Life span of Japanese male medical doctors.
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There have been few reports with regard to the life spans of medical doctors. The status of the medical doctors graduating from 1926 to 1974, alive or dead as of October 1996, was ascertained on the basis of the list of graduates from the School of Medicine, Hokkaido University. Excluding data on female doctors and those who died in battle during World War II, data on a total of 3,982 doctors were available for study. Their mortality as of October 1996 decreased in parallel with the graduation year. Their mean future life span at graduation was estimated to be about 52.88 years (95% CI, 52.45-53.31) through linear regression (r = 0.992). Their mean age at graduation was 25.17 years. This was not different from the future life expectancy at 25 years of age of the general population (52.35 years). The future life span of surgeons and gynecologists-obstetricians was shorter than that of the doctors of basic medical sciences and internal medicine. This difference might be accounted for by factors peculiar to each speciality (e.g., exposure to blood) or by the degree of stress from work. (+info)
United States life tables, 1997.
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The life tables in this report are current life tables for the United States based on age-specific death rates in 1997. Beginning with 1997 mortality data, complete U.S. life tables were constructed using a new methodology that replaces the abridged life table methodology used previously. The methodology is similar to that used in the decennial life tables. Also, life expectancy and other life table values are shown for ages 85 to 100 years for the first time as part of the annual U.S. life tables. Data used to prepare these life tables are 1997 final mortality statistics; July 1, 1997, population estimates; and data from the Medicare program. Presented are complete life tables by age, race, and sex. In 1997 the overall expectation of life at birth was 76.5 years, an increase of 0.4 years compared with life expectancy in 1996. Life expectancy increased from 1996 to 1997 for each of the four race-sex groups for which life expectancy is reported. Life expectancy increased for black males by 1.1 year (from 66.1 to 67.2), for black females by 0.5 year (from 74.2 to 74.7), for white males by 0.4 year (from 73.9 to 74.3), and for white females by 0.2 year (from 79.7 to 79.9). (+info)
Radiation risk and mammographic screening of women from 40 to 49 years of age: effect on breast cancer rates and years of life.
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The aim of this study was to evaluate the carcinogenic risks associated with radiation in mass mammographic screening. Assessment was in terms of breast cancer mortality and years of life for a hypothetical cohort of 100 000 women. Data were obtained on incidence, mortality and life expectancy for the female population of Stockholm. With a screening interval of 18 months at ages 40-49 years, a total absorbed dose to the breast of 13 mGy per invited woman; and an annual breast cancer reduction of 25% per year 7 years from screening start, the net number of years gained was at least 2800. However, using the highest absorbed dose reported in routine mammographic screening in Sweden (approximately 3 mGy per view), and the highest reported radiation risk in the literature, a programme entailing annual screening with 2 views would require at least a 20% annual reduction in breast cancer mortality to give a net benefit in both the number of years of life gained and number of breast cancer deaths avoided. This observation supports the conclusion that exposures with low absorbed dose are essential when performing mass screening with mammography among young women. (+info)
Response to methotrexate treatment is associated with reduced mortality in patients with severe rheumatoid arthritis.
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OBJECTIVE: This study investigated whether efficacious methotrexate (MTX) treatment has an impact on mortality of patients with severe rheumatoid arthritis (RA). METHODS: In this prospective, observational, one-center study, patients with severe RA refractory to other disease-modifying antirheumatic drugs started MTX treatment between 1980 and 1987. Patients were divided into 4 different groups according to their response to MTX treatment after 1 year (>50% improvement [n = 99], 20-50% improvement [n = 70], no improvement [n = 52], and discontinued treatment [n = 35]). After a followup of 7.5-15.3 years (mean 10 years), the numbers of deaths were assessed in the different groups. Standardized mortality ratios (SMR) were calculated by comparing the number of observed deaths in the study with the number of expected deaths in an age- and sex-matched sample of the general population. RESULTS: Two hundred seventy-one patients entered the study between 1980 and 1987. In 1995/1996, outcomes for 256 patients (94.5%) could be documented; 88 patients (34.4%) had died. In patients with >50% improvement after 1 year, the SMR was 1.47, while in patients with 20-50% improvement, the SMR was 1.85. In both groups combined, the SMR was 1.64 (95% confidence interval [95% CI] 1.11-2.17), compared with 4.11 (95% CI 2.56-5.66) in patients without improvement. Patients who had discontinued MTX treatment during the first year had an SMR of 5.56 (95% CI 3.29-7.83). CONCLUSION: Patients with severe RA who do not respond to MTX treatment have a poor prognosis, with >4-fold increased mortality compared with the general population, while RA patients who respond to MTX treatment have only a moderately increased mortality rate. (+info)
Trends in dementia-free life expectancy among elderly members of a large health maintenance organization.
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BACKGROUND: This study examined the secular trends of life expectancy without dementia among elderly American members of a health maintenance organization, and observed if an increased life expectancy is accompanied by an increase in the duration of life with dementia. METHODS: The data derived from two chronological 9-year prospective cohort studies of members of the Kaiser Permanente Medical Care Program of Northern California. The first and second cohorts included 2,702 and 2,926 people aged > or =65 years free from dementia at baseline. Life expectancy without dementia or dementia-free life expectancy (DemFLE) is defined as the average number of years a person is expected to live without dementia. Total life expectancy is equal to the sum of DemFLE and life expectancy with dementia. Estimations of DemFLE were based on mortality data and incidence of dementia, using double-decrement life tables. RESULTS: Between the first and second cohorts, all-cause mortality rates declined, while the incidence of dementia remained constant in both men and women. Among the males, total life expectancy increased at a higher rate than DemFLE. Consequently, the duration of life with dementia was extended in the second cohort. Conversely, among the females DemFLE increased at a higher rate than total life expectancy, thus the duration of life with dementia decreased in the second cohort. The median age of dementia onset was postponed by 2-3 years in the second cohort for females, and did not show any specific difference between the two cohorts in males. CONCLUSION: The trends of health expectancies suggest an extension of the duration of life with dementia for males and a compression of dementia for females. A decreased incidence of risk factors for dementia among females in the second cohort such as stroke may explain these trends. (+info)
Defining and measuring health inequality: an approach based on the distribution of health expectancy.
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This paper proposes an approach to conceptualizing and operationalizing the measurement of health inequality, defined as differences in health across individuals in the population. We propose that health is an intrinsic component of well-being and thus we should be concerned with inequality in health, whether or not it is correlated with inequality in other dimensions of well-being. In the measurement of health inequality, the complete range of fatal and non-fatal health outcomes should be incorporated. This notion is operationalized through the concept of healthy lifespan. Individual health expectancy is preferable, as a measurement, to individual healthy lifespan, since health expectancy excludes those differences in healthy lifespan that are simply due to chance. In other words, the quantity of interest for studying health inequality is the distribution of health expectancy across individuals in the population. The inequality of the distribution of health expectancy can be summarized by measures of individual/mean differences (differences between the individual and the mean of the population) or inter-individual differences. The exact form of the measure to summarize inequality depends on three normative choices. A firmer understanding of people's views on these normative choices will provide a basis for deliberating on a standard WHO measure of health inequality. (+info)
Reproductive longevity and increased life expectancy.
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BACKGROUND: Female life expectancy in developed countries has increased by 30 years in the twentieth century. AIM: To determine if there has been an increase in reproductive longevity. METHODS: We analysed age-specific fertility data from birth statistics for the USA, Canada, Japan, France, Sweden, the UK and Australia. RESULTS: Since 1940, birth rates for women aged 35 and over have declined. Among women aged 50 years and older, there has been no increase in births. Fertility rates in 1990 were 0.0 to 0.044 per 1000 women, with total numbers ranging from 0 to 60 births. CONCLUSION: The fertile years have not been prolonged in the cohort of women whose life expectancy has increased so dramatically this century. This suggests that reproductive senescence is tightly controlled and not extended by factors that enhance female longevity. Other physiological mechanisms may also be fixed within narrow age limits. (+info)
Group selections among laboratory populations of Tribolium.
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Selection at the population level or group selection is defined as genetic change that is brought about or maintained by the differential extinction and/or proliferation of populations. Group selection for both increased and decreased adult population size was carried out among laboratory populations of Tribolium castaneum at 37-day intervals. The effect of individual selection within populations on adult population size was evaluated in an additional control series of populations. The response in the group selection treatments occurred rapidly, within three or four generations, and was large in magnitude, at times differing from the controls by over 200%. This response to selection at the populational level occurred despite strong individual selection which caused a decline in the mean size of the control populations from over 200 adults to near 50 adults in nine 37-day intervals. "Assay" experiments indicated that selective changes in fecundity, developmental time, body weight, and cannibalism rates were responsible in part for the observed treatment differences in adult population size. These findings have implications in terms of speciation in organisms whose range is composed of many partially isolated local populations. (+info)