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PubMed1976

Finding from Asia, Australia, Europe, and North Amercia on secular change in mean height of children, youths, and young adults.

Studies conducted during the past century in Australia, Canada, Japan, Norway and the United States indicate that the magnitude of secular increase in mean height rose with advancing age from childhood to mid-adolescence. Comparisons for a period approximating two-thirds of a century yield average increases in mean height of 12.2 cm for female youths age 12 years, and 12.5 cm for male youths age 14 years; for the same calendar span, the amount of secular increase in mean height declines from mid-adolescence to early adulthood. Comparisons of Belgian females, spanning a period approximating 130 years, yield increases in mean height of 18.1 cm at age 12 years, 11.9 cm at age 16 years, and 3.7 cm in early adulthood. For a period of 90 years, increases obtained on United States White males are 14.8 cm at age 14 years, 8.8 cm at age 17 years, and 5.3 cm in early adulthood. These and other displayed findings show clearly that the search for causes of secular change should take particular account of a phenomenon widespread among human populations, i.e., the phenomenon of childhood and early adolescent growth in body height proceeding at a faster pace in recent decades than about a century ago.

Adolescent↗

PubMed1983

Environment and secular changes in modern man.

The secular trend of human traits has so far been investigated mostly with respect to the morphological traits, mainly stature and body weight. However, some studies of changes in the physiological and psychomotor traits have also been published. The intergenerational changes concern changes in the development rate, magnitude of traits and sequence of symptoms of development. These changes are mainly due to changes in the environmental conditions, particularly of the living conditions. Another factor--though increasingly less expressed in present-day man--consists of genetic determination (especially survival). Migrations changing the gene frequency in populations represent the third factor. In the major part of economically developed countries interpopulational changes continue; in highly industrialized countries no further acceleration of sexual maturation takes place. Some studies from India and certain African countries point to a regression of physical development in children. Since stature and body weight are positive indices of health, they are important from the epidemiological standpoint and should be closely analyzed. This paper describes the findings obtained hitherto in studies performed in Poland or resulting from an analysis of materials from various countries.

Adolescent↗

PubMed2005

Obesity in 70-year-old Swedes: secular changes over 30 years.

OBJECTIVE: Secular increases in obesity have been widely reported in middle-aged adults, but less is known about such trends among the elderly. The primary purpose of this paper is to document the most recent wave of the obesity epidemic in population-based samples of 70-y-old men and women from Göteborg. Additionally, we will investigate the influences of physical activity, smoking and education on these secular trends. POPULATIONS AND METHODS: Five population-based samples of 3702 70-y-olds (1669 men and 2033 women) in Göteborg, Sweden, born between 1901 and 1930, were examined in the Gerontological and Geriatric Population Studies (H70) between 1971 and 2000. Cohort differences in anthropometric measures were the main outcomes studied. Physical activity, smoking habits and education were assessed by comparable methods in all cohorts. Subsamples of the women in the latest two cohorts (birth years 1922 and 1930) were also part of the Prospective Population Study of Women in Göteborg. In these women, it was possible to examine body mass index (BMI) and waist-to-hip circumference ratio (WHR) longitudinally since 1968. RESULTS AND CONCLUSIONS: Significant upward trends were found for height, weight, BMI, waist circumference (WC), WHR, prevalence of overweight (BMI> or =25 kg/m(2)) and obesity (BMI> or =30 kg/m(2)) across cohorts in both sexes. In 2000, 20% of the 70-y-old men born in 1930 were obese, and the largest increment (almost doubling) had occurred between the early 1980s and the early 1990s. In 70-y-old women the prevalence of obesity was 24% in 2000, a 50% increase compared to the cohort born 8 y earlier. BMI increased over time in all physical activity, smoking and education groups, with the exception of never-smoking men. Although 70-y-old women in 2000 were heavier than cohorts examined 8 y previously, data from the women studied longitudinally revealed that these differences were already present in earlier adulthood. In conclusion, the elderly population is very much part of the obesity epidemic, although secular trends in BMI were detected slightly earlier in men than in women. The health implications of these secular trends should be focused on in future gerontological research.

Aged↗

PubMed2002

Some aspects of secular changes in Hungary over the twentieth century.

Growth and maturation are considered the most reliable indicators of health status. Their progression rates in turn are strongly influenced by nutrition and socio-economic status, a well-documented relationship. The pattern of the so-called positive secular changes, i.e. the increase in size and earlier maturation, fits the populations' historical model of economic development very well. The historical, political and economic changes occurring in this century in Hungary have had a remarkably strong impact. Until World War I Hungary was an agrarian part of the Austro-Hungarian monarchy, its ethnic composition was most variegated. Both World Wars caused fundamental changes, namely in respect of post-war Hungary they were associated with marked territorial losses and considerable population mobility. In interpreting the developmental differences in the data collected before and after these wars one should take account of the important facts that, in addition to the changes in socio-economic conditions, affected the gene pool of the populations in Hungary. Over the past 100 years profound changes have occurred in the mean body size, growth rate and timing of maturation of the country's population. This paper is a brief analytic summary of the tendencies observed in adult stature, maturation and some socio-economic conditions. It also compares the cohorts of sub-populations as reflected by the reviewed reports. In summarizing the change in adult stature estimated by the data on recruits, soldiers and students of higher education, it could be stated that adult mean stature had become markedly taller in Hungary since the end of the fifties. However, any estimation of the absolute increment and the exact rate is severely biased by the variable character of the samples' representativeness. Similar problems arose in dealing with sexual maturation, because the retrospective and status-quo methods of assessment were found incomparable. Nevertheless, menarche was observed to have shifted to an appreciably younger age lately, a trend that by the end of the 20th century seemed to have reached a more or less stable level.

Anthropology, Physical↗

PubMedDate not supplied

Age at menarche in Flemish girls: current status and secular change in the 20th century.

The age at menarche in a national sample of 4894 Flemish schoolgirls was surveyed in 1979-1980. The probit estimate of the mean age at menarche was 13.20 +/- 0.02 years (SD = 1.25 years). This estimate falls well within the range of reported ages at menarche for girls in northwestern Europe, but is slightly later than those for French-speaking girls in Belgium and in France. Status quo secular data for the 20th century indicate a decline in estimated mean ages at menarche of Flemish girls from about 14.3 years before World War II to 13.6 and 13.2 years, respectively, among girls born just before and during the war. Subsequently, mean ages at menarche of Flemish girls are fairly stable between 13.0 and 13.2 years. These secular changes are of the same magnitude as those observed in other European countries.

Adolescent↗

PubMed1993

[Study on secular changes of cadmium concentration accumulated in main organs of Japanese].

With the development of the mining and manufacturing industries and the petrochemical industry, cadmium (Cd) has been used not only for metal products but also petroleum products. Recently, environmental pollution due to waste fluids and gases from factories using cadmium and also domestic waste materials has become a cause for concern. In this connection, studies on the accumulated levels of Cd in the human body, its age-distribution in the general population and its secular changes during the last decade would be useful for clarifying the degree of contamination in the human body and providing an index which could be used as a basis for preventive measures against environmental pollution. For this purpose, the levels of Cd accumulated in main organs of the human body were determined using forensic data 3 times at 5-year intervals starting in 1976. The age intervals starting in 1976. The age group having the highest Cd level was 50-59 years, old and the mean weights of Cd per wet weight of heart, liver and kidney were 0.421, 2,984 and 56.43 micrograms/g, respectively. Each of these organs in babies less than a year old exhibited lower Cd levels, but teenagers had levels close to those in adult. However, the level in each organ was lower in individuals over 60 years old. 4 distinct age-related increase in the level of Cd was found only in the kidney. The levels of accumulated Cd in the liver and kidney showed a rise during the last 10 years from 2.358 to 5.568 micrograms/g and from 43.95 to 73.47 micrograms/g, respectively, whereas the Cd level in the heart has remained about the same, i.e. from 0.207 to 0.181 micrograms/g.

Adolescent↗

PubMed1993

Studies on secular changes in the concentration of lead accumulated in organs and rib of Japanese.

As environmental pollution due to waste fluids and gases from factories using lead (Pb), as well as domestic waste materials, has become a matter for public concern, studies on the accumulated levels of Pb in man have become necessary for defining the degree of contamination in the ordinary population. For this purpose, Pb levels in tissues of 76 forensic cadavers were determined in order to investigate the age distribution of accumulated Pb, and 120 samples were used to clarify secular changes in Pb accumulation during the last decade in the general population. The age group showing the highest Pb level was 50-59 years, with mean Pb contents per unit wet weight of 0.262, 0.520, 0.427 and 4.479 micrograms/g for heart, liver, kidney and rib, respectively. Each of these organs in all age groups exhibited almost the same Pb levels, but babies less than one year old had levels close to those in adults. However, ribs in babies exhibited much lower Pb levels. The levels in each organ were lower in individuals over 60 years old. A distinct age-related increase in Pb levels was found only in ribs from age 0 year to 50-59 years. The Pb levels in the heart, liver, kidney and rib showed a decrease during the last 10 years from 0.188 +/- 0.073 to 0.006 +/- 0.003 micrograms/g, from 0.307 +/- 0.169 to 0.076 +/- 0.057 micrograms/g, from 0.287 +/- 0.145 to 0.021 +/- 0.011 micrograms/g and from 3.203 +/- 1.477 to 2.366 +/- 1.469 micrograms/g, respectively.

Adolescent↗

PubMedDate not supplied

Measuring the secular changes of the concentration of death causes.

In this paper, the authors introduce several kinds of measuring numbers for the analysis of changes in the causes of death. Under certain conditions, the so called diversity indices are good for this purpose. The authors discuss the results of their concrete studies on the basis of the patterns of tables of events made up according to age groups and types of indices. Comparing the-causes of death of the US for 1968 and 1975 death statistics, there is a tendency for secular increase in the latter. This can be observed in the majority of the important disease sections, thus it is of a divided character. The age group characteristics of the secular change in concentration can also be seen in the diagrams published. The described diagrams offer an opportunity for more detailed study of the changes in the causes of death from a human, biological point of view.

Age Factors↗

PubMed1982

Secular change in birthweight of Asian babies born in Birmingham.

We have studied changes in the birthweight of Asian babies born alive at this hospital between 1968 and 1978. In 1978 Pakistani babies were 139 g heavier but Indian babies only 25 g heavier than 10 years earlier. Contributing to these changes were significantly fewer short mothers and primiparae among Pakistanis, and non-significant increases in gestational age and intrauterine growth (that is, weight centile after allowing for gestational age, parity, and maternal height). Among Indians there were significant increases in maternal height and gestational age, but parity was reduced and intrauterine growth did not increase. In both groups there were fewer teenage mothers, but whereas among Pakinstanis birth intervals of less than one year were less common, there was no such reduction among Indian mothers. The secular change suggests that genetic factors are unlikely to be the major reason why Pakistani babies born in Birmingham are lighter than European babies, and that environmental factors play an important role. Efforts to increase birthweight need to consider both the mothers' physical environment during pregnancy and prepregnancy factors influencing growth in childhood, age at first pregnancy, and birth interval. The study shows a need to describe an 'Asian' population with details of their sub-ethnic structure. The sub-ethnic and secular differences further suggest that a single 'Asian' standard for birthweight and intrauterine growth may be inappropriate; the use of international reference data with which all infants may be compared is preferable.

Adolescent↗

PubMed1978

Secular change in sitting height and lower limb height of children, youths, and young adults of Afro-black, European, and Japanese ancestry.

During a large part of the last 100 years many human populations in Asia, Australia, Europe, and North America have increased in standing height. The amount of increase has risen with age from infancy to mid-adolescence, and diminished with age from mid-adolescence to early adulthood. In the present paper standing height is broken into two components and-for American black, American white, and Japanese groups-each component is found to (1) show substantial secular increase, and (2) yield a trend of quantitative difference similar to that of standing height. Average sitting height of Japanese males increased during the 33 years between 1937 and 1970 by 2.5 cm at age 8 years, 4.1 cm at age 14 years, and 2.9 cm at age 16 years; corresponding values for lower limb height were 3.7 cm, 5.3 cm, and 3.9 cm. During the 80 years following 1881, American white females ages 9 years and 13 years living in the Midwest increased in average sitting height by 4.6 cm and 5.4 cm, and in average lower limb height by 4.9 cm and 5.2 cm. For both dimensions of each racial group, secular change is greater at mid-adolescence than in early adulthood.

Adolescent↗

PubMed1993

[Secular changes of the mean birth weight in Japan during the past 20 years (single births, 1969-88)].

Using vital statistics (1981-1988) of the Japanese government, the mean birth weight (MBW) classified by sex was calculated from a birth weight distribution of the single births with 500g intervals for all Japan, prefectures and regions. These MBWs were linked with the MBW of 1969-1980 in our previous reports (Ref. 1) 2)). The MBWs of single births for twenty years (1969-1988) were investigated and it was pointed out that the MBWs classified by area (all Japan, prefectures and regions) were on the decrease recently and that the areal differences of the MBW were becoming large. For all Japan a secular change in the MBW was discussed for the term of a standard deviation, a skewness, a kurtosis, and relative frequencies of less than 2500g (weight class 1), those from 2500g to 3999g (weight class 2) and those of 4000g or more (weight class 3). These investigations revealed that birth weights of Japan have had a tendency to have a small standard deviation, a negative skewness, and a large kurtosis. Weight class 1 decreased until 1976 and increased after this year. Weight class 2 was on the increase up to 1988, and weight class 3 increased until 1973 and decreased afterward, as if it were accompanied by the MBW. For the purpose of confirming the contribution of each weight class to the annual change of the MBW, an analytical method for the weight frequency distribution was proposed as follows. Let M, M', pi and pi' represent the MBW of a given year (year A), the MBW of an another year (year B), the relative frequency of the i-th weight class in year A and that in year B, respectively. Suppose that M(i)'' represents the MBW when only the i-th weight class has pi as a relative frequency even in year B. Then, as the result of a fairly simple calculation, the difference between the MBW in year A and that in year B, M'-M, is obtained as follows; M'-M = sigma (1-pi') (M'-M(i)''). Therefore, the amount (1-pi') (M'-M(i)'') is able to be considered as a share of the i-th weight class in relation to the difference of M'-M. Accordingly, the share proportioned to the summation of the absolute amount [formula: see text] may represent the degree of the contribution of the i-th weight class to the difference, M'-M.(ABSTRACT TRUNCATED AT 400 WORDS)

Birth Weight↗

PubMed1990

Evidence for a secular change in obesity, height, and weight among Navajo Indian schoolchildren.

A survey measuring heights and weights of 1969 schoolchildren residing on the Navajo Indian Reservation was conducted in 1989. The findings were compared with National Center for Health Statistics (NCHS) reference data and with surveys of Navajo children from 1955, 1968, and 1981. Approximately twice as many children exceeded the 95th percentile of weight-for-age (11.2% of girls, 12.5% of boys) than would be expected for the NCHS reference population. The mean weight-for-height z scores exceeded those for the NCHS reference population for all ages in both sexes. Compared with data from 1955, mean heights increased 6.1% among boys and 4.4% among girls whereas mean weights increased 28.8% among boys and 18.7% among girls across all age groups. The data suggest that there has been a secular change in height, weight, and obesity in Navajo Indian children over the past 35 y.

Adolescent↗

PubMedDate not supplied

Secular changes in height and weight of Stockholm schoolchildren born in 1933, 1943, 1953 and 1963.

Secular growth changes of Stockholm schoolchildren born in 1933, 1943, 1953 and 1963 were studied through samples of about 2500 children in each year. Heights and weights at the ages 7, 10 and 13 years were obtained from school health records stored in the Stockholm city archives. The increase in height and weight at these ages was more marked between the children born in 1933 and 1943 than later, except for the girls aged 7, who had no increase in height. The increase in height between the later samples was at age 7 years practically none, at age 10 years about 1 cm/decade and at age 13 years 1-2 cm/decade. The body mass index (BMI) indicated a continuous trend towards a slimmer body build for Stockholm schoolchildren at the age of 7 years. At the ages of 10 and 13 years the BMI remained fairly stable for the cohorts born from 1943 to 1963.

Adolescent↗

PubMed2003

Secular changes in body height and weight in children and adolescents in Poznan, Poland, between 1880 and 2000.

AIM: A secular trend in body height and weight is well documented. The first observations concerning this phenomenon in Poland were made at the end of the 19th century. The aim of this study was to assess changes in body height and weight during the 20th century, with special emphasis on the last decade. METHODS: The results of body height and weight measurements obtained in eight subsequent surveys (1880-1886, 1922-1927, 1946-1950, 1960-1961, 1970-1971, 1980-1981, 1990-1991 and 1999-2000) were included in the analysis. Mean values were compared and differences between the surveys were analysed. RESULTS: In general, in the 20th century, children grew taller and heavier and reached final body height and weight more rapidly. The biggest differences in body height and weight in the 20th century, observed at growth spurt, were about 17 cm and 11 kg, respectively, for boys, and 13 cm and 13 kg for girls. The magnitude of secular changes in body height and weight in the 20th century was not stable. There were periods of increased and decreased intensity of acceleration of physical development (the 1950s and 1970s, and the 1960s and 1980s, respectively), as well as a period of deceleration (the 1940s). In the last decade, the tendency has been towards deceleration in most age groups studied. CONCLUSION: The acceleration of physical development in children in Poznan has now ceased.

Adolescent↗

PubMedDate not supplied

Secular changes in the growth of Toronto children during the last century.

A comparison of measurements of height is made from the late 19th century to early and mid-20th century in Toronto School children. Changes in total attained stature for age is compared for girls and boys to assess secular trends in height of urban children from Southern Ontario. The data clearly show a positive trend toward increased attained height for age from the earliest to most recent data. Comparison of the Toronto growth profiles to other published 18th and 19th century growth data demonstrates that the secular trend in the Canadian children is a reflection of the continued global trend towards increased height. The implications of this changing pattern over time are discussed in the context of changing urban health and nutrition in the greater Toronto area.

Adolescent↗

PubMed1982

Secular changes in age-specific cause of death in Sanday, Orkney Islands.

The purpose of this study is to describe secular trends in mortality for Sanday, Orkney Islands, Scotland between 1855 and 1974. Using information from death records, standardized crude mortality rates for each 10-year period were decomposed into 12 cause specific mortality rates. Differential contribution of each cause of death to the overall decrease in crude and age specific rates has been determined by comparing rates between periods of highest and lowest mortality. Although the decrease in rates was greater for females than for males, for both sexes, decreased mortality associated with respiratory diseases made the greatest contribution to the overall mortality decline. The decrease in death rates has its greatest effect during the reproductive period. Although results differ from those reported for England and Wales in the nineteenth century, they conform to estimates based on cross-national data from the mid-nineteenth century to the present.

Age Factors↗

PubMed1984

Secular change in growth of native children and adolescents at high altitude Huancayo, Peru (3,280 meters).

Stature and weight of native children, adolescents, and adults at Huancayo , Peru (3,280 meters), were measured in 1977, 1978, and 1982 and compared with mean statures and weights reported in previous studies. The data indicate that in Huancayo there has been a secular increment in child stature, sitting height, and weight from 1937 to 1978-1982. The observed changes in stature are related to a proportionally greater increment in leg length relative to trunk length. It is concluded that the observed secular increase in body size reflects changes in the standard of living and a greater influx of nonnative populations, which are usually characterized by greater stature than natives.

Adolescent↗

PubMed1983

International mortality trends and secular changes.

The decline in mortality from coronary heart disease (CHD) in several countries, notably the United States, in the 1970s has drawn attention to the need for monitoring secular trends in mortality and morbidity from this disease internationally and to discover the reasons for any upward or downward changes. Mortality trends for CHD in 27 countries are seen to vary widely, being very similar for men and women. It is, however, important to view CHD not in isolation but in terms of total mortality (TM) and other specific causes of death. For a more comprehensive picture, it is also necessary to go back two more decades into the 1950s, requiring the use of a broader diagnostic category "nonrheumatic and hypertensive heart disease" (HD). Using examples from selected countries, it is shown that CHD and HD run generally in parallel, that HD trends often though not always determine TM, and that cancer trends may or may not follow those for HD. Since preventive measures for CHD are likely to be beneficial for the prevention of other diseases as well, the concomitant study of trends for several chronic disorders ought to be rewarding.

Adult↗