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PubMed1998

Evaluation of the incidence and age distribution of bronchiectasis from the Finnish hospital discharge register.

The incidence and age distribution of bronchiectasis is at present poorly known. The aim here was to describe the use made of hospital services by bronchiectasis patients in Finland over ten years and to estimate the incidence of this disease. Data on hospital admissions for bronchiectasis were obtained from the register maintained by the National Research and Development Centre for Welfare and Health. Admissions and new cases during the period 1983-1992 were calculated by age and sex in relation to the total population. There were 5,710 admissions for bronchiectasis and 1,928 new cases. The occurrence of cases treated in hospital was 4.9 per million person-years at age 0-14 years, 103.8 at 65 years or over and 38.9 in the total population. The estimated incidence of bronchiectasis is low in Finland, especially in childhood, and efforts aimed at its treatment should now be directed specifically at the elderly population, which continues to exert considerable pressure on even a relatively well developed health service in this respect.

Adolescent↗
PubMed1993

Changes in age distribution of erythrocytes during pregnancy: a longitudinal study.

This prospective study was undertaken to evaluate age distribution of erythrocytes longitudinally throughout pregnancy. Serial estimates of density distribution of cells (DDC), reticulocyte count, red cell distribution width (RDW), and mean corpuscular volume (MCV) in a group of healthy pregnant women at 12, 16, 20, 24, 28, 32 and 36 weeks gestation and during the latent phase of labor (39.04 +/- 1.5 weeks). MCV increased constantly during pregnancy; however, the increase was not statistically significant. The mean reticulocyte percentage rose significantly at the 28th week, thereafter it remained at high levels until delivery. RDW increased significantly at the 20th week, remained at high levels until the 32nd week and thereafter declined towards the delivery. The cumulative DDC curve gradually shifted to the right during pregnancy, indicating a less dense cell population as the pregnancy progressed. In conclusion, a continuous alteration in age distribution of erythrocytes towards a younger cell population takes place from early pregnancy until the delivery of the fetus.

Adult↗
PubMed1990

Changing paternal age distribution and the human mutation rate in Europe.

All available evidence indicates that the human mutation rate increases with paternal age. In developed countries, a reduction in the proportion of older parents is a common feature of the marked changes in parental age distribution that occur as a result of family planning. We have related the current paternal age distribution in the European countries for which data is readily available, to a derived curve for paternal age-specific relative mutation rate. The results indicate that, to the extent that it is dependent on paternal age, the mutation rate has decreased considerably in developed countries during the past 50 years. The human mutation rate is a dynamic entity, continuously changing in response to social conditions.

Adult↗
PubMed2001

An operational research approach to estimating the age distribution of residence time in an HIV/AIDS core group.

An operational research approach is used to estimate the age distribution of residence time in an HIV/AIDS core group of gay men, employing only good public health data for administration, planning and decision-making. Any HIV/AIDS modelling involving a high-activity high-risk core group must allow for a restricted but variable residence time in the group. An earlier steady-state approximation by Bailey assumed an arrival process with negligible departures, followed by a departure process with negligible arrivals. That conjecture naturally overestimated the average residence time. An improved model, using age-dependent public health data on AIDS for some 4129 cases in gay men in San Francisco, has now been reanalysed to present the distribution of age at a fixed point of time close to the peak of the underlying HIV epidemic. It is important to note that these data, at any rate, have no appreciable age-dependence in the observed incubation periods. We have adopted the underlying infection dynamics of Jacquez et al. that recognizes an initial concentrated period of high infectivity in all HIV positives leading to a well-marked primary HIV epidemic. Maximum-likelihood estimation has been used to identify five major parameters with small standard errors. The residence model as a whole gives a good fit to the reanalysed data with chi(2)(4)=2.83.

Adolescent↗
PubMed2002

Markedly changed age distribution among patients hospitalized for acute myocardial infarction.

OBJECTIVE: To investigate trends in number of hospital admissions due to acute myocardial infarction (AMI) in different age groups during the last decade. DESIGN: Data on all AMI hospital admissions since 1991 were analysed by gender and by age applying 5-year age groups between ages 60 and 90, and < 60 and > or = 90 as separate groups. RESULTS: From 1991 to 2000 the number of hospital admissions for AMI was reduced by 18%. In men, AMI rates decreased in all age groups below 80 years and increased in older ages, while in women the corresponding breaking point between decreased and increased rates was 85 years. In the age group < 80 years, men and women included, the number of AMI admissions decreased by 29% (from 11,540 to 8233), while for those > or = 80 there was an increase of 25% (from 2917 to 3659). Over the decade the ratio of the numbers of AMIs in ages above and below 80 years increased from 0.25 to 0.44. CONCLUSION: Over the last decade a striking change in age distribution among AMI patients took place, with a marked decrease in age groups below 80 years, as opposed to an equally strong increase in the oldest age groups. The development with regard to trends for AMI morbidity in society has been more favourable than what appears from overall numbers of AMIs.

Acute Disease↗
PubMed2006

[Age distribution of transepithelial water loss in human nasal mucosa].

BACKGROUND: Dry nose is a common complaint in the elderly. Age distribution of transepithelial water loss of human nasal mucosa (TEWL) value was evaluated in this study. METHODS: Eighty-eight volunteers (50 men and 30 women) ranging from 10 to 75 years old were recruited for this study. Measurement of TEWL was performed on the inferior nasal turbinate. TEWL was measured with an evaporation meter applying Fick's law (Tewameter TM 300; Courage and Khazaka, Cologne, Germany). RESULTS: TEWL value tends to increase in order of age, indicating that the barrier function of epithelium may decline with age. CONCLUSION: The measurement of transepithelial water loss should be contributed to assess the efficiency of nasal mucosal barrier disorders in the elderly.

Adolescent↗
PubMed1993

Age distribution of histologic types of breast carcinoma.

The large number of cases in the Surveillance, Epidemiology and End Results (SEER) program of the US National Cancer Institute allowed a detailed analysis of the age distribution of the histologic types of invasive breast carcinoma. Between ages 50 and 85 years in females, the age-specific incidence rate shows little change for medullary, inflammatory and apocrine carcinomas; is about doubled for Paget's disease and for ductal, lobular, tubular and metaplastic carcinomas; and increases to 4 to 8 times the menopausal level for mucinous, papillary and signet-ring-cell carcinomas. The peri-menopausal break on the age-incidence curve is most marked for carcinomas of predominantly lobular origin and virtually absent for carcinomas of predominantly ductal origin. In males, the age distribution of papillary carcinoma is similar to that of all types combined, whereas that of mucinous carcinoma is skewed towards older ages, as in females.

Adult↗
PubMed2006

Age distributions, birth weights, nephrogenic rests, and heterogeneity in the pathogenesis of Wilms tumor.

BACKGROUND: The National Wilms Tumor Study (NWTS) constitutes a unique resource for study of clinical, pathologic, and epidemiologic features of Wilms tumor (WT). PROCEDURE: Data from NWTS-3,4,5 were compiled for 7,455 patients with tumors of favorable (FH) or anaplastic (AH) histology. The associations of birth weight (BW) and age-at-onset with gender, intralobar (ILNR), and perilobar (PLNR) nephrogenic rests, tumor focality, congenital malformation syndromes, and tumor histology were analyzed using descriptive statistics and linear regression. RESULTS: Mean BWs for male and female patients without PLNR were 3.52 and 3.36 kg, respectively, and for those with PLNR were 0.12 kg and 0.15 kg heavier. Mean age was 45 months for males with no rests whose tumors were unifocal and of triphasic favorable histology. ILNR or multifocality decreased the mean age by 18 and 10 months, respectively, whereas female gender, blastemal/FH or AH increased it by 3, 10, and 16 months. Over 90% of multifocal tumors occurred in the presence of demonstrated ILNR or PLNR or both. The apparent bimodality of the age distributions and later mean ages-at-onset for females with both unifocal and multifocal tumors were explained in part by the relative deficit in females of ILNR versus PLNR-associated tumors. CONCLUSIONS: These observations support the view that there are multiple pathways to Wilms tumorigenesis. They will facilitate selection of informative subgroups of patients for molecular analysis that may serve to identify the putative pathway for the majority of patients who cannot be classified provisionally on the basis of ILNR or PLNR.

Age Distribution↗
PubMed1991

The prevalence and age distribution of peripheral pulmonary hamartomas in adult males. An autopsy-based study.

This autopsy-based study defined the prevalence and age distribution of peripheral pulmonary hamartomas in 47,635 southern African miners examined between 1975 and 1988. The prevalence rate for white miners was 7.5/1,000 and for black miners 1.1/1,000. When directly standardised to the white men in the general population, the rates for white and black miners were 7.2 and 5.5/1,000, respectively. The prevalence of peripheral pulmonary hamartomas in both groups increased with age, from 0.8/1,000 in the third decade to 12.0/1,000 in the eighth decade. The study showed a much higher prevalence of peripheral pulmonary hamartomas for whites than previously reported. Furthermore, it documented the occurrence of these benign lung tumours in blacks, a fact that has previously been questioned. There appeared to be no significant difference in prevalence and age distribution between white and black miners, although the database for the black group was deficient for the later decades of life.

Adult↗
PubMed1999

Familial cancers in a nationwide family cancer database: age distribution and prevalence.

We calculated sex- and age-specific familial relative risks (FRRs) of cancer in offspring of cancer probands at 19 male and 20 female cancer sites, based on the nationwide Family Cancer Database from Sweden. The proportion of familial cancers among all cancers was also determined. The database contained 550,000 primary cancers. The familial risk at known sites: colon, breast, ovary, testis, skin (melanoma), nervous system, thyroid and other endocrine glands were confirmed. The FRR of thyroid cancer exceeded any other cancer and was over twice as high for male as for female offspring, and appeared to constitute an early- and late-onset component. Novel register-based findings were familial risks in cervical and uterine cancer, and in male offspring of male probands kidney and skin (mainly squamous cell) cancer. Familial risks were noted also for lung cancer, lymphoma and leukaemia but they may have largely environmental causes. The proportion of familial cancers depended on the site, ranging from 11% in prostate to 8.7% in female breast and to well below 1% at many sites.

Adult↗
PubMed1989

Effect of maternal age distribution and prenatal diagnosis on the population rates of Down syndrome--a comparative study of nineteen populations.

We analyzed published data from 1980-85 on maternal age specific rates of Down syndrome in nineteen malformation monitoring systems. In the comparisons, we used maternal age specific Down syndrome baseline rates collected in Sweden using multiple sources and from a period before intense prenatal diagnosis. We supposed that no real maternal age specific risk difference exists between different populations, and that ascertainment of cases is independent of maternal age. With these suppositions, most programs had an ascertainment level of 70-90%, and some had about the same but none had a higher ascertainment level than that in the Swedish baseline. Marked differences in maternal age distribution in the populations studied resulted in a 12.3% standard deviation of the average population Down syndrome rate. The highest theoretical rate (estimated from actual maternal age distribution and Swedish baselines) was found in Spain (20% above average), the lowest in Czechoslovakia (24% below average). The estimated average effect of prenatal diagnosis was a decrease of only 6%, but in Denmark it was 25% and in Sweden and France:Paris 13%.

Adult↗
PubMed1997

Epidemiological considerations of the age distribution of measles in India: a review.

This paper reviews the Indian data on age distribution of measles prior to large scale immunization. In metropolitan areas, the median age was about 24 months and virtually all the cases were recorded in children under 5, whereas median age in most of rural studies was < 4-< 5 years and all the persons were not affected until 10 years of age. The situation was in between in other areas. Since less than 10 per cent of the cases occurred before 9 months of age, this age is appropriate for routine measles immunization. The results also suggested the choice of age groups to be immunized during measles mass campaigns; the upper age may be 3 years in metropolitan city, 10 years in rural areas, and 5 years in the rest of the population.

Age Distribution↗
PubMed1996

The changing profile of homozygous beta-thalassemia: demography, ethnicity, and age distribution of current North American patients and changes in two decades.

BACKGROUND: The age of patients with homozygous beta-thalassemia is increasing because of better treatment and decreased births. A countering influence is immigration of ethnic groups with a high prevalence of thalassemia. METHODS: a questionnaire sent to 48 North American centers requested information about current patients with homozygous beta-thalassemia: age, clinical severity, and ethnicity. An 83% response was obtained. Twelve reference hospitals that participated in similar surveys in 1972 and 1984 were included. RESULTS: Five hundred eighteen patients with homozygous beta-thalassemia represent most North American patients. Four hundred forty-three (86%) of these had transfusion-dependent thalassemia major (TM); 75 (14%) had thalassemia intermedia (TI). Sixty-two percent were of Greek and Italian ancestry. There were approximately equal numbers of patients with TM in 5-year intervals between 0 and 25 years of age. Thereafter, the numbers of patients fell sharply. The mean age (+/- SD) of the patients with TM was 16.1 +/- 9.2 years. Striking differences were seen in Italian and Greek patients compared with those of other ancestries. Sixty-six percent of the 271 Italian and Greek patients with TM were older than 16 years of age, whereas 77% of the 172 patients of other ethnic groups with TM were younger than 15 years of age. The mean age of the 75 patients with TI was greater than that of the patients with TM. Seventy-three percent of African-American patients had TI, compared with 0% of Southeastern Asian patients. Comparisons of patients with TM from the 12 reference hospitals for two decades show increasing mean ages of TM patients (1973, 11.4 +/- 6.7 years; 1985, 14/2 +/- 7.3 years; and 1993, 16.1 +/- 9.2 years). CONCLUSIONS: There are probably only 750 to 1000 patients with homozygous beta-thalassemia in North America. Only about 15 to 20 new cases are diagnosed each year. The increasing mean age and age distribution indicate that modern therapies are effective, but immigration of non-Mediterranean ethnic groups with thalassemia has resulted in more, younger patients. TM is increasingly becoming a disease of young adults.

Adolescent↗
PubMed1992

[The relationship of clinical manifestations and age distribution in enterovirus infections--viral isolation and seroepidemiology in Aichi Prefecture].

We studied the epidemiology of enterovirus infection in Aichi Prefecture from 1985 to 1989. We examined the age distribution of aseptic meningitis patients (AM) and exanthematous disease patients (Ex) and a seroepidemiological study of echovirus type 7 (E7), E9, E18 and group A coxsackievirus type 9 (CA9), was performed. The results is as follows: 1) E7, E9, E18 and CA9 were isolated from AM and Ex but E6, E11 and group B Coxsackie viruses (CB) were isolated in fewer cases from Ex. 2) The AM was consistently increased from June to August. Whereas the Ex was seen in all seasons but a slight increase was noted between June to July, and enteroviruses (EV) isolation was increased in this season. 3) The AM occurred in 0 year olds and 4 year olds whereas the Ex was seen in 0 to 1 years. EV was mainly isolated from 0-1 year olds. 4) The relationship of clinical manifestations and age was very clear in E9 and E18, a higher proportion of children at 1 years or under were those of the Ex and most children of the latter part of 4 years were those of the AM. The Ex had the same results with E7 and CA9 but AM was increased in 0 years and 4 year olds. 5) We studied the age distributions of neutralizing antibodies against E7, E9, E18 and CA9. The positive rate of neutralizing antibody after prevalence rose between 2-5 years of age. There were few patients among the 2 to 3 year olds but the neutralizing antibody was raised in this age. I considered that reason the enteroviruses infected mainly the 2 to 6 year olds showing no clinical symptoms where as some of the 3 year olds had aseptic meningitis and some under 1 year had symptoms of exanthematous diseases.

Age Factors↗
PubMed2005

The macro determinants of health expenditure in the United States and Canada: assessing the impact of income, age distribution and time.

This paper examines the determinants of real per capita health expenditures in order to assess the impact of age distribution, income and time using American state-level data for the period 1980-1998 and Canadian province-level data for the period 1975-2000. Ageing population distributions and income explain a relatively small portion of health expenditures when the impact of time effects, which is a partial proxy for technological change, is controlled for. However, the impact of age is of more concern given that cost increases are concentrated in the last few years of life and there may be cohort effects as the "Baby-Boom" generation ages. There is an urgent need to better understand the exact mechanisms driving health expenditure increases given that time accounts for approximately two-thirds of health expenditure increases and that its effect is non-linear.

Age Distribution↗
PubMed1998

Pandemic versus epidemic influenza mortality: a pattern of changing age distribution.

Almost all deaths related to current influenza epidemics occur among the elderly. However, mortality was greatest among the young during the 1918-1919 pandemic. This study compared the age distribution of influenza-related deaths in the United States during this century's three influenza A pandemics with that of the following epidemics. Half of influenza-related deaths during the 1968-1969 influenza A (H3N2) pandemic and large proportions of influenza-related deaths during the 1957-1958 influenza A (H2N2) and the 1918-1919 influenza A (H1N1) pandemics occurred among persons <65 years old. However, this group accounted for decrementally smaller proportions of deaths during the first decade following each pandemic. A model suggested that this mortality pattern may be explained by selective acquisition of protection against fatal illness among younger persons. The large proportion of influenza-related deaths during each pandemic and the following decade among persons <65 years old should be considered in planning for pandemics.

Adolescent↗