied from 38 to 69 d, depending on the composition, so if useful life were to be established using sensory criteria, a single shelf life for yogurt would not appear to be very appropriate. A log-linear model and a direct quantile comparison formula were introduced to analyze the effect of formulation on rejection time distributions and shelf life values, respectively. Fat-free yogurts had shorter shelf lives than whole-fat yogurts. Acceptability of yogurts measured on a 9-point hedonic scale varied less than percentage rejection over the storage times. [source]


    The Relationships of the Level of Response to Alcohol and Additional Characteristics to Alcohol Use Disorders Across Adulthood: A Discrete-Time Survival Analysis

    ALCOHOLISM, Issue 9 2009
    Ryan S. Trim
    Background:, A low level of response (LR) to alcohol has been shown to relate to a higher risk for alcohol use disorders (AUDs). However, no previous research has examined the association between LR and the development of AUDs in the context of additional robust risk factors for AUDs. This study evaluated whether LR and other related characteristics predicted the occurrence of AUDs across adulthood using discrete-time survival analysis (DTSA). Methods:, A total of 297 probands from the San Diego Prospective Study reported on the LR to alcohol, a family history (FH) of AUDs, the typical drinking quantity, the age of drinking onset, the body mass index and the age at the baseline (T1) assessment. Alcohol use disorders (AUDs) were evaluated at the 10-year (T10), T15, T20, and T25 follow-ups. Results:, A low LR to alcohol predicted AUD occurrence over the course of adulthood even after controlling for the effects of other robust risk factors. Interaction effects revealed that the impact of FH on AUDs was only observed for subjects with high T1 drinking levels, and probands with high T1 drinking were at high risk for AUDs regardless of their age of onset. Conclusions:, The findings illustrate that LR is a unique risk factor for AUDs across adulthood, and not simply a reflection of a broader range of risk factors. The continued investigation of how LR is related to AUD onset later in life will help inform treatment providers about this high-risk population, and future longitudinal evaluations will utilize DTSA to assess rates of AUD remission as well as the onset of drinking outcomes in adolescent samples. [source]


    Survival Analysis for Epidemiologic and Medical Research.

    BIOMETRICAL JOURNAL, Issue 2 2009

    No abstract is available for this article. [source]


    Survival Analysis for Epidemiologic and Medical Research by SELVIN, S.

    BIOMETRICS, Issue 2 2009
    M. G. Valsecchi
    No abstract is available for this article. [source]


    Applied Survival Analysis: Regression Modeling of Time-to-Event Data, 2nd edition by HOSMER, D. W., LEMESHOW, S., and MAY, S.

    BIOMETRICS, Issue 2 2009
    Article first published online: 28 MAY 200
    No abstract is available for this article. [source]


    Efron-Type Measures of Prediction Error for Survival Analysis

    BIOMETRICS, Issue 4 2007
    Thomas A. Gerds
    Summary Estimates of the prediction error play an important role in the development of statistical methods and models, and in their applications. We adapt the resampling tools of Efron and Tibshirani (1997, Journal of the American Statistical Association92, 548,560) to survival analysis with right-censored event times. We find that flexible rules, like artificial neural nets, classification and regression trees, or regression splines can be assessed, and compared to less flexible rules in the same data where they are developed. The methods are illustrated with data from a breast cancer trial. [source]


    Discussion of Double Sampling for Survival Analysis

    BIOMETRICS, Issue 2 2001
    Stuart G. Baker
    No abstract is available for this article. [source]


    Survival Analysis in Clinical Trials: Past Developments and Future Directions

    BIOMETRICS, Issue 4 2000
    Thomas R. Fleming
    Summary. The field of survival analysis emerged in the 20th century and experienced tremendous growth during the latter half of the century. The developments in this field that have had the most profound impact on clinical trials are the Kaplan-Meier (1958, Journal of the American Statistical Association53, 457,481) method for estimating the survival function, the log-rank statistic (Mantel, 1966, Cancer Chemotherapy Report50, 163,170) for comparing two survival distributions, and the Cox (1972, Journal of the Royal Statistical Society, Series B34, 187,220) proportional hazards model for quantifying the effects of covariates on the survival time. The counting-process martingale theory pioneered by Aalen (1975, Statistical inference for a family of counting processes, Ph.D. dissertation, University of California, Berkeley) provides a unified framework for studying the small- and large-sample properties of survival analysis statistics. Significant progress has been achieved and further developments are expected in many other areas, including the accelerated failure time model, multivariate failure time data, interval-censored data, dependent censoring, dynamic treatment regimes and causal inference, joint modeling of failure time and longitudinal data, and Baysian methods. [source]


    Comparative efficacy of rapid-release nicotine gum versus nicotine polacrilex gum in relieving smoking cue-provoked craving

    ADDICTION, Issue 11 2005
    Raymond Niaura
    ABSTRACT Aims Most relapse episodes occur when smokers are confronted with craving provoked by situational cues. Current nicotine gum can help relieve cue-provoked cravings, but faster effects may result in more rapid relief. We tested a prototype formulation of a new rapid-release nicotine gum (RRNG) that provides more rapid release and absorption of nicotine, for its ability to provide faster and better craving relief compared to current nicotine polacrilex gum (NPG). Design Random assignment to RRNG or NPG, used during a smoking cue provocation procedure. Participants and setting A total of 319 smokers were exposed to a smoking cue in the laboratory by being asked to light but not smoke a cigarette of their preferred brand. Subjects then chewed a piece of 2 mg RRNG (n = 159) or 2 mg NPG (n = 160) according to randomized assignment. Measurements Craving assessments were completed at regular intervals before and after cue exposure (baseline, pre-cue, and 3, 6, 9, 12, 15, 18, 21, 25, 30 and 35 minutes after the cue). Findings Smokers chewing RRNG showed significantly lower craving than NPG subjects starting with the first assessment at 3 minutes (P < 0.025). Repeated-measures ANOVA revealed a significant treatment × time interaction (P < 0.05),craving scores dropped more rapidly in RRNG subjects compared to NPG subjects. Survival analyses also indicated superiority of RRNG in achieving more rapid self-reported meaningful relief (P < 0.05) and complete relief (P < 0.05) of craving. Conclusions Rapid-release nicotine gum reduced cue-provoked craving more rapidly compared to NPG, and thus merits further study in cessation efficacy trials. [source]


    Hepatic resection compared to percutaneous ethanol injection for small hepatocellular carcinoma using propensity score matching

    JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 10 2007
    Yong Beom Cho
    Abstract Background:, Several surgical and non-surgical therapeutic modalities have been used for the treatment of hepatocellular carcinoma (HCC). There have been several studies comparing hepatic resection (HR) and percutaneous ethanol injection (PEI) for the treatment of HCC. However, there is still disagreement about the best treatment modality. Methods:, From 130 patients undergoing HR, 116 patients were individually matched to 116 controls from 249 patients undergoing PEI using propensity score matching to overcome possible biases in non-randomized study. Survival analyses were undertaken to compare these propensity score-matched groups. Results:, After matching by propensity score, the major clinical outcomes in the HR (n = 116) and the PEI (n = 116) groups were found to be similar. The 1-, 3- and 5-year overall survival rates were higher in the HR group (94.8%, 76.5% and 65.6%) compared to the PEI group (95.7%, 73.5% and 49.3%) (P = 0.059). The cumulative 1-, 3- and 5-year disease-free survival rates showed the same trend (HR: 76.1%, 50.6% and 40.6%; PEI: 62.6%, 25.5% and 19.1%) (P < 0.001). However, when stratified by Child,Pugh classification, it was no longer the case in the Child B patients. Single intrahepatic recurrence was the most common pattern of tumor recurrence after both treatments. Conclusions:, Patients undergoing HR had a better survival profile than those undergoing PEI. However, when considering which technique to use for optimal HCC management, the individual patient's hepatic function must be considered. [source]


    Alcohol Dependence and Reproductive Onset: Findings in Two Australian Twin Cohorts

    ALCOHOLISM, Issue 11 2008
    Mary Waldron
    Background:, Although early alcohol use is a strong predictor of future alcohol problems and adolescent drinking is associated with risky sexual behavior predictive of early childbearing, reproductive dysfunctions associated with delayed childbearing have been reported in adult drinkers. We examine the relationship between lifetime history of alcohol dependence (AD) and timing of first childbirth across reproductive development. Methods:, Data were drawn from two cohorts of Australian twins born between 1893 and 1964 (3634 female and 1880 male twins) and between 1964 and 1971 (3381 female and 2748 male twins). Survival analyses were conducted using Cox proportional hazards regression models predicting age at first childbirth from AD, with sociodemographic characteristics, regular smoking, history of psychopathology, and family and childhood risks included as control variables in adjusted models. Results:, Results suggest alcoholic women in both cohorts show overall delayed reproduction, with little effect of AD on timing of first reproduction in men. Effects of AD are particularly strong for women in the older cohort, where AD is associated with 73% decreased likelihood of first childbirth after age 29 [hazard ratio (HR) = 0.27, 95% CI: 0.10,0.75]. In adjusted models, effects reduce only slightly (HR = 0.29, 95% CI: 0.11,0.80). For women in the young cohort, AD is associated with delayed reproduction after age 24, with 40% decreased likelihood of first childbirth (HR = 0.60, 95% CI: 0.48,0.75). AD remains predictive in adjusted models, but without age interaction (HR = 0.72, 95% CI: 0.62,0.85). Conclusions:, Findings of delayed reproductive onset in alcoholic women are consistent with alcohol-related reproductive dysfunctions, although underlying mechanisms remain largely unknown. To better understand AD differences in reproductive onset, continued research on both biological and psychosocial risks is needed. [source]


    Impact of primary tumour stage on survival in dogs with solitary lung tumours

    JOURNAL OF SMALL ANIMAL PRACTICE, Issue 2 2008
    G. A. Polton
    Objectives: The objective of this study was to determine simple prognostic criteria for differentiation of canine solitary lung tumour cases into those that will and will not benefit from thoracic surgery. Methods: This was a retrospective study using the records of cases presented to Davies Veterinary Specialists, Hitchin, UK, from December 1998 to December 2005. Survival analyses were performed using the Kaplan-Meier and logrank methods. Potentially significant variables were evaluated by multivariate Cox analysis. Results: Forty-two patients met the inclusion criteria. Primary tumour stage T1, absence of neoplastic lymph nodes and metastases, and papillary tumour type were statistically significant favourable prognostic indicators on univariate analysis. Multivariate analysis attributed significance to primary tumour stage T1 and papillary type only. Median survival times were 555 days for T1N0M0 tumours of papillary type and 72 days for the remainder. Clinical Significance: Survival time following surgery in dogs with primary lung tumours was poor except in clinical stage T1N0M0 cases. These data support use of clinical techniques to dichotomise cases as T1N0M0 or other, improving decision making in thoracic surgery. These data validate initiation of prospective studies examining the role of chemotherapy in the management of advanced cases. [source]


    Site and clinical outcome of deep vein thrombosis of the lower limbs: an epidemiological study

    JOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 7 2005
    C. SEINTURIER
    Summary., Clinical outcomes of patients diagnosed with venous thromboembolic disease (VTED) have rarely been assessed on large series of patients from single institutions. This was work based on our practice to routinely screen all suspected pulmonary embolism (PE) and deep venous thrombosis (DVT) patients with bilateral proximal and distal venous US was designed to evaluate survival, recurrence and cancer occurrence in patients diagnosed with symptomatic or asymptomatic DVT and to assess their relationship with the site of the DVT (proximal vs. distal, bilateral vs. unilateral). Our study is based on the cross-matching of the VTED register of the Grenoble University Hospital with the local Cancer Register and community mortality data. Survival analyses were performed with the Kaplan,Meier method; prognostic variables were tested using the log,rank test. A total of 1913 patients with a DVT of the lower limbs from 1993 to 1998 were included (57% women; mean age, 69 years). Of these, 1018 patients were diagnosed with proximal DVT (156 bilateral) and 895 distal DVT (112 bilateral). PE was associated in 760 patients. Patients with PE and no detected DVT were not included. At 2 years, adjusted survival rates were 80% in patients with unilateral-distal DVT, 67% in bilateral-distal, 72% in unilateral-proximal and 65% in bilateral-proximal DVT patients. The cumulated VTED recurrence rates were 7.7% in unilateral-distal DVT, 13.3% when DVT was bilateral-distal, 14% when unilateral-proximal and 13.2% when bilateral-proximal. The rate of new cancer was 6.4% in unilateral-distal DVT, 10.8% when it was bilateral-distal, 6.5% when unilateral-proximal and 6.1% when bilateral-proximal. Based on a large series of unselected patients, our results show that the site of the DVT and principally the bilaterality provides important prognostic information that may be used in the setting up of medical strategies. [source]


    OUTCOMES AFTER OESOPHAGOGASTRECTOMY FOR CARCINOMA OF THE OESOPHAGUS

    ANZ JOURNAL OF SURGERY, Issue 1-2 2007
    Mark Omundsen
    Background: Carcinoma of the oesophagus is a rare but a highly lethal malignancy. The incidence of adenocarcinoma in particular is increasing in the Western world. Despite improvements in staging, perioperative care and the use of adjuvant/neoadjuvant regimen the prognosis remains poor. Methods: All patients who had biopsy-proven oesophageal carcinoma between the years 1992 and 2004 in the Wellington region, New Zealand, were retrospectively reviewed. The personal and tumour characteristics, operation details, complications and the details of hospital stay of patients who had had a resection were recorded in a database . Survival data were recovered from the notes, hospital database or general practitioner records and were available for all patients who had surgery. Survival analyses were calculated using Kaplan,Meier estimates. Results: One hundred and ninety-one patients were diagnosed with oesophageal carcinoma during the study period (59% adenocarcinoma, 32% squamous cell carcinoma). Only 35% (n = 67) had a resection (81% adenocarcinoma, 13% squamous cell carcinoma). Fifty-one (77%) had an Ivor Lewis procedure, 9 (14%) had only a laparotomy and 6 (9%) had a laparotomy, right thoracotomy and cervical incision. Forty-six (70%) tumours were in the distal third of the oesophagus and 13 (20%) were at the oesophagogastric junction. Perioperative mortality was 10% (n = 7) and anastomotic leak rate 9% (n = 6). Five-year survival was 23%. Conclusion: Results from our institution for the resection of oesophageal cancer compare favourably with those in the published work. Staging with computed tomography and laparoscopy has resulted in acceptable resection and survival rates. Survival for this disease is still largely stage dependent and earlier diagnosis probably holds the key to improved prognosis. [source]


    Depression predicts unfavourable functional outcome and higher mortality in stroke patients: The Bergen Stroke Study

    ACTA NEUROLOGICA SCANDINAVICA, Issue 2010
    H. Naess
    Naess H, Lunde L, Brogger J, Waje-Andreassen U. Depression predicts unfavourable functional outcome and higher mortality in stroke patients: The Bergen Stroke Study. Acta Neurol Scand: 2010: 122 (Suppl. 190): 34,38. © 2010 John Wiley & Sons A/S. Objective,,, To assess the influence of depression prior to stroke (PD) on stroke severity on admittance, functional outcome (short- and long-term), mortality, and long-term depression (PSD). Methods,,, Consecutive acute stroke patients were screened for PD. The National Institute of Health Stroke Scale score was obtained on admission. Short-term functional state was registered by the modified Rankin scale and on long-term functional outcome by the Barthel Index. PSD was defined as depression subscale of the hospital anxiety and depression scale (HADSD) ,11. HADSD and Barthel Index were obtained by postal questionnaire. Survival analyses were performed. Results,,, Among 771 patients 21.7% had PD. Among 376 patients returning the questionnaire, 8.8% were depressed. On logistic regression analyses severity of stroke on admission, short-term, and long-term functional outcome were independently associated with PD. Logistic regression showed PSD to be independently associated with PD and being unmarried. Cox regression analyses showed that both PD and PSD were associated with high long-term mortality. Conclusions,,, This study has identified several factors associated with PSD. PD predicts more severe stroke on admittance and less functional improvement both in the short- and the long-term. Both PD and PSD predict higher long-term mortality. [source]


    Life expectancy of screen-detected invasive breast cancer patients compared with women invited to the Nijmegen screening program

    CANCER, Issue 3 2010
    Johannes D. M. Otten
    Abstract BACKGROUND: Screening can lead to earlier detection of breast cancer and thus to an improvement in survival. The authors studied the life expectancy of women with screen-detected invasive breast cancer (patients) compared with women invited to the breast cancer screening program in Nijmegen, the Netherlands (comparison group). METHODS: Each patient diagnosed between 1975 and 2006 was randomly age-matched with a woman invited in the same calendar year and free from breast cancer at the time of diagnosis of the patient. Survival analyses were performed to study differences in life expectancy. RESULTS: The life expectancy for 858 patients was 6 years shorter than for the comparison group. However, for 360 patients with small (<15 mm) invasive breast cancer, life expectancy was similar to that of the comparison group. In contrast, for patients detected with larger tumors (,15 mm) the life expectancy was 6 to 12 years shorter, depending on tumor size. Furthermore, life expectancy was modified by screening history. For patients who had a negative screening examination 2 years before the detection of their breast cancer, the difference in life expectancy from the comparison group became smaller for the larger tumor sizes (,15 mm). CONCLUSIONS: In conclusion, about 40% (360 of 858) of all women with invasive screen-detected breast cancer have the same life expectancy as women from the comparison group (reflecting the general population). For women diagnosed with larger tumors at diagnosis, life expectancy diminishes with increasing tumor size and is modified by screening history. Cancer 2010. © 2009 American Cancer Society. [source]


    Risk factors for obesity in childhood survivors of suprasellar brain tumours: a retrospective study

    ACTA PAEDIATRICA, Issue 10 2010
    Ngee Lek
    Abstract Aim:, To characterize postdiagnosis changes in body mass index (BMI) among childhood survivors of suprasellar brain tumours, and to determine the risk factors associated with obesity. Methods:, We conducted a retrospective analysis of 46 children (16 boys and 30 girls) with median (IQR) age of 7.49 (3.47,11.59) years at tumour diagnosis, and followed up for 3.93 (1.68,7.27) years. Survival analyses were used to identify risks of developing obesity. Results:, There were no sex differences in age at tumour diagnosis, duration of follow-up, tumour types, endocrinopathies, treatment modalities or baseline BMI SDS. In the first year after tumour diagnosis, ,BMI SDS (median; IQR) was greater in girls (1.32; 0.07,2.08) than in boys (0.48; ,0.40 to 0.89) (p = 0.01). At diagnosis, 3/46 children (6%) were obese; this increased to 20/46 (43%) by last follow-up (p < 0.001) and was more common in girls (17/30; 57%) than in boys (3/16; 19%). Female gender (hazard ratio 5.0, 95% CI 1.2,21.7; p = 0.04) and greater than average baseline BMI (hazard ratio 4.7, 95% CI 1.1,20.8; p = 0.02) were risk factors for subsequent obesity. Conclusion:, Accurate prediction of obesity risk is important and would allow early targeted intervention in high-risk patients. [source]


    Evaluation of a cognitive behaviourally oriented service for relapse prevention in schizophrenia

    ACTA PSYCHIATRICA SCANDINAVICA, Issue 5 2010
    S. Klingberg
    Klingberg S, Wittorf A, Fischer A, Jakob-Deters K, Buchkremer G, Wiedemann G. Evaluation of a cognitive behaviourally oriented service for relapse prevention in schizophrenia. Objective:, There is little work demonstrating the effectiveness of cognitive behaviourally oriented interventions in routine service settings. This pragmatic trial is designed to test the impact of a group treatment service on relapse rates under the conditions of routine health care. Method:, A total of 169 schizophrenia patients were randomly allocated either to a comprehensive cognitive behaviourally oriented service (CBOS) or to treatment as usual (TAU). The primary outcome is the time until the first relapse after discharge from hospital. Relapse was defined as an increase in positive or negative symptoms as assessed with the Positive and Negative Syndrome Scale. Survival analysis has been conducted up to the 6-month assessment. Results:, The mean time to relapse after discharge from hospital in the CBOS group was significantly longer than in the TAU group (log rank test, P = 0.033). This was due to less exacerbations regarding negative symptoms in the CBOS condition (log rank test, P = 0.014). The number of social contacts was improved in the CBOS group only. Conclusion:, The CBOS intervention appears to be beneficial in reducing early negative symptom exacerbations. [source]


    Early neurodevelopmental markers predictive of mortality in infants infected with HIV-1

    DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 2 2003
    Antolin Llorente PhD
    One-hundred and fifty-seven vertically infected HIV-1 positive infants (85 males, 72 females) underwent longitudinal assessment to determine whether early neurodevelopmental markers are useful predictors of mortality in those infants who survive to at least 4 months of age. Survival analysis methods were used to estimate time to death for quartiles of 4-month scores (baseline) on the Bayley Scales of Infant Development (BSID). Cox proportional hazards progression was used to estimate relative hazard (RH, 95% CI) of death for BSID scores and potential confounders. Thirty infants with BSID scores at 4 months of age died during follow-up. Survival analysis revealed greater mortality rates in infants with BSID (Mental Developmental Index and Psychomotor Developmental Index) scores in the lower quartile(p=0.004,p=0.036). Unadjusted univariate analyses revealed increased mortality associated with baseline CD4+ 29%, gestational age <37 weeks, smaller head circumference, advanced HIV and higher plasma viral load. BSID scores independently predicted mortality after adjusting for treatment, clinical category, gestational age, plasma viral load and CD4+ percentage. [source]


    Factors predictive of nephropathy in DCCT Type 1 diabetic patients with good or poor metabolic control

    DIABETIC MEDICINE, Issue 7 2003
    L. Zhang
    Abstract Aims The study aim was to assess the time-related risk of developing diabetic nephropathy [albumin excretion rate (AER) , 40 mg/24 h] from baseline covariates in Type 1 diabetic patients with either good or poor metabolic control (MC). Methods Based on material from the Diabetes Control and Complications Trial study (n = 1441), patients were considered as under good or poor MC if their HbA1c mean level up to last visit fell in the lowest (, 6.9%) or highest (, 9.5%) quintile of the overall HbA1c distribution, respectively. Prevalence cases of nephropathy were excluded from the study. Survival analysis and Cox regression were applied to the data. Results Among patients with good MC (n = 277), 15% had developed nephropathy at the end of the study. Conversely, among patients with poor MC (n = 268), the proportion without the complication was 52%. When adjusting for MC, time to diabetic nephropathy was related to age (P < 0.0001), AER (P < 0.001), duration of diabetes (P < 0.005), body mass index (BMI) (P < 0.005), all at baseline, and to gender (P < 0.01). Patients with upper normal range AER levels, longer duration of diabetes and lower BMI were at higher risk, regardless of MC. The adverse effect of younger age on diabetic nephropathy was more marked in good than in poor MC. Although women tended to develop the complication more often under good MC, they appeared to be better protected under poor MC. Conclusions This study confirms occurrence of diabetic nephropathy under good MC and non-occurrence of the complication despite poor MC. It also demonstrates that some baseline covariates can affect, in a differential manner, time to diabetic nephropathy depending on MC. Diabet. Med. 20, 580,585 (2003) [source]


    Recurrence after a First Unprovoked Cryptogenic/Idiopathic Seizure in Children: A Prospective Study from São Paulo, Brazil

    EPILEPSIA, Issue 2 2004
    Anna E. Scotoni
    Summary: Purpose: To evaluate the recurrence risk after a first unprovoked seizure in a large population of children and adolescents of a developing country. Methods: This prospective study was conducted at two tertiary hospitals, between September 1989 and August 1998. Children were enrolled if they had a first unprovoked cryptogenic/idiopathic seizure and maximal interval to the enrollment ,90 days. EEG and computed tomography (CT) were performed in most patients. Potential predictors of recurrence were compared by using the Cox proportional hazards model in univariate and multivariate analyses. Survival analysis was performed by using the Kaplan,Meier curves. Results: Two hundred thirteen children were included. Recurrence occurred in 34% of the patients, and mean time for recurrence was 12 months. Statistical analysis showed significance for seizure recurrence only for patients with abnormal EEGs. CT was performed in 182 patients, and abnormalities were found in 9.5%. Small calcifications were the most frequent finding, and this was not a predictor for recurrence. Conclusions: The risk of recurrence after a first unprovoked seizure in children from a developing country is similar to that found in developed countries. An abnormal EEG is a risk factor for seizure recurrence in children with a cryptogenic/idiopathic seizure. Calcifications on CT do not increase the risk of recurrence. [source]


    What is the likelihood that Thoroughbred foals treated for septic arthritis will race?

    EQUINE VETERINARY JOURNAL, Issue 5 2004
    L. J. SMITH
    Summary Reasons for performing study: Septic arthritis is a serious problem in the neonate, with a poor prognosis being reported for recovery. The impact of neonatal septic arthritis on the likelihood that Thoroughbred (TB) foals will start on a racecourse is not known. Hypothesis: The development of septic arthritis in a TB foal significantly reduces the likelihood that it will race when compared to foals from the same dam. Methods: Medical records of 69 foals treated for septic arthritis were reviewed. The dam's foaling records were reviewed and lifetime racing records were then retrieved for both the affected foals and at least one of their siblings (controls). Outcomes that were statistically evaluated included discharge from the hospital and whether the foal eventually raced. Univariate analyses of categorical variables were conducted for each outcome. The number of affected and unaffected foals that raced at least once were compared using regression analysis. Survival analysis was used to compare age at first race between the study and comparison groups. Results: Foals with septic arthritis were less likely to start on a racecourse compared to controls (odds ratio [OR] 0.28; 95% confidence interval [CI] 0.12-0.62, P = 0.001), while those foals that were discharged from the hospital were also less likely to start on a racecourse compared to controls (OR 0.36; CI 0.15,0.83, P = 0.008). The presence of multisystem disease was associated with a decreased likelihood of surviving to be discharged (OR 0.13; 95% CI 0.02-0.90; P = 0.005), but did not affect the likelihood that they would start in at least one race if discharged successfully (OR 0.45; 95% CI 0.04-2.81; P = 0.34) compared to the other foals with septic arthritis. Log-rank comparison of survival curves confirmed that foals discharged following treatment for septic arthritis took significantly longer to start in their first race compared to the sibling population (mean age of study group 1757 days, CI 1604-1909; mean age of sibling group 1273 days, CI 1197-1349; P = 0.0006). Conclusions: The development of septic arthritis in a TB foal significantly reduces the likelihood that it will start on a racecourse when compared to controls. Potential relevance: Accurate figures allowing a realistic assessment of the athletic future of a foal following treatment for septic arthritis are of significance for both owner and treating veterinarian. [source]


    Epidemiologic Analysis of an Urban, Public Emergency Department's Frequent Users

    ACADEMIC EMERGENCY MEDICINE, Issue 6 2000
    Joshua H. Mandelberg BA
    Abstract. Objectives: To determine how the demographic, clinical, and utilization characteristics of emergency department (ED) frequent users differ from those of other ED patients. Methods: A cross-sectional and retrospective cohort study was performed using a database of all 348,858 visits to the San Francisco General Hospital ED during a five-year period (July 1, 1993, to June 30, 1998). A "frequent user" visited the ED five or more times in a 12-month period. Results: Frequent users constituted 3.9% of ED patients but accounted for 20.5% of ED visits. The relative risk (RR) of frequent use was high among patients who were homeless (RR = 4.5), African American (RR = 1.8), and Medi-Cal sponsored (RR = 2.1). Frequent users were more likely to be seen for alcohol withdrawal (RR = 4.4), alcohol dependence (RR = 3.4), and alcohol intoxication (RR = 2.4). Frequent users were also more likely to visit for exacerbations of chronic conditions, including sickle cell anemia (RR = 8.0), renal failure (RR = 3.6), and chronic obstructive pulmonary disease (RR = 3.3). They were less likely to visit for all forms of trauma (RR = 0.43). Survival analysis showed that only 38% of frequent users for one year remained frequent users the next year. However, 56% of frequent users for two consecutive years remained frequent users in the third year. Conclusions: Frequent use of the ED reflects the urban social problems of homelessness, poverty, alcohol abuse, and chronic illness. Frequent use of the ED shows a high rate of decline from one year to the next. This rate of decline slows after the first year and suggests the existence of a smaller group of chronic frequent users. [source]


    Prediction of poor survival by cyclooxygenase-2 in patients with T4 nasopharyngeal cancer treated by radiation therapy: Clinical and in vitro studies

    HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 6 2005
    Wen-Cheng Chen MD
    Abstract Background. This study was undertaken to determine the status of cyclooxygenase-2 (COX-2) in nasopharyngeal cancer (NPC) in Taiwanese patients and its relationship to survival after radiotherapy (RT). In addition, the effect of NS-398, a potent selective COX-2 inhibitor, was tested in vitro alone and in combination with radiation on NPC-BM1 human NPC cells as a prelude to using this drug along with RT in the treatment of patients with NPC. Methods. Thirty-seven patients diagnosed with T4N0,3M0 NPC were enrolled into this study. COX-2 expression was determined by immunohistochemical staining of formalin-fixed, paraffin-embedded tumor tissue. Patient survival was the clinical end point. The effects of COX-2 expression on cell survival and radioresistance was tested in vitro using the selective COX-2 inhibitor NS-398 in conjunction with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazonium bromide (MTT) and clonogenic assays. Results. COX-2 immunoreactivity was detected in 62% of NPC tumors, and expression levels were high in 43%. Survival analysis showed the 5-year overall survival rates for patients who had high COX-2 expression was 27% compared with 60% for those with low/absent expression (p = .047). Pattern of failure analysis showed no significant difference between high and low COX-2 expression in locoregional failure (27% vs 25%, p = .91). However, patients with N0 to N1 disease and high COX-2 expression had a significantly higher incidence of distant metastasis compared with patients with stage N0 to N1 disease and low COX-2 expression (83% vs 15%, p = .004). This difference was not observed in patients with N2 to N3 disease. This difference contributed to worse survival of patients whose tumors had high COX-2 expression levels. The selective COX-2 inhibitor NS-398 was directly cytotoxic to NPC-BM1 cells in vitro, as judged in an MTT assay (viable cells decreased from 92% to 76%, 52%, and 22%, with increases of NS-398 from 20 to 40, 60, and 80 ,M, respectively). Radiation-induced cell death was also increased by treatment with NS-398. At a 10% survival level, 40 ,M NS-398 increased radiation cytotoxicity by a factor of 1.37, whereas 60 ,M increased it by a factor of 4.9. Conclusions. COX-2 overexpression is a predictor for poor survival for advanced stage NPC. In vitro, NS-398 radiosensitizes the NPC-BM1 cell line, providing a basis for testing the combination of COX-2 inhibitors with radiation in the treatment of patients with NPC. © 2005 Wiley Periodicals, Inc. Head Neck27: XXX,XXX, 2005 [source]


    Long-term outcomes of positive fluorescence in situ hybridization tests in primary sclerosing cholangitis,

    HEPATOLOGY, Issue 1 2010
    Sanjay Y. Bangarulingam
    Patients with primary sclerosing cholangitis (PSC) are at increased risk for developing cholangiocarcinoma (CCA). Fluorescence in situ hybridization (FISH) is a cytological test designed to enhance early CCA diagnosis. The long-term outcome of PSC patients with a positive FISH test (polysomy, trisomy/tetrasomy) are unclear. All PSC patients with at least one FISH test were identified and defined to have CCA if they had a positive tissue biopsy, positive cytology, or evidence of cancer in the explant after liver transplantation. A total of 235 PSC patients had at least one FISH test performed, and 56 patients had CCA on histopathology (n = 35) or cytology (n = 21). Overall, 120 of 235 (51%) of PSC patients tested for FISH were positive, but only one third of these positive patients had CCA. Sensitivity and specificity for FISH polysomy were 46% and 88%, and for trisomy/tetrasomy they were 25% and 67%, respectively. Survival analysis showed that patients with FISH polysomy had an outcome similar to patients with CCA; whereas FISH trisomy/tetrasomy patients had an outcome similar to patients with negative FISH tests. The FISH polysomy patients without cancer compared with those with CCA had lower serum bilirubin, lower carbohydrate antigen 19-9 (CA 19-9), lower Mayo risk score, and lower occurrence of dominant strictures. Conclusion: In PSC patients, the presence of a dominant stricture plus FISH polysomy has a specificity of 88% for CCA. Patients with FISH showing trisomy or tetrasomy have a similar outcome to patients with negative FISH. FISH testing should be used selectively in patients with other signs indicating CCA and not as a screening tool in all PSC patients undergoing endoscopic retrograde cholangiopancreatography (ERCP). (HEPATOLOGY 2009.) [source]


    Prognostic value of p27kip1 expression in adenocarcinoma of the pancreatic head region

    HPB, Issue 3 2006
    Jerzy Mielko
    Abstract Background. p27kip1 is a tumour suppressor gene, functioning as a cyclin-dependent kinase inhibitor, and an independent prognostic factor in breast, colon, and prostate adenocarcinomas. Conflicting data are reported for adenocarcinoma of the pancreas. The aim of this study was to establish the prognostic value of p27kip1 expression in adenocarcinoma of the pancreatic head region. Patients and methods. The study included 45 patients (male/female ratio 2:1; mean age 59, range 38,82 years) with adenocarcinomas of the pancreatic head region: 24 , pancreatic head, 18 , periampullary and 3 , uncinate process. The patients underwent the Kausch-Whipple pancreatoduodenectomy (n=39), pylorus-preserving pancreatoduodenectomy (n=5), or nearly total pancreatectomy (n=1). Eight patients received adjuvant chemotherapy postoperatively. Follow-up time ranged from 3 to 60 months. Tumours were staged according to the pTNM classification (UICC 1997). Immunohistochemistry was done on paraffin-embedded blocks from tumour sections. Quantitative determination of p27kip1 expression was based on the proportion of p27kip1 -positive cells (< 5%= negative). Survival analysis was carried out using the Kaplan-Meier method and Cox regression model. Results. Positive p27kip1 expression was detected in 22 tumours (49%), whereas 23 tumours (51%) were p27kip1 -negative. There were no significant correlations between p27kip1 index and stage or lymph node involvement. Median survival time in patients with p27kip1 -positive tumours was 19 months, whereas in patients with p27kip1 -negative tumours it was 18 months (p=0.53). A significant relationship was found between p27kip1 -negative tumours and radical resection (p=0.04). Multivariate survival analysis revealed that the localization of the tumour (pancreatic head/uncinate process vs periampullary) was the only significant and independent prognosticator (p=0.01, Cox regression model). Resection margins involvement and grade remained nearly significant prognostic factors (p=0.07 and p=0.09, respectively). Conclusion. We conclude that p27kip1 has limited overall prognostic utility in resected carcinoma of the pancreatic head region, but its potential role as a marker of residual disease needs to be further assessed. [source]


    Survival analysis of Little Penguin Eudyptula minor chicks on Motuara Island, New Zealand

    IBIS, Issue 4 2001
    MARTIN RENNER
    Chick survival of Little Penguins Eudyptula minor was studied on predator-free Motuara Island, Cook Strait, New Zealand (41d,05'S, 174d,15'E), in 1995 and 1996. We used the Kaplan-Meier estimator and robust Cox regression to estimate chick survival rate (pL se) at 0.325 pL 0.044, leading to an estimated survival from laying to fledging of 0.13 or a reproductive output of 0.26 chicks per pair and breeding attempt. Starvation posed the greatest mortality risk, followed by unknown factors and rain. Risk of death due to rain was restricted to the guard stage, whereas starvation occurred throughout the nesting period, though with a peak in the early guard stage. Significant seasonal differences in survival rate were detected in both years, but with reversed trends, survival decreasing with the season in 1995 and increasing in 1996. Failure of adults to relieve their partner on the nest after chicks hatched accounted for 16% mortality or 34% of all chick deaths. Differences in chick survival rate between nest types were significant in 1995, a year with high rainfall, but not in 1996. Nests in the base of hollow trees had the highest chick survival rate. Of chicks in open nests - a nest type that is unusual for this species - 5.4% fledged. Our results suggest that on Motuara Island good breeding sites are scarce and that the food supply has been poor during the years of this study. [source]