Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Length Of Life”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 199 records · Page 11Linked to original sources
PubMed1992

The standardized mortality ratio and life expectancy.

This paper develops a theoretical relation between the standardized mortality ratio (SMR) and the expected years of life and establishes a regression equation for easy conversion between these two statistics. The mathematical expression of the derived relation is an approximation, requiring an assumption of constant age-specific mortality ratios. It underestimates the "true" value calculated based on life table technique when the age-specific mortality ratios increase with age. This equation provides a conservative method to estimate the expected years of life for cohort mortality studies and facilitates an assessment of the impact of work-related factors on the length of life of the worker. It also allows one to convert the SMR to life expectancy in smaller studies whose sole objective is to determine the SMR in a working population. A 1% decrease (or increase) in the standardized mortality ratio will result in 0.1373 years increased (or decreased) life expectancy based on white male data for the US population. Furthermore, with data from 14 large oil refinery and chemical worker cohorts of white males, the "derived" expected years of life based on the regression equation closely predicts the corresponding value calculated using a standard life table technique. This statistical equation is expected to have practical applications when used in conjunction with the SMR to provide an approximate measure of life expectancy, a term and statistic familiar to most lay people.

Adult↗
PubMed1998

Use of linear type and production data to supplement early predicted transmitting abilities for productive life.

Genetic evaluations for the length of productive life based on actual DHIA culling data have been available in the US since January 1994. Although substantial genetic variation in productive life exists, the reliability of selection is often low, particularly for recently progeny-tested bulls having daughters that have not yet had an opportunity to be culled. Correlated production and conformation traits, which have higher heritability than productive life and are available earlier in life, may be used to enhance evaluations of productive life for young bulls that have little or no direct culling information available. Genetic correlations between productive life and milk, fat, dairy form, and udder traits ranged from +0.22 to +0.46. The maximum reliability of the indirect prediction of productive life from 16 correlated type and production traits was 0.56, and the maximum reliability from a subset of 10 traits was 0.51. Indirect information about productive life that was derived from type and production traits was combined with actual culling information to increase the total amount of available information for many recently progeny-tested bulls. The procedures described herein for enhancing direct evaluations for the productive life of dairy sires with indirect information about production and type were implemented by the USDA Animal Improvement Programs Laboratory and the Holstein Association USA in July 1994.

Animals↗
PubMed2001

Death at home following a targeted advance-care planning process at home: the kitchen table discussion.

OBJECTIVE: To determine whether home health agency patients' preferences to die at home can be honored following a structured, professionally facilitated advance-care planning (ACP) process provided in the home. DESIGN: A case series of patients who were identified by their home health agency nurses as having a life-limiting illness and then referred for social service assessment, followed for at least 6 months, with median follow-up of 191 days. SETTING: A large, urban, home health agency owned by a not-for-profit integrated healthcare system. PARTICIPANTS: Eighty-four adult patients (median age 75, range 37-94) receiving home care services other than hospice. INTERVENTION: Formally structured social work visits at patients' homes to discuss end-of-life issues, with communication of results to home health nurses and attending physicians. Social workers performed standard psychosocial assessments, obtained patient and family preferences regarding end-of-life care, and provided education about hospice services. MEASUREMENTS: Acceptance of the ACP process, preferences for location of end-of-life care, location of care at the end of life, adequacy of timing of intervention as measured by length of life after ACP, and use of hospice services. RESULTS: Eighty-three of 84 participants (99%) were willing to complete an ACP process in the home setting. Of the 54 patients expressing a clear preference for location of end-of-life care, 46 (82%) wanted this care to be at home. Thirty-nine (46%) of the participants died within 90 days of ACP; 58 (69%) died by the end of the study. Forty-three (75%) of these deaths occurred at home or in a hospice residence. Fifty-one (61%) patients used home, residential, or nursing home-based hospice services during the study. CONCLUSION: In this series of seriously ill home health patients, most preferred to die at home and virtually all were willing to participate in a home-based ACP process. Facilitating ACP among such patients and their families was associated with end-of-life care at home. Use of hospice services was common following ACP in this population.

Adult↗
PubMed1983

Temporal and compositional dietary restrictions modulate age-related changes in serum lipids.

Life-lon restriction of food, which markedly increases the length of life of rats, also delays the occurrence of age-related physiological deteriorations including the age-related changes in serum lipids. The aim of this study was to explore the effects of 1) food restriction limited to early life, 2) food restriction initiated in adult life and 3) restriction of protein without restriction of calories on the age-related changes in serum lipids. Food restriction started at 6 months of age was as effective as food restriction started at 6 weeks of age in modulating the age-related changes in serum lipids, whereas food restriction from 6 weeks to 6 months of age and restriction of protein but not calories were much less effective. Changes in the rate of very low density lipoprotein-triglyceride removal from the blood were not responsible for the age-related increase in triglyceride concentration or for the modulation of this increase by the dietary regimens. Age-related changes in serum or plasma levels of glucose, ketone bodies, insulin and glucagon were also measured and the modulating effects of the dietary regimens studied; possible relationships between the concentrations of these substances and the concentrations of the serum lipids are discussed.

Aging↗
PubMed1988

Effects of age, sex, and post mortem interval on intestinal lengths of horses during development.

Lengths of small intestine, caecum, ascending colon and descending colon were measured in intestinal tracts from 103 foetuses, foals and adult horses. Intestinal tracts from 21 of the horses were measured at varying intervals after death. Total intestinal length increased markedly from mid-gestation to one year of age, then showed little increment up to 35 years. Small intestinal length increased most rapidly in the first month of life. Caecal length increased most rapidly from one to six months and length of ascending colon increased most rapidly between one week and one year. Descending colon length increased gradually after birth. Periods of rapid increase in length of various intestinal segments and alterations in the percentage of total intestinal length were associated with periods of rapid body growth and changes in dietary composition. Sex and post mortem interval did not affect intestinal length significantly.

Animals↗
PubMed2001

Non-secreting pituitary tumors in adolescents--consequences in adulthood.

This article reviews non-secreting pituitary tumors in children and adolescents. These tumors include a wide range of pathological situations. They differ from those in adults regarding incidence, pathology, clinical presentation, size and consequences. Pituitary tumors are uncommon in this age group (2.7% of intracranial tumors) whilst in adults they represent 22.5-27%. Pituitary adenomas are the most frequent in adults (30%) while craniopharyngiomas are more common in children and adolescents (80-90%). Of pituitary adenomas in children and adolescents, non-secreting pituitary adenomas are very rare (3-6%) and are usually macroadenomas. These are usually benign, not life threatening, but can profoundly affect the quality and length of life because of serious secondary complications. In spite of the difficulties presented, surgery is the treatment of choice for most of these tumors. Even following the best of treatment, however, there is a great possibility of permanent pituitary insufficiency. In a large percentage of patients, these adverse effects of the tumors can be prevented by early and rapid intervention and treatment.

Adolescent↗
PubMed1994

A guide for surveillance of patients with Barrett's esophagus.

OBJECTIVE: Barrett's esophagus (columnar metaplasia of the distal esophagus due to chronic gastroesophageal reflux) affects nearly 700,000 people in the United States, and carries a risk of esophageal adenocarcinoma that is 30-125 times that of an age-matched population. Patients who develop high grade dysplasia are at greatest risk. Current recommendations are for endoscopic surveillance to detect dysplasia and to diagnose carcinoma while it is in an early and possibly treatable stage. In addition, some authorities recommend esophagectomy for high grade dysplasia, whereas others reserve esophagectomy only for those with cancer. There are no controlled trials demonstrating that surveillance increases life expectancy in patients with Barrett's esophagus. Furthermore, endoscopic surveillance of this large group with Barrett's esophagus may be costly, and associated with considerable morbidity. Therefore, our objective was to assess the effectiveness and cost-effectiveness of endoscopic surveillance in patients with Barrett's esophagus. METHODS: Design--Decision analysis using a computer cohort simulation (Markov). We examined 12 strategies: (A) no endoscopic surveillance. Esophagectomy is performed only if cancer is detected by biopsy. (B) no surveillance. Esophagectomy is performed if high grade dysplasia is detected by biopsy: (C1-C5) surveillance at intervals from 1 to 5 yr, with esophagectomy if cancer is diagnosed, and (D1-D5) surveillance at intervals from 1 to 5 yr with esophagectomy if high grade dysplasia is diagnosed. We measured life expectancy, quality-adjusted life expectancy, and incremental cost-effectiveness ratios for each strategy. Data Sources--Medline Search and bibliographies of retrieved articles; expert opinion when published data were not available. RESULTS AND CONCLUSIONS: Annual surveillance with esophagectomy for high grade dysplasia prevents cancer and is the preferred strategy, if only length of life (life expectancy) is considered. For those who consider both length and quality of life, endoscopy every 2-3 yr will provide the greatest quality-adjusted life expectancy. When costs are considered, endoscopy every 5 yr also increases life expectancy and has an incremental cost-effectiveness ratio similar to common medical practices. The cumulative incidence of cancer and the quality of life with an esophagectomy had the greatest impact on the decision for surveillance and the optimal surveillance strategy.

Adenocarcinoma↗
PubMed1990

Assessment of nutritional components in prolongation of life and health by diet.

Restricting the food intake of rodents extends the median length of life and the maximum life-span. It also retards most age-associated physiologic change and age-associated diseases. Our research indicates that the ability to retard disease processes is not the major reason for the extension of life-span or for the retardation of age change in most physiologic systems. Rather, it appears that most of the actions of food restriction are due to its ability to slow the primary aging processes. We found this action to relate to the restriction of calories rather than specific nutrients (e.g., protein or fat or minerals). Our findings point to the reduction in caloric intake per rat rather than per gram lean body mass as the basis of the retardation of aging processes by food restriction. The challenge is to learn how caloric intake per rat is coupled to the aging processes. We are currently focusing on the possibility that neural and endocrine mechanisms are involved. Our preliminary findings point to the likelihood of an involvement of the insulin-glucose system.

Animals↗
PubMedDate not supplied

How long can we live?

The continuing rapid age shift in recent years from predominately a younger to an older population in America and many other countries is a problem of great concern. Its socioeconomic implications for the distant future are quite unpredictable due to our inability to answer a few basic questions. How long will life expectancy continue to increase? What is the maximum possible length of life?

Aging↗
PubMed2005

Should people die a natural death?

In the article the concept of natural death as used in end-of-life decision contexts is explored. Reviewing some recent empirical studies on end-of-life decision-making, it is argued that the concept of natural death should not be used as an action-guiding concept in end-of-life decisions both for being too imprecise and descriptively open in its current use but mainly since it appears to be superfluous to the kind of considerations that are really at stake in these situations. Considerations in terms of the quality of life cost of the intervention in relation to the quality and length of life benefits of the same intervention. In referring to the concept of natural death we risk to blur these considerations and end up in difficult distinctions between what is a natural and non- or un-natural death, a distinction which it is argued is of no real moral interest.

Attitude to Death↗
PubMed2005

The momentum of mortality change.

Mortality change is not usually assigned much importance as a source of population growth when future population trends are discussed. Yet it can make a significant contribution to population momentum. In populations that have experienced mortality change, cohort survivorship will continue varying for some time even if period mortality rates become constant. This continuing change in cohort survivorship can create a significant degree of mortality-induced population change, a process we call the 'momentum of mortality change'. The momentum of mortality change can be estimated by taking the ratio of e0 (the period life expectancy at birth) to CAL (the cross-sectional average length of life) for a given year. In industrialized nations, the momentum of mortality change can attenuate the negative effect on population growth of declining fertility or sustained below-replacement fertility. In India, where population momentum has a value of 1.436, the momentum of mortality change is the greatest contributor to its value.

Developed Countries↗
PubMedDate not supplied

Quality of life and related factors among elderly nursing home residents in Southern Taiwan.

This study explored subjectively perceived quality of life and related factors of elderly nursing home residents. In this study, 161 residents aged 65 and older were selected from 10 nursing homes in Southern Taiwan. The results showed: (1) the mean score of quality of life was 15.86 and the standardized score was 52.87, a medium rating for the overall sample; (2) different educational levels, and socioeconomic status were significantly different in the quality of life, the other sociodemographic variables were not significantly different in the quality of life. (3) length of residence in the nursing home was significantly negative relative to the quality of life. Physical function, activities of daily living, social support from nurses, social support from nursing aides, social support from families, and frequency of family interaction were significantly positive relative to the quality of life. (4) Activities of daily living, social support from nurses, socioeconomic status, and physical function were the significant predictors in the quality of life, which explained 40.1% of the total amount of variance. Activities of daily living, social support from nursing aids, socioeconomic status, physical function and frequency of interaction with family were the significant predictors in the quality of life, which explained 39.5% of the total amount of variance. Results generated from this study may act as a reference for the staff of nursing homes to understand the quality of life and related factors among elderly residents. This study also acts as a reference for future intervention programs in this field.

Activities of Daily Living↗
PubMed2004

Applying public health strategies to primary immunodeficiency diseases: a potential approach to genetic disorders.

Primary immunodeficiency (PI) diseases are a group of primarily single-gene disorders of the immune system. Approximately 100 separate PI diseases have been described, but <20 probably account for >90% of cases. Although diverse, PI diseases share the common feature of susceptibility to infection and result in substantial morbidity and shortened life spans. Most important, prompt diagnosis and treatment can now lead to life-saving treatment and result in marked improvements in the quality and length of life for persons with PI diseases. In November 2001, a workshop was convened by CDC in Atlanta, Georgia, to discuss ways to improve health outcomes among persons with PI disease. A multidisciplinary panel of persons knowledgeable in PI diseases and public health met to identify and discuss public health strategies that can be applied to PI diseases and possibly for other genetic disorders. A systematic assessment based on the established public health framework was applied to the growing group of PI diseases, whose diverse genetic mutations span multiple components of the immune system but all lead to increased incidence and severity of infections. During the meeting, specialists in clinical immunology, public health, genetics, pediatrics, health communication, and ethics from state and federal agencies, academic centers, professional organizations, and advocacy foundations discussed the four components of the public health framework as they relate to PI diseases. These four components include 1) public health assessment (application of traditional public health methods to assess the occurrence and impact of PI diseases on communities); 2) population-based interventions (development, implementation, and evaluation of screening tests administered to newborns and clinical algorithms for early recognition of symptomatic persons to facilitate the earliest possible diagnosis and treatment for PI diseases); 3) evaluation of screening and diagnostic tools (to ensure their quality and appropriateness for identification of patients with PI diseases); and 4) communication (communication with and information dissemination to health-care providers and the public to facilitate prompt and appropriate diagnosis and intervention). The working group's deliberations focused on challenges and opportunities, priority research questions, and recommendations for future action for these four components. These recommendations, developed by workshop participants, will be useful to medical and public health professionals who are evaluating methods to increase recognition of PI diseases and other genetic disorders.

Adolescent↗
PubMed1988

The idea of ageing: an historical and psychological analysis.

The idea of ageing can be traced back to the earliest written records. Prescientific beliefs were governed by animistic forms of thought leading to attempts to control ageing, disease and death through magic and supernatural agencies. The idea of ageing was gradually elaborated in Greek and Roman medicine and incorporated into religious beliefs and social practices. Ideas from the classical period were revived during the Renaissance, but modern scientific approaches to ageing did not emerge clearly until the 17th century, with systematic medical and statistical inquiries into the causes of death, and later, in the 19th and 20th centuries, into the biological mechanisms of ageing. The idea of an 'elixir of life' has been all but totally abandoned, although increases in the average length of life are expected to continue for some time. Refinements in the idea take account of the social and behavioural aspects of ageing.

Aged↗
PubMed2000

Correlated response in reproductive and life history traits to selection on testis length in Drosophila hydei.

Flies in the genus Drosophila have undergone striking evolutionary divergence in the size and number of sperm produced. Based on comparative studies of sperm length, testis length, and other reproductive and life history traits, including body size, age at first reproduction, and the number of sperm produced, macroevolutionary trade-offs resulting from the need to produce high-investment testes have been postulated. To understand better the microevolutionary processes underlying these interspecific patterns, we imposed replicated bidirectional selection for testis length for 11-12 generations on D. hydei, a species with 23.5 mm-long sperm and 30 mm-long testes. Testis length exhibited realized heritabilities ranging from 0.45 to 0.72. Following selection, traits were assayed for correlated responses. Thorax length, testis mass, sperm length, egg-to-adult development time, and posteclosion maturation time showed consistent positive correlated responses. Numbers of sperm produced and transferred to females, male longevity, female egg productivity, and seminal receptacle length did not show consistent correlated responses to selection on testis length. The pattern of correlated responses to testis length reveal the potential for the evolution of reproductive strategies to alter important life history attributes.

Animals↗
PubMed1987

Bone mineralization and growth in term infants fed soy-based or cow milk-based formula.

The purpose of this study was to evaluate the adequacy of a soy protein-based formula versus a cow milk protein-based formula for body growth and skeletal mineralization in the first year of life. Thirty-six healthy, term, appropriate for gestational age infants were assigned randomly and prospectively to one of two feeding groups and observed longitudinally over the first year of life. Group 1 infants (n = 18) were fed soy protein isolate-based formula (Isomil with Iron); group 2 infants (n = 17) were fed a cow milk protein-based formula (Similac with Iron). All infants were given the formula within the first 24 hours of life, and were fed the study formula through the first year of life. Weight, length, and head circumference were recorded; bone mineral content (BMC) and bone width (BW) were measured at one-third distal length (midshaft) of the left radius and ulna during the first 18 days of life, and again at 6 weeks, and 3, 6, 9, and 12 months postnatally. Baby food was provided to all infants, and except for type of formula, food intake was similar for all infants. Weight, length, and head circumference were normal in all infants and not different between groups. BMC and BMC/BW were similar for both groups at entry into the study. Group 1 infants had significantly lower BMC and BMC/BW at 3, 6, 9, and 12 months of age (P less than 0.05 to P less than 0.0001) compared with group 2 infants, but their values were similar to those in previously studied infants receiving human milk with vitamin D supplementation. The long-term implication of differences in bone mineralization in early infancy for long-term skeletal mineralization remains to be determined.

Animals↗