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PubMed1984

The longest illness. Effects of nuclear war in children.

The destruction of civilization that would follow a nuclear war would render any disaster ever recorded insignificant. Millions of people would perish during the first few hours, and many more would die in the months to come. Survival would exist only in the strictest sense of the word, since societal disorganization, famine, drought, darkness, and nuclear winter would envelope the earth. The comparative frailty of children and their dependence on adults would render them most susceptible to the acute effects of a nuclear holocaust. Furthermore, studies of the Hiroshima and Nagasaki, Japan bombings showed a disproportionate propensity for children to experience leukemias and other cancers years after the bombings. There were also great increases in perinatal deaths and cases of microcephaly and retardation in children exposed in utero to the bombs. In the event that there are future generations after a nuclear war, the issue of heritable genetic effects will become important. Suggestions of permanent genetic damage are emerging from the Hiroshima and Nagasaki studies. By comparison, the genetic effects of modern weaponry will be incalculable.

Blast Injuries↗

PubMed2003

Mild depressive symptoms are associated with amplified and prolonged inflammatory responses after influenza virus vaccination in older adults.

BACKGROUND: Depression is associated with enhanced production of proinflammatory cytokines that influence a spectrum of conditions associated with aging, including cardiovascular disease, osteoporosis, arthritis, type 2 diabetes mellitus, certain cancers, periodontal disease, frailty, and functional decline. In this prospective community study, we assessed the relationship between depressive symptoms and changes in inflammatory response after an influenza virus vaccination. METHODS: To study the dynamics of interleukin (IL) 6 levels in plasma in response to an immunological challenge, we obtained blood samples in 119 older adults (mean age, 71.21 +/- 8.68 years [SD]) immediately before an annual influenza vaccination and again 2 weeks later. The short form of the Beck Depression Inventory, completed at these same times, provided information on depressive symptoms. RESULTS: The number of depressive symptoms in this sample was low on average before vaccination (mean +/- SD number of symptoms, 3.07 +/- 3.09) and did not change significantly after vaccination. Participants with more depressive symptoms had higher levels of IL-6 before and after vaccination than did those who reported fewer symptoms; moreover, individuals reporting more depressive symptoms also showed an increase in plasma IL-6 levels 2 weeks later, while there was little change in IL-6 levels among those reporting few or no symptoms. CONCLUSIONS: Even a modest number of depressive symptoms may sensitize the inflammatory response system in older adults and produce amplified and prolonged inflammatory responses after infection and other immunological challenges. Sustained and/or amplified inflammatory responses could accelerate a range of age-related diseases.

Age Factors↗

PubMed1998

Risk factors for 5-year mortality in older adults: the Cardiovascular Health Study.

CONTEXT: Multiple factors contribute to mortality in older adults, but the extent to which subclinical disease and other factors contribute independently to mortality risk is not known. OBJECTIVE: To determine the disease, functional, and personal characteristics that jointly predict mortality in community-dwelling men and women aged 65 years or older. DESIGN: Prospective population-based cohort study with 5 years of follow-up and a validation cohort of African Americans with 4.25-year follow-up. SETTING: Four US communities. PARTICIPANTS: A total of 5201 and 685 men and women aged 65 years or older in the original and African American cohorts, respectively. MAIN OUTCOME MEASURES: Five-year mortality. RESULTS: In the main cohort, 646 deaths (12%) occurred within 5 years. Using Cox proportional hazards models, 20 characteristics (of 78 assessed) were each significantly (P<.05) and independently associated with mortality: increasing age, male sex, income less than $50000 per year, low weight, lack of moderate or vigorous exercise, smoking for more than 50 pack-years, high brachial (>169 mm Hg) and low tibial (< or = 127 mm Hg) systolic blood pressure, diuretic use by those without hypertension or congestive heart failure, elevated fasting glucose level (>7.2 mmol/L [130 mg/dL]), low albumin level (< or = 37 g/L), elevated creatinine level (> or = 106 micromol/L [1.2 mg/dL]), low forced vital capacity (< or = 2.06 mL), aortic stenosis (moderate or severe) and abnormal left ventricular ejection fraction (by echocardiography), major electrocardiographic abnormality, stenosis of internal carotid artery (by ultrasound), congestive heart failure, difficulty in any instrumental activity of daily living, and low cognitive function by Digit Symbol Substitution test score. Neither high-density lipoprotein cholesterol nor low-density lipoprotein cholesterol was associated with mortality. After adjustment for other factors, the association between age and mortality diminished, but the reduction in mortality with female sex persisted. Finally, the risk of mortality was validated in the second cohort; quintiles of risk ranged from 2% to 39% and 0% to 26% for the 2 cohorts. CONCLUSIONS: Objective measures of subclinical disease and disease severity were independent and joint predictors of 5-year mortality in older adults, along with male sex, relative poverty, physical activity, smoking, indicators of frailty, and disability. Except for history of congestive heart failure, objective, quantitative measures of disease were better predictors of mortality than was clinical history of disease.

Black or African American↗

PubMed2001

Perspectives on care at the close of life. Serving patients who may die soon and their families: the role of hospice and other services.

The case story of a 47-year-old man with advanced rectal carcinoma illustrates the professional services and care system strategies available to help clinicians serve patients coming to the end of life. For this patient, who understands his prognosis, primary care physician services include (1) prevention and relief of symptoms, (2) assessment of each treatment before and during implementation, (3) ensuring that the patient designates a surrogate decision-maker and makes advance plans, and (4) preparation of patient and family for the time near death. Good care may entail enduring unavoidably difficult times with patients and their families. Enrollment in a hospice program requires that decision-makers confront the prognosis and their uncertainties about it, consider the desirability of other services, recognize variations among available hospice programs, address financial issues, and weigh the distress of patients and loved ones at being labeled as "dying." Hospice provides competent, continuous, and reasonably comprehensive care, but it has some constraints. Function and symptoms for those living with serious chronic illness at the end of life generally follow 1 of 3 trajectories: (a) a short period of obvious decline at the end, which is typical of cancer; (b) long-term disability, with periodic exacerbations, and unpredictable timing of death, which characterizes dying with chronic organ system failures; or (c) self-care deficits and a slowly dwindling course to death, which usually results from frailty or dementia. Effective and reliable care for persons coming to the end of life will require changes in the organization and financing of care to match these trajectories, as well as compassionate and skillful clinicians.

Advance Care Planning↗

PubMed2001

Bone mineral density response to estrogen replacement in frail elderly women: a randomized controlled trial.

CONTEXT: Although hormone replacement therapy (HRT) is an established approach for osteoporosis prevention, little is known about the osteoprotective effects of HRT in frail elderly women. OBJECTIVE: To determine whether HRT increases bone mineral density (BMD) in frail elderly women. DESIGN AND SETTING: Randomized, double-blind, placebo-controlled trial conducted in a US university-based research center from September 1995 to August 2000. PARTICIPANTS: Sixty-seven women aged 75 years or older with mild-to-moderate physical frailty. INTERVENTION: Participants were randomly assigned to receive conjugated estrogens, 0.625 mg/d, plus trimonthly medroxyprogesterone acetate, 5 mg/d for 13 days (n = 45), or matching placebo (n = 22), for 9 months. MAIN OUTCOME MEASURES: The primary outcome measure was 9-month change in BMD of the lumbar spine and hip, measured by dual-energy x-ray absorptiometry. Secondary outcomes were changes in markers of bone turnover. RESULTS: Based on intention-to-treat analyses, HRT resulted in significantly larger increases in BMD of the lumbar spine than placebo (mean change, 4.3% vs 0.4%; between-group difference, 3.9%; 95% confidence interval [CI], 3.5%-4.3%) and total hip (mean change, 1.7% vs -0.1%; between-group difference, 1.8%; 95% CI, 1.5%-2.1%). Compared with placebo, HRT resulted in significant decreases in serum bone-specific alkaline phosphatase levels (mean change, -24% vs 6%; between-group difference, -30%; 95% CI, -26% to -33%) and urine N-telopeptide levels (mean change, -48% vs 4%; between-group difference, -52%; 95% CI, -47% to -55%). CONCLUSIONS: In physically frail elderly women, 9 months of HRT significantly increased BMD compared with placebo in clinically important skeletal regions. Further studies are needed to determine whether these osteogenic effects of HRT in elderly women are associated with a reduction in osteoporotic fractures.

Absorptiometry, Photon↗

PubMed2003

Patterns of functional decline at the end of life.

CONTEXT: Clinicians have observed various patterns of functional decline at the end of life, but few empirical data have tested these patterns in large populations. OBJECTIVE: To determine if functional decline differs among 4 types of illness trajectories: sudden death, cancer death, death from organ failure, and frailty. DESIGN, SETTING, AND PARTICIPANTS: Cohort analysis of data from 4 US regions in the prospective, longitudinal Established Populations for Epidemiologic Studies of the Elderly (EPESE) study. Of the 14 456 participants aged 65 years or older who provided interviews at baseline (1981-1987), 4871 died during the first 6 years of follow-up; 4190 (86%) of these provided interviews within 1 year before dying. These decedents were evenly distributed in 12 cohorts based on the number of months between the final interview and death. MAIN OUTCOME MEASURES: Self- or proxy-reported physical function (performance of 7 activities of daily living [ADLs]) within 1 year prior to death; predicted ADL dependency prior to death. RESULTS: Mean function declined across the 12 cohorts, simulating individual decline in the final year of life. Sudden death decedents were highly functional even in the last month before death (mean [95% confidence interval [CI]] numbers of ADL dependencies: 0.69 [0.19-1.19] at 12 months before death vs 1.22 [0.59-1.85] at the final month of life, P =.20); cancer decedents were highly functional early in their final year but markedly more disabled 3 months prior to death (0.77 [0.30-1.24] vs 4.09 [3.37-4.81], P<.001); organ failure decedents experienced a fluctuating pattern of decline, with substantially poorer function during the last 3 months before death (2.10 [1.49-2.70] vs 3.66 [2.94-4.38], P<.001); and frail decedents were relatively more disabled in the final year and especially dependent during the last month (2.92 [2.24-3.60] vs 5.84 [5.33-6.35], P<.001). After controlling for age, sex, race, education, marital status, interval between final interview and death, and other demographic differences, frail decedents were more than 8 times more likely than sudden death decedents to be ADL dependent (OR, 8.32 [95% CI, 6.46-10.73); cancer decedents, one and a half times more likely (OR, 1.57 [95% CI, 1.25-1.96]); and organ failure decedents, 3 times more likely (OR, 3.00 [95% CI, 2.39-3.77]). CONCLUSIONS: Trajectories of functional decline at the end of life are quite variable. Differentiating among expected trajectories and related needs would help shape tailored strategies and better programs of care prior to death.

Activities of Daily Living↗

PubMed2003

Exercise plus behavioral management in patients with Alzheimer disease: a randomized controlled trial.

CONTEXT: Exercise training for patients with Alzheimer disease combined with teaching caregivers how to manage behavioral problems may help decrease the frailty and behavioral impairment that are often prevalent in patients with Alzheimer disease. OBJECTIVE: To determine whether a home-based exercise program combined with caregiver training in behavioral management techniques would reduce functional dependence and delay institutionalization among patients with Alzheimer disease. DESIGN, SETTING, AND PATIENTS: Randomized controlled trial of 153 community-dwelling patients meeting National Institute of Neurological and Communicative Diseases and Stroke/Alzheimer Disease and Related Disorders Association criteria for Alzheimer disease, conducted between June 1994 and April 1999. INTERVENTIONS: Patient-caregiver dyads were randomly assigned to the combined exercise and caregiver training program, Reducing Disability in Alzheimer Disease (RDAD), or to routine medical care (RMC). The RDAD program was conducted in the patients' home over 3 months. MAIN OUTCOME MEASURES: Physical health and function (36-item Short-Form Health Survey's [SF-36] physical functioning and physical role functioning subscales and Sickness Impact Profile's Mobility subscale), and affective status (Hamilton Depression Rating Scale and Cornell Depression Scale for Depression in Dementia). RESULTS: At 3 months, in comparison with the routine care patients, more patients in the RDAD group exercised at least 60 min/wk (odds ratio [OR], 2.82; 95% confidence interval [CI], 1.25-6.39; P =.01) and had fewer days of restricted activity (OR, 3.10; 95% CI, 1.08-8.95; P<.001). Patients in the RDAD group also had improved scores for physical role functioning compared with worse scores for patients in the RMC group (mean difference, 19.29; 95% CI, 8.75-29.83; P<.001). Patients in the RDAD group had improved Cornell Depression Scale for Depression in Dementia scores while the patients in the RMC group had worse scores (mean difference, -1.03; 95% CI, -0.17 to -1.91; P =.02). At 2 years, the RDAD patients continued to have better physical role functioning scores than the RMC patients (mean difference, 10.89; 95% CI, 3.62-18.16; P =.003) and showed a trend (19% vs 50%) for less institutionalization due to behavioral disturbance. For patients with higher depression scores at baseline, those in the RDAD group improved significantly more at 3 months on the Hamilton Depression Rating Scale (mean difference, 2.21; 95% CI, 0.22-4.20; P =.04) and maintained that improvement at 24 months (mean difference, 2.14; 95% CI, 0.14-4.17; P =.04). CONCLUSION: Exercise training combined with teaching caregivers behavioral management techniques improved physical health and depression in patients with Alzheimer disease.

Activities of Daily Living↗

PubMed2004

Recovery from disability among community-dwelling older persons.

CONTEXT: Previous studies have found that a sizeable minority of newly disabled older persons recover independent function; however, long intervals between assessments have led to difficulty in determining the true incidence and duration of disability, and therefore in accurately characterizing the probability and course of recovery. OBJECTIVES: To determine the rate of and time to recovery of independent function in community-dwelling older persons who become newly disabled in their activities of daily living (ADLs), to determine the duration of recovery, and to compare the likelihood of recovery among pertinent subgroups of older persons. DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort study, with monthly assessments of ADL function, for 754 initially nondisabled, community-dwelling persons aged 70 years or older, performed in a small urban area from March 1998 to May 2003. MAIN OUTCOME MEASURES: Demographic features, chronic conditions, cognitive function, and physical frailty were determined during comprehensive assessments at 18-month intervals. Disability, defined as needing personal assistance with 1 or more key ADLs (bathing, dressing, walking, and transferring), was assessed during monthly telephone interviews. RESULTS: A total of 420 participants (56%) experienced disability during a median follow-up of 51 months. Of these participants, 399 (81%) recovered (ie, regained independence in all 4 ADLs) within 12 months of their initial disability episode, and a majority (57%) of these maintained independence for at least 6 months. Among participants who experienced 3 or more consecutive months of disability, a majority (60%) recovered, but only a third of these maintained independence for at least 6 months. Persons who were cognitively impaired, physically frail, or severely disabled (ie, in 3-4 ADLs) at onset were less likely to recover than those who were cognitively intact, nonfrail, or mildly disabled, respectively. Nonetheless, a majority of participants within each subgroup recovered. CONCLUSIONS: Newly disabled older persons recover independent ADL function at rates far exceeding those that have been previously reported. Recovery from disability, however, is often short-lasting, suggesting that additional efforts are warranted to maintain independence in this high-risk group.

Activities of Daily Living↗

PubMed1999

Two-state mixed renewal processes for chronic disease.

We develop a model based on a two-state mixed renewal process and propose its use for modelling disease activity in studies of chronic conditions. We specify Weibull forms for the conditional transition intensities to allow for time trends, and bivariate frailties to accommodate subject-to-subject variability in the disease process. Extensions of this model are considered for stratified analyses in which strata are defined by the number of past exacerbations. Data from a motivating study of chronic bronchitis are analysed to illustrate the methodology.

Anti-Infective Agents↗

PubMed1999

Testing for centre effects in multi-centre survival studies: a Monte Carlo comparison of fixed and random effects tests.

The problem of testing for a centre effect in multi-centre studies following a proportional hazards regression analysis is considered. Two approaches to the problem can be used. One fits a proportional hazards model with a fixed covariate included for each centre (except one). The need for a centre specific adjustment is evaluated using either a score, Wald or likelihood ratio test of the hypothesis that all the centre specific effects are equal to zero. An alternative approach is to introduce a random effect or frailty for each centre into the model. Recently, Commenges and Andersen have proposed a score test for this random effects model. By a Monte Carlo study we compare the performance of these two approaches when either the fixed or random effects model holds true. The study shows that for moderate samples the fixed effects tests have nominal levels much higher than specified, but the random effect test performs as expected under the null hypothesis. Under the alternative hypothesis the random effect test has good power to detect relatively small fixed or random centre effects. Also, if the centre effect is ignored the estimator of the main treatment effect may be quite biased and is inconsistent. The tests are illustrated on a retrospective multi-centre study of recovery from bone marrow transplantation.

Bone Marrow Transplantation↗

PubMed1998

Modeling hazard functions in families.

A genetic frailty model is presented for censored age of onset data in nuclear families where individuals carrying a genetic susceptibility gene have an increased risk of becoming affected. We use maximum likelihood via the EM algorithm to estimate the genetic relative risk and the allele frequency under a dominant susceptibility type and a proportional hazards model. When sampling is from a disease registry, likelihood corrections are necessary for reducing bias in the parameter estimates. In these biased samples, the full conditional likelihood is approximated by a likelihood conditional on the proband's age of onset. For unbiased samples, simulations show the distributions of the estimates are similar under both a semiparametric and the correctly specified parametric likelihoods. For biased samples, simulations under the approximate conditional likelihood show the median estimates of the allele frequency and genetic relative risk tend to under- and overestimate, respectively, the true values; however, the approximation is better for rarer allele frequencies (0.0033 vs. 0.01). In practice, large samples or more complex ascertainment corrections are recommended. Using the approximate conditional likelihood on familial breast cancer onset data collected as part of a case-control study at the Fred Hutchinson Cancer Research Center in Seattle, Washington, we estimate an allele frequency of 0.0009 (approximate 95% CI 0.0006-0.002) and a genetic relative risk of 104 (approximate 95% CI 55-181).

Adolescent↗

PubMedDate not supplied

Cluster modelling of disease incidence via RJMCMC methods: a comparative evaluation. Reversible jump Markov chain Monte Carlo.

The spatial modelling of small area health data has, for some time, included spatial autocorrelation as a random effect. This effect is non-specific and global and does not address the location of clusters of disease (a specific task). This paper addresses the need for specific and non-specific random effects within spatial epidemiology. In addition, individual frailty is also considered important and a computational algorithm based on reversible jump Markov chain Monte Carlo (RJMCMC) methods is described.

Algorithms↗

PubMed2000

Proportional hazards model with random effects.

We propose a general proportional hazards model with random effects for handling clustered survival data. This generalizes the usual frailty model by allowing a multivariate random effect with arbitrary design matrix in the log relative risk, in a way similar to the modelling of random effects in linear, generalized linear and non-linear mixed models. The distribution of the random effects is generally assumed to be multivariate normal, but other (preferably symmetrical) distributions are also possible. Maximum likelihood estimates of the regression parameters, the variance components and the baseline hazard function are obtained via the EM algorithm. The E-step of the algorithm involves computation of the conditional expectations of functions of the random effects, for which we use Markov chain Monte Carlo (MCMC) methods. Approximate variances of the estimates are computed by Louis' formula, and posterior expectations and variances of the individual random effects can be obtained as a by-product of the estimation. The inference procedure is exemplified on two data sets.

Algorithms↗

PubMed2000

A continuation ratio random effects model for repeated ordinal responses.

This paper presents methods of analysis for ordinal repeated measures. We use a generalization of the continuation ratio model with a random effect. We handle frailty by using a normal distribution and also a non-parametric distribution. The methodology is readily implemented in existing software and flexible enough to treat large data sets with uncommon time measurements as well as different numbers of repeated measures for each individual. The models are used to investigate how a group of explanatory variables influences the overall condition of patients treated for breast cancer.

Age Factors↗

PubMed2003

Electroconvulsive therapy for the depressed elderly.

BACKGROUND: Depressive disorder is a common mental disorder in old age, with serious health consequences such as increased morbidity, disability, and mortality. The frailty of elderly may seriously hamper the efficacy and safety of pharmacotherapy in depressed elderly. Electroconvulsive therapy (ECT) in depressed elderly therefore may be an alternative to treatment with antidepressants. OBJECTIVES: To assess the efficacy and safety of ECT (compared to simulated ECT or antidepressants) in depressed elderly. SEARCH STRATEGY: We searched the CCDANCTR database, Medline 1966-2000, EMBase 1980-2000, Biological abstracts 1985-2000, Cinahl 1982-2000, Lilacs from 1982 onwards, Psyclit 1887-2000, Sigle 1980-2000. The reference lists of relevant papers were scanned for published reports. Hand searching of the Journal of ECT and the Journal of Geriatric Psychiatry was done. Based on the title of the publication and its abstract, non-eligible citations were excluded. SELECTION CRITERIA: Data were independently extracted by at least two reviewers. Randomised, controlled trials on depressed elderly (> 60 years) with or without concomitant with conditions like cerebrovascular disease, dementia of the Alzheimer's type, vascular dementia or Parkinson's disease were included. DATA COLLECTION AND ANALYSIS: Data were independently extracted by at least two reviewers. For continuous data weighted mean differences (WMD) between groups were calculated. MAIN RESULTS: Randomised evidence is sparse. Only three trials could be included, one on the efficacy of real ECT versus simulated ECT (O'Leary et al 1994), one on the efficacy of unilateral versus bilateral ECT (Fraser 1980) and the other comparing the efficacy of ECT once a week with ECT three times weekly (Kellner 1992). All had major methodological shortcomings; data were mostly lacking essential information to perform a quantitative analysis. Although the O'Leary study concluded that real ECT was superior over simulated ECT, these conclusions need to be interpreted cautiously. Only results from the second trial (unilateral versus bilateral ECT) could be analysed, not convincingly showing efficacy of unilateral ECT over bilateral ECT, WMD 6.06 (CI -5.20,17.32). Randomised evidence on the efficacy and safety of ECT in depressed elderly with concomitant dementia, cerebrovascular disorders or Parkinson's disease is completely lacking. Possible side-effects could not be adequately examined because the lack of randomised evidence and the methodological shortcomings. REVIEWER'S CONCLUSIONS: None of the objectives of this review could be adequately tested because of the lack of firm, randomised evidence. Given the specific problems in the treatment of depressed elderly, it is of importance to conduct a well designed randomised controlled trial in which the efficacy of ECT is compared to one or more antidepressants.

Aged↗

PubMedDate not supplied

Biological aging and Cox hazard analysis of mortality trends in a Mennonite community from south-central Kansas.

This study investigated mortality in 568 individuals from the Goessel Mennonite community in rural central Kansas. There were three main objectives to this research: 1) characterize mortality trends within a biologically well-defined Mennonite community; 2) determine what biochemical, morphological, and physiological risk factors could be related to all-cause mortality, stratified by age and sex; and 3) compare these results to previously described variables that were associated with both biological age and mortality in this population. Mortality data were obtained from three sources: Kansas Vital Records, the Social Security death index, and church records. In total, 221 (39%) individuals were found to have died in this population between January 1980-June 2002. Analogous to the larger US population, the three leading causes of death in this community were heart disease, cancer, and stroke, accounting for 60% of all deaths. Besides advancing age, the greatest biological risk factor in this population was decreased amounts of albumin in men (relative risk, 2.47), potentially indicating underreported cases of either chronic kidney disease or frailty syndrome for males. Cox proportional hazard models demonstrated that increased amounts of total cholesterol may provide a protective effect for elderly individuals. We conclude, based on the previously described heritability of both albumin (h(2) = 0.40) and total cholesterol (h(2) = 0.50) in this population, that underlying genetic factors associated with both chronic degenerative diseases and biological aging may have important implications for understanding mortality patterns in this community.

Aged↗

PubMed1996

Human senescence.

Human life expectancy has increased dramatically through improvements in public health, housing, nutrition and general living standards. Lifespan is now limited chiefly by intrinsic senescence and its associated frailty and diseases. Understanding the biological basis of the ageing process is a major scientific challenge that will require integration of molecular, cellular, genetic and physiological approaches. This article reviews progress that has been made to date, particularly with regard to the genetic contribution to senescence and longevity, and assesses the scale of the task that remains.

Aging↗

PubMed2005

Testing homogeneity in Weibull-regression models.

In survival studies with families or geographical units it may be of interest testing whether such groups are homogeneous for given explanatory variables. In this paper we consider score type tests for group homogeneity based on a mixing model in which the group effect is modelled as a random variable. As opposed to hazard-based frailty models, this model presents survival times that conditioned on the random effect, has an accelerated failure time representation. The test statistics requires only estimation of the conventional regression model without the random effect and does not require specifying the distribution of the random effect. The tests are derived for a Weibull regression model and in the uncensored situation, a closed form is obtained for the test statistic. A simulation study is used for comparing the power of the tests. The proposed tests are applied to real data sets with censored data.

Animals↗