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PubMedDate not supplied

Projections of future numbers of dementia cases in Australia with and without prevention.

OBJECTIVE: To produce projections of the number of dementia cases in Australia from 2000 to 2050. These projections examine the effects of an ageing population on number of dementia cases and also the potential impact of preventive strategies that delay age of dementia onset. METHOD: Data from several meta-analyses of dementia prevalence and incidence were combined with age-specific population projections to arrive at estimates of future numbers of cases. A statistical model of dementia incidence was developed and used to estimate the effects of delaying onset by up to 5 years. RESULTS: Without prevention, prevalence of dementia is estimated to increase from 172 000 in 2000 to 588 000 in 2050. Over the same period, the incidence of dementia is estimated to increase from 43 000 to 143 000 new cases a year. Delaying onset by 5 years would decrease prevalence in 2050 by 44%. Even a 6-month delay would reduce prevalence by 6%. CONCLUSIONS: Ageing of the population will lead to a rapid increase in number of dementia cases and an increasing burden for the working-age population. However, even modest prevention efforts could lessen the impact.

Age Factors↗
PubMed1985

[Tempo and parity structure of Japanese fertility].

The present study is part of a larger project on the formal demographic analysis of Japanese fertility. It deals with the most elusive aspect of fertility, that is the tempo of fertility. The temporal aspect of fertility, particularly in terms of cohort fertility framework with speical reference to parity of women, has been emphasized by Whelpton and Ryder, but in the Japanese demography there have scarcely been studies of this aspect, probably due to lack of interest. In very recent years, however, interest has grown, reflecting the need for more accurate fertility projections in the future in connection with population projections. The present study is an application of life table techniques to explore the temporal aspect of fertility in Japan. 2 methods have been used. One is the age-marriage-parity specific net reproduction rate tables, which were first constructed by the senior author of this paper. The other is by Professor Chin Long Chiang at the University of California, Berkely. In the application of the former type, net reproduction rate tables were constructed for 3 dates -- 1970-71, 1975-76, and 1980-81. Through this method, it was demonstrated that recent fertility for the period 1980-81 was reduced, partly because of the decline in fertility in live-birth order of 1 and 2 among the relatively young ages up to 25 years old. On the other hand, for the ages up to 30 years old, some catching-up mechanisms took place. The 2nd method is by Chiang's new approach to the fertility table. According to his method, which was included in his new book entitled Life Tables and Its Applications, parity-oriented fertility tables have been constructed for the Japanese females for every year from 1971 through 1983, both inclusive. In these cases, denominator is for year z while numerator is concerned with yea z + 1. This method is particularly interesting since it can calculate waiting time for childbearing until the completion of family formation. Some of the findings indicated: 1) recent increases in both parity progession ratio and parity-specific fertility rate in low parity augur a future increase in fertility in the period measure in the near future; and 2) a shortening of the waiting time until the completion of family formation around 1981 and then the recovery of its lengthening in the years 1982 and 1983 suggest a recent trend of lengthening actual reproductive period which definitely contributes to an increase in fertility.

Asia↗
PubMed1994

Selection response for growth in a Spanish Merino flock.

Weight and growth data on 5,136 lambs, from 104 sires and 1,552 dams were collected during 5 yr (13 lambing seasons) of selection for high weaning weight in a single flock under range conditions. Ewes were culled based on fertility and replaced by ewe lambs selected for high weaning weight. Heritabilities of birth weight, weaning weight (30 d), preweaning daily gain, postweaning daily gain, and weight at 90 d, respectively, were .13, .09, .03, .15, and .11. Genetic correlations were generally high. Genetic and phenotypic improvements of weaning weight were 22 +/- 3.0 and 198 +/- 11.3 g per lambing season, respectively, with three lambing seasons per year. At the end of the experiment, phenotypic mean weaning weight was 2.4 kg higher than the initial values. Estimated and theoretical responses were similar in the sire population. At the 13th lambing season, average breeding value of 30-d weight of the ram population was 600 g higher than the mean initial breeding value in the base population. Projected average breeding value of the lamb population under random mating at the 23rd lambing season was equal to 404 g.

Animals↗
PubMed2002

[Mortality trends in cancer attributable to tobacco in Mexico].

OBJECTIVE: To describe the mortality trends of cancer attributable to tobacco smoking, particularly lung cancer, for the 1980-1997 period in Mexico. MATERIAL AND METHODS: Mortality trends were analyzed for each type of cancer associated to tobacco smoking, according to the International Classification of Diseases (ICD). Crude and adjusted mortality rates were estimated for the period between 1980 and 1997, by age, gender, basic death cause, and year of death. The gender ratio and the relative proportion were estimated for cases in the 35-64 age group and for the entire study population. Age population projections by Consejo Nacional de Poblacion (National Population Council), were used as denominators (1970-2010). RESULTS: The gender ratio for mortality rates for lung, esophageal, oral cavity and pharyngeal cancer was 2.10:1.00 (male:female). The gender ratio for laryngeal cancer was striking: 4.21:1.00, probably due to the higher prevalence of male tobacco smokers. The estimated relative proportion, using the total mortality due to malignant cancers between 1980-1997, was 12.31% for lung cancer, 1.71% for larynx cancer, 1.55% for esophageal cancer, and 1.49% for oral cavity/pharyngeal cancer. Previous tobacco smoking was correlated with the mortality rate trends for lung cancer (beta: 0.910, IC 95%: 1.097-1.797, R2 0.827). For the poorest social groups by federal entity, the correlation was inverted (beta: -0.510, IC 95% -0.170, -0.039, R2: 0.260). CONCLUSIONS: In Mexico, increased tobacco smoking, improved cancer diagnosis, and the demographic transition, are probably the main factors determining cancer mortality rates. However, other lifestyle associated variables, such as urbanization, physical activity, carotenoid intake, and other dietary and toxic substances like alcohol, may also influence the morbidity and mortality rates. Although tobacco-related cancer is a fast-growing public health problem having a poor prognosis, tobacco smoking, the main risk factor, could be eliminated by health education and promotion, together with publicity regulation and healthy taxation policies.

Adult↗
PubMed1991

Forecasting state and local population growth with limited data: the use of employment-migration relationships and trends in vital rates.

In this study, the rate of growth of state and local populations in the United States is related to the growth rate of national employment, and to demographic and economic features of the regions concerned, in order to make more realistic long-term population projections. Both natural increase and migration are taken into account in the model developed. "The model is estimated for two regions, the El Paso, TX, standard metropolitan statistical area (SMSA) and the State of New Mexico. Several statistical problems arise because of the limited number of available time-series observations. Fully dynamic historical simulations track the population quite closely, in one case never differing from the actual value by more than 1.17% and in the other never differing by more than 1.36%."

Americas↗
PubMed1991

Effects of fertility and international migration on changing age composition in Canada.

"This paper analyses the prospects for age distribution in Canada through 2036, based on today's age structure and expected trends in fertility and international migration. Simulating these two demographic components at extreme levels shows that tomorrow's aging is already built into the current age distribution, which is heavily marked by the post-war baby boom and the following persistent baby bust, and that neither fertility nor immigration can be seen as effective adjustment mechanisms for the changing age composition of Canada. Population projections using the component method are applied along with an age-specific growth-rate analysis."

Age Distribution↗
PubMed1993

The role of trans-Tasman migration in forecasting the New Zealand population.

"This article argues that, for the short to medium term, [New Zealand population] projections can be improved upon by adopting econometric methodologies which take explicitly into account the demographic-economic two-way interaction in certain components of international migration. Specifically, the article summarizes research on the causes and consequences of trans-Tasman migration, which is the dominant component of the volatility in New Zealand's net migration. It is shown how these findings can aid population forecasting."

Demography↗
PubMed1977

[The decline of fertility in Western Europe. II. Which fertility rate would be desirable in France? (author's transl)].

A way to try and assess the significance of such or such level in long term fertility is to work out population projections based on a variety of assumptions and to compare their different implications. The age pyramids of France until 2100 that derive from four contrasted evolutions of fertility are studied in the present article: completed fertility in birth cohorts ranging from 1.4 to 2.6 children per woman. While some demographic parameters are not much sensitive to the assumption made for the fertility level (e.g. percent of economically active people in total population), others are closely related to fertility (such as total number of inhabitants, percent of younger people or of older people in total population, annual rate of entry into economically active population). In France, where population density is much lower than in most neighbouring countries, a fertility level that would lay at -- or a little higher than -- replacement (i.e. 2.1 children per woman) can be considered as a desirable target.

Adolescent↗
PubMed2004

Population ageing in Lebanon: current status, future prospects and implications for policy.

During the past three decades, fast declines in fertility and mortality in Lebanon have created a compressed demographic transition, a growing trend towards survival into later life, and a larger proportion of elderly people in the population. Projections show that people aged 65 years and over are expected to constitute 10.2% of the population by 2025. Nevertheless, changes to the structure and composition of the population remain unmatched by any corresponding increase in support measures either through formal channels such as pension plans or through health or socioeconomic security measures such as the provision of subsidies for health care, home help or any form of nursing care. This means that an older person is forced to be dependent upon family support if it exists. We examine demographic trends of population ageing in Lebanon between 1970 and 1995 and provide projections until 2025. Variations in population ageing within the country are also considered. We also assess health care and social policy implications of demographic changes in the context of health and economic sector reforms initiated recently by the state, and explore their impact upon the expanding population of elderly people.

Adult↗
PubMed1992

[Youth in Africa: demographic and social implications].

"Using age-specific population projections for the period 1950-2025, the article examines the demographic and social implications of the importance of young age groups in Africa. School, employment and migration are of particular importance in the present context of political and economic crises affecting the continent." (SUMMARY IN ENG AND SPA)

Africa↗
PubMed1996

Transient retinal ganglion cells in the developing rat are characterized by specific morphological properties.

To determine whether dendritic development of mammalian retinal ganglion cells (RGCs) is affected by axonal target specificity, the morphology of three populations of maturing RGCs was examined. These included RGCs that exhibited either a transient, topographically incorrect, projection to the caudal superior colliculus (SC), or a transient projection to the caudal inferior colliculus (IC), in addition to a control group that exhibited a topographically correct projection to the caudal SC. Projection populations were identified by retrograde transport of rhodamine labeled latex microspheres injected into target nuclei. Labeled RGCs were then injected in vitro with Lucifer yellow to reveal the details of their dendritic morphology. Retinal ganglion cells making target errors, most of which ultimately die, were found to undergo a remarkable degree of morphological differentiation and could be categorized according to the adult type I, II, or III criteria. However, the relative proportions of these cell types were different among RGCs making transient connections versus those whose projections were preserved. Approximately half of the RGCs making topographically incorrect projections to the SC belonged to type III, in contrast to 6% that made a topographically correct projection. In addition, the population of cells sending axons to caudal IC did not include type III RGCs, but consisted of small type II neurons. The development of the basic dendritic form of each RGC type was only modestly influenced by its projection pattern; dendritic trees of cells making transient projections were essentially normal with only a slight, but statistically significant, reduction in dimensions. Moreover, dendritic remodeling was evident during maturation of neurons making either transient or normal projections. Together, these findings indicate that target specificity plays a relatively minor role on dendritic development of retinal ganglion cells.

Animals↗
PubMed1993

[National Household Forecasts 1993: households by size].

Population projections for household and family size and characteristics in the Netherlands are presented. "The household forecasts are based on a model in which mothers can be paired with their children.... The model is used for the birth generation of women 1930-1995.... According to the household forecasts the Netherlands had 6.2 million households in 1992. In 2010 [there] will be 1.1 million more.... The percentage of single households will rise from 30 to 36 while the percentage of two-person households will be stable at 31%. The percentage of households with three or more persons will decrease from 39 to 33." (SUMMARY IN ENG)

Developed Countries↗
PubMed2005

Prefrontal cortex in the rat: projections to subcortical autonomic, motor, and limbic centers.

This paper describes the quantitative areal and laminar distribution of identified neuron populations projecting from areas of prefrontal cortex (PFC) to subcortical autonomic, motor, and limbic sites in the rat. Injections of the retrograde pathway tracer wheat germ agglutinin conjugated with horseradish peroxidase (WGA-HRP) were made into dorsal/ventral striatum (DS/VS), basolateral amygdala (BLA), mediodorsal thalamus (MD), lateral hypothalamus (LH), mediolateral septum, dorsolateral periaqueductal gray, dorsal raphe, ventral tegmental area, parabrachial nucleus, nucleus tractus solitarius, rostral/caudal ventrolateral medulla, or thoracic spinal cord (SC). High-resolution flat-map density distributions of retrogradely labelled neurons indicated that specific PFC regions were differentially involved in the projections studied, with medial (m)PFC divided into dorsal and ventral sectors. The percentages that WGA-HRP retrogradely labelled neurons composed of the projection neurons in individual layers of infralimbic (IL; area 25) prelimbic (PL; area 32), and dorsal anterior cingulate (ACd; area 24b) cortices were calculated. Among layer 5 pyramidal cells, approximately 27.4% in IL/PL/ACd cortices projected to LH, 22.9% in IL/ventral PL to VS, 18.3% in ACd/dorsal PL to DS, and 8.1% in areas IL/PL to BLA; and 37% of layer 6 pyramidal cells in IL/PL/ACd projected to MD. Data for other projection pathways are given. Multiple dual retrograde fluorescent tracing studies indicated that moderate populations (<9%) of layer 5 mPFC neurons projected to LH/VS, LH/SC, or VS/BLA. The data provide new quantitative information concerning the density and distribution of neurons involved in identified projection pathways from defined areas of the rat PFC to specific subcortical targets involved in dynamic goal-directed behavior.

Animals↗
PubMed2006

Long-term care and dementia services: an impending crisis.

BACKGROUND AND OBJECTIVES: since the transfer of long-stay care to the independent sector, provision of places in care homes in the United Kingdom has varied in response to market trends, and has shown a consistent fall in the past 10 years. People with dementia constitute the largest diagnostic group affected by these changes, and are also likely to be the group that will determine future need. We therefore estimated the number and proportion of older residents in care homes who suffer from dementia relative to all those with dementia in the United Kingdom and projected future levels of demand on the basis of this data. DESIGN AND METHOD: the number of dementia cases in long-stay care was estimated from a random sample survey in south-east England and compared with data on age-specific prevalence. Projections of future demand were based on UK population projections for the next 40 years. MAIN RESULT: over half of all people with dementia in the United Kingdom are in care homes. The number of available long-stay places in care homes has fallen by one-sixth over the past decade. Projection of future demand suggests that well over double the present total places in care homes would be required by 2043 to maintain the present ratio of institutional to community services for dementia. CONCLUSION: this finding suggests an impending crisis of availability. A more realistic scenario calls for investment in affordable domiciliary care of good quality, but it will also depend on the acceptance of the fact that the main function of long-stay care for old people is now to provide for advanced cases of dementia, with consequent requirement for improvement in staff ratios and training.

Aged↗