Secular trend in height in Al Ain-United Arab Emirates

Correlation between cycles in human stature and those in economic variables is well established. A recent review of international trends in this area provided information from most parts of the world but none on Arabs in the Middle East or more specifically the gulf region.The United Arab Emirates experienced a transformation in economic and social life followed the discovery of oil in the late 1960s and the wealth that it generated. No data is available on human growth at this period of time because its population never had health services prior to the 1970s. A study on conventional cardiovascular risk factors in 2004-2005 included 817 randomly selected national adults (≥18 years) from both genders. The relationship between height and age in this study showed both men and women have increased in height with time demonstrating the secular change in height most likely a result of changing socioeconomic factors.     

Secular trend in body height and weight of Australian children and adolescents

Secular changes in growth and maturation have been well documented in various world populations, with secular increase especially noticeable in the developed countries. To assess the trend in both adult size and tempo of growth we compared the data on stature and body weight obtained in 1992-1993 from 1,804 Melbourne school students aged 5 to 17 with historical data collected from white Australians during the last 100 years. We illustrate the age-dependent trend in stature and body weight by means of regression surfaces. These were constructed by fitting local regression models to historical data and by simple plots showing the overall, and per decade, secular increase in both these measures at peripubertal and adult ages. Because of limited information on sample sizes and variability provided by the historical data, statistical comparisons have been performed only between the present 1992-1993 survey and two earlier independent surveys conducted in 1985 and 1970. The results have shown secular increase in adult stature over the last century, with the rate of increase varying between 0.4 and 2.1 cm/decade in males and 0.01 and 1.6 cm/decade in females. While secular increase in stature has significantly slowed down during the last two decades, the increase in body weight is still continuing at a high rate, and this increase is more pronounced in females. The period of strong secular increase, especially in the tempo of growth, coincided both with the shift toward earlier menarche and the improvement of socioeconomic conditions of the Australian population. The need for further studies to identify factors determining the continuing increase in body weight is emphasized, and caution in using the existing national growth standards for stature and weight is recommended.     

Secular changes in body formation of greek students

Anthropometric dimensions of 1520 students of Biology at University of Athens in Greece were analysed to determine secular changes of height and body proportions during a 20 year period. Since, 1970, means of standing height, subischial length, and cormic index have been increased, although the rate of increase from 1986 to 1990 has been rather slow. On the contrary the mean sitting height is stable, and cormic/ subischial index have been declined during the same period. There are no data for comparing this sample with the general population, but we suppose that these changes in the body formation is common as a result of the modern way of life.     

Population demography and social structure changes in Eulemur fulvus rufus from 1988 to 2003

Eulemur fulvus rufus has been described as having stable multi-male/multi-female groups, a male-biased sex ratio, and female philopatry. However, in a 16-year study of this subspecies we documented a great deal of demographic change as several groups permanently fissioned, some groups disappeared, and new groups formed. We split the dataset into two periods, 1988 to 1993 and 1994 to 2003, which coincided with the first disappearance of a study group (in August 1994) and the first permanent group fission (in December 1994). The average group size decreased by nearly half between the study periods (10.5-5.6), while the frequency of group membership changes increased (2.0-8.3 times/year), and the birth rate decreased (0.56-0.38). Females, as well as males, immigrated into study groups and transferred between groups, something that has been rarely seen in this subspecies. We also found a significant decline in the amount of fruit from the earliest part of the study to the latter part of the study. Study groups did not switch to other types of foods during periods of fruit shortage, but traveled outside of their home range areas more often over the study period. Finally, the density E. f. rufus decreased in the study area while the densities of their main food competitors, Varecia variegata and Eulemur rubriventer, increased. Although few primate populations are numerically stable over time, we suggest that female behavioral responses to decreases in fruit availability may have influenced some of the demographic changes we witnessed in this study.     

Secular changes of pelvis in Croatian perinatal women

The goal of the study was to examine secular changes of pelvic size in parturient women over the 25-year period from 1985 to 2009. Data were collected from randomly selected patients’ medical records of 2414 parturient women from four time periods (1985–1986, 1992–1994, 2000–2002, and 2007–2009). Three different pelvic measurements were collected: distantia spinarum, distantia cristarum, and distantia trochanterica. Regression analyses were conducted in order to test predictors of pelvic dimensions. The multivariate analysis of covariance (MANCOVA) was used to test changes in pelvic dimensions over time, with body mass index (BMI) as a covariate.     

Longitudinal study on growth in height in Polish boys and girls

Physical growth and development of children, determined by endogenous factors (genetic and paragenetic) is modified by numerous exogenic ones. This affects differentiation of ways of growth in individual children. In order to estimate the individual growth patterns and changes in growth rate as well as differences in growth of boys and girls, one must observe the process of growth of the same children and over a period of many years (longitudinal study). Such longitudinal study is the only way to provide information about the variability of growth and growth velocity at each age.     

Systemic changes in body structure of 17–18-year-old schoolboys

The purpose of this study was to assess the systemic structural changes in the body build of 17-18-year-old schoolboys in the final years of Tartu secondary schools within a height-weight classification dividing anthropometric variables into 5 SD-classes. Weight and height, 9 length, 8 breadth and 2 depth measurements, 16 circumferences and 12 skinfolds were measured. From these 5 length measurements and 53 indices were computed, which characterise the ratios of various parts of the body to body height, to upper and lower limbs' length and body composition. The subjects (n = 253) were divided into five standard deviation classes according to height and weight (Kaarma 1981, 1995). In the first three classes height and weight were proportional: (1) small height--small weight, (2) medium height--medium weight and (3) big height--big weight. In the fourth and the fifth class height and weight were non-proportional. In the fourth class weight was preponderant over height, and in the fifth class height was preponderant over weight. It was proved that a statistical difference exists between the opposite classes--the fourth and the fifth class. It was also revealed that the three proportional classes differ from each other significantly. Increase in body height and weight leads also to an increase in length, breadth and depth measurements, bone thicknesses, circumferences and skinfolds. Rohrer index, body mass index, total percentage of fat by Siri, absolute and relative mass of fat tissue increased from the small to the large class. The relationship of the length, width, and depth measurements, circumferences and bone thicknesses to height remains almost unchanged throughout the proportional classes. These investigations support the position that the whole body model may be reconstructed from body height and weight.     

Secular changes in craniofacial morphology of the Portuguese using geometric morphometrics

This study examines patterns of secular change in cranial morphology in the New Lisbon collection, a documented skeletal collection from Lisbon, Portugal with birth years from 1806 to 1954. This period represents a time when Lisbon was undergoing increased urbanization and population growth, as well as changes in mortality and fertility patterns. Previous studies from the U.S., Europe, and Japan have reported significant secular changes in cranial morphology over the past 200 years. In the current study, secular changes were analyzed using three-dimensional geometric morphometrics methods. The results from this study demonstrate a significant change in cranial morphology over the roughly 150-year period. Allometry was rejected as a causal factor of this change because there was no association found between temporal change and size. The pattern of temporal change is similar to that observed in other populations in the U.S., Europe, and Japan, including decreased facial breadth and a more inferiorly placed cranial base. This study, along with previous research, suggests a similar pattern of change occurs in genetically and geographically diverse populations experiencing modern environmental conditions. We argue that because the secular changes are focused in the cranial base, a region of the skull that experiences a relatively early growth curve, changes related to declines in childhood morbidity and mortality are likely important factors related to the observed changes.     

Secular changes are different in distinct subgroups of the growing population

The change of living conditions in East Germany after the German reunification in 1990 led to intensive secular changes in growth and development. Anthropometric data of height, weight, BMI and thickness of the subcutaneous fat layer are compared from two cross-sectional samples of German children and adolescents aged 6 to 18 years. The first sample was measured around 1989 and the second 10 years later around 1999. Both samples contain children and adolescents from the urban as well as from the rural population. The secular changes reported here are based on the comparison of medians of height, weight, BMI and subcutaneous fat layer thickness calculated for yearly age categories. Subsequently, medians of the 10% border categories are compared. These border categories contain the 10% smallest, lightest, slimmest or leanest subjects and the 10% tallest, heaviest, most corpulent or most obese subjects respectively of a yearly age category. The young generation shifted between 1989 and 1999 to a taller stature in the small as well as in the tall category. The secular pattern of measurements, which mark corpulence, is sex-specific and differs from that of length measurements. In general the light or lean subjects changed only little, however, there are clear age- and sex-specific changes in the upper border categories. Weight and BMI increased markedly in the upper border categories in young preadolescent children, but did not change much in adolescent boys of these category aged 15 and 16 and decreased in adolescent girls. Also the subcutaneous fat layer increased in the upper border category in preadolescent children, but decreased in adolescent boys and girls.     

Secular changes in growth and obesity in perinatal population

The survey was conducted during the last 25 years and included 2414 healthy women who delivered in "Sestre milosrdnice" University Hospital Center in Zagreb, Croatia and their newborns. The aim was to establish the secular trend of some anthropological factors through two generations. Anthropological features such as pre-pregnancy weight, body mass index before pregnancy, height, age, place of residence, educational level, parity and the newborn weight were registered. The study was randomized. The mothers from the city of Zagreb and the surrounding villages, rural areas are examined. The women age was different and also different levels of education and socioeconomic status. The study included women who had not given birth yet, who had delivered once, twice, and three or more times. Maternal height in 25 years increased by 3.1cm. and increases with education. The pre-pregnancy weight increased 2.8 kg and increases with age, parity and rural life. The body mass index (BMI) which the women had before pregnancy was calculated, and according to its value the participants were divided in three groups: with normal weight, overweight and fat. Among the studied periods BMI does not differ significantly, but does differ significantly with respect to the ordinal number of births, parity, age and living environment. Higher BMI was associated with deliveries to heavier children.     

Secular changes in height, body weight, body mass index and pubertal development in male children and adolescents in Krakow, Poland

This study examined the secular changes in height, body weight, body mass index and pubertal development in male children and adolescents in Krakow (Poland) over the past 80 years, with an emphasis on the last decade (2000-2010). The survey of the population of Krakow is a continuation of observations conducted in that area for many years. The analysis aims to determine whether in the last decade Krakow still witnessed the secular trend, and what form the trend took. The body height and weight, and body mass index (BMI), of 1862 boys aged 3.5-18.5 years were analysed, against the background of a survey series from the years 1938 (N = 1801), 1971 (N = 2045), 1983 (N = 3124) and 2000 (N = 2328). The mean body height, in almost all age categories, was greater than in the past; however the final height over the last decade remained the same. The mean values of body weight and BMI increased, especially in the last decade. Also, an acceleration of puberty in boys was observed. The last 10 years saw an over 3-month decrease in the age of initial appearance of pubic hair in boys. In conclusion, the last decade saw cessation of the growing taller trend: maximum body height stabilized at approximately 179 cm, but weight and BMI increased. Also, a distinct acceleration of puberty was noticed. Lack of height increase, at the same time as weight gain and puberty acceleration, indicate a progressing developmental disharmony.     

Secular trends of sizes at birth in Japanese healthy infants born between 1962 and 1988

Body sizes at birth are important clinical indicators widely used for evaluation of prenatal growth. Japan had significant socioeconomic improvement around the 1960s, and these environmental changes may influence physiologically prenatal growth. Furthermore, in Japan, measurements of size at birth for birth certificates are weight and height. Thus, we can refer to annual data on weight and height, but not on head and chest circumference at birth. In this study we measured the weight, height, and head and chest circumference at birth among 6,563 Japanese singleton healthy infants, annually in 1962 and 1988, and examined secular trends of these anthropometric measurements. The boys consistently exceeded the girls in all four variables. Birth weight and height increased significantly from the 1960s to '70s, but did not differ between the '70s and '80s in both boys and girls. Secular trends of head and chest circumference were different from them. In both boys and girls, head and chest circumference increased significantly from the '60s to the '70s, but decreased significantly from the '70s to the '80s. No difference of head circumference during the '60s and '80s was found, but the difference of chest circumference was found. Size at birth was likely to increase from the '60s to '70s in Japan. These findings suggest that the environmental changes such as socioeconomic improvements influence the prenatal growth.