Social mobility of the father influences child growth: A three-generation study.

OBJECTIVES: The association between body height and social status is known. We were interested in the effect of intergeneration changes in social status on height. METHODS: Body height was measured in 2008 paternal grandfather-father-son and 1803 paternal grandfather-father-daughter triplets. The sample consisted of four child cohorts born in 1988, 1985, 1983, and 1980, and was measured annually from 6 to 11, 9 to 14, 11 to 16, and 14 to 18 years of age. Triplets were dichotomized according to grandfathers' occupation, into one "lower" and one "upper" grandparental class; and according to paternal education, into one "lower" and "upper" paternal class, resulting in four "family histories": two nonmobile (grandfathers and fathers stayed in the same social class), and two mobile histories (social class of fathers and grandfathers differed). RESULTS: "Upper" class fathers are taller than "lower" class fathers. This class effect on height persists into the third generation. Upward social mobility ("lower" class fathers receive secondary or university education) results in taller stature both in the fathers and in the children. The opposite applies for downward social mobility. "Upper" class fathers with only basic or vocational education lose the social advantage and remain shorter. So do their children. CONCLUSIONS: The class effect on height tends to persist into the next generation, but depends on education. Upward social mobility measured as a "better" education, results in taller stature, up to the third generation. The study highlights the importance of education as a major regulator of body height.

The effect of neighboring districts on body height of Polish conscripts.

ABSTRACT: The aim of the study was to investigate the correlation of heights of conscripts living in neighboring districts in Poland. The study used 10% of a nationally representative sample of 26,178 males 18.5-19.5 years old examined during the National survey of Polish conscripts conducted in 2001. The sample represented all regions and social strata of the country and included 354 different districts within 16 voivodships (provinces). Analyses were performed with the R statistical software. A small but significant correlation (0.24, p < 0.0001) was observed for height between 1st order neighboring districts. Correlations decreased with increased distances between neighboring districts, but remained significant for 7th node neighbors (0.18, p < 0.0001). Regarding voivodships (provinces), average height showed a geographical trend from the northwest (relatively tall) to the southeast (relatively short), and the correlation was stronger for first order neighboring provinces (0.796, p < 0.001). This study revealed clusters of tall people and short people, providing a support for hypothesis of the community effect in height. Small correlations between 1st order neighbors than in another country (Switzerland) may be associated with differences in geography, since in Poland there are no natural barriers (e.g., mountains) and road infrastructure is well-developed.

Self-reported versus measured body height and weight in Polish adult men: the risk of underestimating obesity rates.

BACKGROUND: In some epidemiological studies, self-reported height and weight are often used to save time and money. Self-reported height and weight are commonly used to assess the prevalence of obesity. The aim of this study was to assess the differences between self-reported and measured height and weight in adult men, and to determine how the accuracy of self-reported data depended on age and education. The prevalence of obesity was also calculated based both on self-reported and measured data. MATERIAL AND METHODS: Data were collected during two population studies carried out in Wroclaw in 2010. One study included 1,194 19-year-old males who reported for the health examination mandated by the National Conscription Board (younger group). The other group included 355 men between 35 and 80 years old who reported for a ten-year follow-up (older group). Data were analyzed separately for both age groups. RESULTS: Both younger and older subjects overestimated their height by 1.4 cm and 1.0 cm (1.4 cm, 95 % CI: 1.26, 1.51, and 1.0 cm, 95 % CI: 0.85, 1.26, respectively). On average, younger subjects overestimated their weight by 0.7 kilograms (95 % CI: 0.55, 0.92), whereas older subjects underestimated their weight by 0.9 kilograms (95 % CI: -1.15, -0.48). The lower the level of education, the more the subjects overestimated their height. CONCLUSIONS: Adult men systematically overestimate their height and underestimate their weight. The magnitude of the inaccuracy depends on level of education. When self-reported data are used, the prevalence of obesity is generally underestimated. Using self-reported data to calculate BMI can lead to a substantial underestimation of the proportion of underweight and obese individuals in a population. Finally, using self-reported values for height in studies on social inequality may lead to false conclusions.Background: In some epidemiological studies, self-reported height and weight are often used to save time and money. Self-reported height and weight are commonly used to assess the prevalence of obesity. The aim of this study was to assess the differences between self-reported and measured height and weight in adult men, and to determine how the accuracy of self-reported data depended on age and education. The prevalence of obesity was also calculated based both on self-reported and measured data. Material and methods: Data were collected during two population studies carried out in Wroclaw in 2010. One study included 1,194 19-year-old males who reported for the health examination mandated by the National Conscription Board (younger group). The other group included 355 men between 35 and 80 years old who reported for a ten-year follow-up (older group). Data were analyzed separately for both age groups. Results: Both younger and older subjects overestimated their height by 1.4 cm and 1.0 cm (1.4 cm, 95   %CI: 1.26, 1.51, and 1.0 cm, 95   %CI: 0.85, 1.26, respectively). On average, younger subjects overestimated their weight by 0.7 kilograms (95   %CI: 0.55, 0.92), whereas older subjects underestimated their weight by 0.9 kilograms (95   %CI: ­1.15, ­0.48). The lower the level of education, the more the subjects overestimated their height. Conclusions: Adult men systematically overestimate their height and underestimate their weight. The magnitude of the inaccuracy depends on level of education. When self-reported data are used, the prevalence of obesity is generally underestimated. Using self-reported data to calculate BMI can lead to a substantial underestimation of the proportion of underweight and obese individuals in a population. Finally, using self-reported values for height in studies on social inequality may lead to false conclusions.

Secular trends in body height and body mass in 19-year-old Polish men based on six national surveys from 1965 to 2010.

OBJECTIVES: The aim was to determine whether an intergenerational trend toward increased stature is slowing down, and whether body weight has recently increased among young men in Poland, as it has in Western European countries. METHODS: Data were taken from six national surveys of 19-year-old Polish male conscripts from cohorts 1965, 1976, 1986, 1995, 2001, and 2010. RESULTS: The mean stature of this population increased throughout the last 45 years from 170.5 cm in 1965 to 178.3 in 2010. However, the average gain in stature per decade declined from 2.4 cm in the period 1965 to 1976 to 0.8 cm per decade in 1995 to 2001, but increased to 1.0 cm in the last period. The average of body weight increased from 63.2 kg in 1965 to 73.1 in 2010 and body mass index (BMI) rose from 21.73 to 22.94 in the same period. The tempo of increase varied in different periods; between 1965 and 1986 an insignificant increase was observed (of circa 0.12); in 1986 to 1995 there was no increase, whereas the period of 2001 to 2010 witnessed a significant increase (of circa 0.76). CONCLUSIONS: The trend of body size and stature increase within the Polish population, although decelerating, remained positive and steady during the last 45 years. No significant impact of the past half-century's socioeconomic crises was observed in these measures of growth. We concluded that during the economic crises some effective mechanism protecting the living conditions of the children and youth were operating within the population.

Secular trends in BMI and the prevalence of obesity in young Polish males from 1965 to 2010.

BACKGROUND: Obesity is a serious public health problem, the prevalence of which is increasing dramatically all over the world. The aim of this study was to examine trends in body mass index (BMI) and the proportion of overweight and obese individuals among 19-year-old Polish males reporting for mandatory military fitness exams from 1965 to 2010. METHODS: Height, weight and BMI [weight (kg)/height (m(2))] in five 10% nationwide random samples of 19-year-old conscripts examined in 1965, 1986, 1995, 2001 and 2010 were analysed. RESULTS: From 1965 to 2010, mean BMI in 19-year-old Polish males increased from 21.7 to 22.9. The rate of change was not uniform, with a rapid increase in mean BMI from 1995 to 2010. Beginning in 1965, the proportion of men with a BMI over 25 has been steadily increasing from one decade to the next, and was four times higher in 2010 than it was in 1965. The rate of increase per decade was twice as high from 2001 to 2010 than it was from 1995 to 2001. In 2010, only 70.8% of young men were of ideal weight. CONCLUSION: Increase in obesity can be attributed to the social and economic changes brought about by the transformation of the country from a communist to a free-market economy in 1989. The challenges of the obesity epidemic for public health services and its impact on morbidity and life expectancy are also discussed.

Inter-generation social mobility modifies framingham risk score in Polish middle-aged men, but not in women.

In modern societies, there are regular social gradients in most health parameters, and also in the structure of morbidity and mortality. However, the significance of inter-generation social mobility for general health status still remains equivocal. This study was therefore performed in order to compare the effect of social mobility on coronary heart disease (CHD) risk between middle-aged Polish men and women. A total of 342 men and 458 women, aged 40 and 50 and inhabitants of Wroclaw, were examined. Risk of CHD was estimated using the Framingham Risk Score (FRS), calculated for each individual. Social mobility was defined as an inter-generation change in social status expressed as educational level between the examined individual and his/her father. Using two-variable regression models, it was demonstrated that FRS in men was determined by both their father's education level (beta=0.33, p<0.0001) and inter-generation change in educational status (beta=0.18, p=0.008). In contrast, FRS in women was related only to their father's education level (beta=0.35, p<0.0001), but not to inter-generation social mobility (beta=0.35, p=0.25). In particular, an incremental change in educational level among those men whose father had finished primary school at the very most or among those whose father had finished basic trade school was accompanied by a significant decrease in FRS (F=4.12, p=0.009 and F=3.25, p=0.04, respectively). It is concluded that inter-generation social mobility modifies CHD risk (as estimated using FRS) in middle-aged Polish men, but not in women. The precise mechanisms responsible for the observed sex difference in this phenomenon need to be established in further studies.

Biological condition of adult migrants and nonmigrants in Wroclaw, Poland.

Human migration and its economic, social, and demographic effects can lead to health consequences for individuals and populations. In the present study, we estimated differences in health status between migrant (those who had come to Wroclaw at the age of > or =16 years) and nonmigrant (those who had lived in Wroclaw since birth or had come with their parents) inhabitants of Wroclaw, Poland. Three hundred and sixty seven males and 496 females aged 40 and 50 underwent medical examination, and were asked to fill out a questionnaire comprising social, demographic, and life style information. Health status was assessed by blood pressure, heart rate, fasting lipid profile, glucose, height, and measures of fatness (BMI, WHR, sum of skinfolds). Comparisons were made based on Borkan's and Norris's profiles. Student's t-test showed significant differences in diastolic blood pressure, heart rate, total cholesterol, and glucose levels between two groups of males, in favor of migrants. Male migrants were also significantly taller than their peers born in Wroclaw. In females, migrants had significantly lower blood pressure and heart rate than nonmigrants. In interpreting the results two possible, not mutually exclusive, mechanisms are proposed: selective spatial mobility, and changes toward healthier life style as an adaptation to new urban environment.

Social inequality in premature mortality among Polish urban adults during economic transition.

Rates of premature mortality among adults are important measures of the economic and psychosocial well-being of human populations. In many countries, such rates are, as a rule, inversely related to the level of attained education. We examined changes in educational group-specific mortality rates among urban adults in Poland during the country's rapid transition in the 1990s from a socialist command economy to a free market system. Two census-based analyses of individual death records of urban dwellers aged 35-64 years were compared. We utilized all records of death, which occurred during the 2-year periods 1988-89 and 2001-02. Population denominators were taken from the censuses of 1988 and 2002. The age-specific mortality rates were used to evaluate absolute differences in mortality. To assess relative differences between educational levels, mortality rate ratios (MRRs) with 95% CI (confidence interval) were calculated using Poisson regression. A regular educational gradient in mortality persisted in each 10-year age group throughout the period covered by our data. Moreover, age-specific mortality rates declined steadily in all educational groups, and this decline was most marked in the two oldest age groups (45-54 and 55-64 years). The trend was accompanied by widening of educational differences in mortality as expressed by MRRs. Systemic political transformation in Poland has brought a mixture of beneficial and detrimental effects on the well-being of society. With regard to the changes in rates of premature mortality among adults, the benefits have prevailed, although individuals with the lowest educational level benefited less than those with the highest education.

The effects of fatness and fat distribution on respiratory functions.

BACKGROUND: Inverse relationships between respiratory function and indices of obesity and fat distribution have been reported, but it remains unclear which measure of obesity shows the strongest relationship with lung function. AIM: The study assessed the effect of fatness and fat distribution on respiratory function. SUBJECTS AND METHODS: A sample of 423 males and 509 females aged 40-50 years were examined in the Silesian Centre for Preventive Medicine, DOLMED, in Wroclaw in 1995. The strength of influence of height, body mass index (BMI), wait-to-hip ratio (WHR) and abdominal and subscapular skinfolds upon forced vital capacity (FVC) and forced expiratory volume in a 1-s expiration (FEV1) was assessed by multiple regression analysis. RESULTS: In males, FVC was strongly positively associated with height and BMI, but negatively associated with subscapular and abdominal skinfolds, WHR, and smoking. FEV1 showed a positive relationship with height, BMI and WHR. In females, both FVC and FEV1 showed significant positive associations with height, negative ones with subscapular skinfold, and no association with either WHR or abdominal skinfold. In males, respiratory function is affected to a similar extent by fat in the abdominal region and by fatness of the chest. In females, fatness of the thorax has the strongest relationship with respiratory function. CONCLUSION: Fatness tends to impair respiratory function in both sexes but these effects show a different pattern in males and females. In males, respiratory functions are significantly, and to a similar extant, affected by fatness in the abdominal region, both subcutaneous and visceral, and by fatness on the chest. In females, it is primarily subcutaneous fat on the upper thorax that affects respiratory functions, while visceral and subcutaneous abdominal fatness play little or no role.

Influence of height on attained level of education in males at 19 years of age.

In this study it is hypothesized that taller individuals are more likely to move up the scale of educational attainment compared with shorter individuals from the same social background. Three national cohorts of 19-year-old males were considered: 29,464 born in 1967 and surveyed in 1986, 31,062 born in 1976 and surveyed in 1995, and 30,851 born in 1982 and surveyed in 2001. Four social variables were used to describe the social background of each conscript in the three surveys: degree of urbanization, family size, and parental and maternal educational status. The educational status of each conscript was classified into two groups: (1) those who were secondary school students or graduates, or who had entered college, and (2) those who had completed their education at the primary school level or who had gone to a basic trade school. Multiple binomial logistic regressions were used to estimate the relative risk of achieving higher educational status by 19-year-old males relative to height and the four social factors. Consistently across the three cohorts the odd ratios (ORs) indicate that height exerts an independent and significant effect on the attained level of education at the age of 19 years in males (1986: OR=1.24, p<0.001; 1995: OR=1.24, p <0.001; 2001: OR=1.20, p<0.001). Two possible, not mutually exclusive, selective mechanisms are postulated and discussed: 'passive' and 'active' action.

The effect of the economic transition on the body mass index of conscripts in Poland.

The political and socio-economic transition initiated in Poland in the late 1980s is still continuing and has affected all social classes as well as all spheres of daily life of the people. The impact of this change on nutrition and health is examined here, by comparing the body mass index (BMI) of a 10% nationally representative sample of male conscripts aged 19 years (18.50-19.49), in 1986 (n = 26,396), 1995 (n = 22,612), and 2001 (n = 26,178). Mean BMI of young men did not change between 1986 and 1995, but then increased slightly from 22.0 to 22.3 between 1995 and 2001. There was also a significant and continuous increase in the variation of BMI in all social strata across the entire period 1986-2001. This effect is attributed to economic modernisation that has allowed increased diversity of life styles across occupational groups and between families. Sibship size was more important than socio-economic status in explaining variation in BMI after the political changes in 1990. The BMI-enhancing effect of small sibship size is attributed to nutritional intake, and to changes in food availability across the period under study.

Sex differences in the pattern of age-dependent increase in the BMI from 20-59 years.

This study tested the hypothesis of a linear increase of the BMI with age among adults. Materials comprised 32,762 occupationally active females and males 23-59 years age resident in Wroclaw, southwestern Poland. All subjects were medically examined in the course of health screening. The BMI increases linearly with age in women, but increases with age in men in two stages--a more intensive rise between 20-40 years and much slower increase between 40-60 years. This hypothesis was verified with a linear regression model in women but for men piecewise regression with a break at 40 years of age fits the age trends.

Are social-class differences in stature partly genetic? A hypothesis revisited.

Twenty-three different, socially homogenous groups of 19-year-old males were selected from a total sample of 57,000 Polish conscripts examined in 1986 and in 1995. Each group consisted of age-mates equated for six criteria of social background: 1) maternal and 2) paternal education, 3) maternal and 4) paternal occupational status, 5) number of children in the family, and 6) degree of urbanization of the subject's locality of residence. Within every one of the 23 groups, subjects who at the age of 19 years were secondary-school or college students, were taller than socially similar peers, who by that age had never moved beyond the level of basic vocational school. Thus, a significant association exists between an individual's potential for upward social mobility and tallness. Such associations must be taken into account when considering the origin and nature of the commonly observed taller stature of the upper over the lower social strata in present-day industrial societies. Am. J. Hum. Biol. 12:97-101, 2000. Copyright 2000 Wiley-Liss, Inc.

Variation in subcutaneous adipose tissue distribution associated with age, sex, and maturation.

Age-, sex-, and maturity-associated variation in subcutaneous adipose tissue (SAT) distribution is reviewed and then considered longitudinally in a sample of Polish youth. Current study of adipose tissue distribution places considerable emphasis on abdominal adiposity, specifically intra-abdominal or visceral adipose tissue (VAT). Most studies of children and adolescents do not include an abdominal skinfold, and when it is available, the skinfold is grouped with others as a sum of skinfolds. Correlations between abdominal VAT and SAT based on computerized tomography in non-obese children are moderate to high, and those between the suprailiac and abdominal skinfolds and abdominal VAT are moderately high. Changes in three individual skinfolds (triceps, subscapular, abdominal) and ratios of the skinfolds were considered by chronological age and relative to the timing of peak height velocity (PHV), and in children of contrasting maturity status in participants of the Wroclaw Growth Study, 193 boys and 197 girls, who were followed longitudinally from 8 to 18 years of age. Individual skinfolds behave differently during childhood and adolescence, and the changes are influenced by the timing of the adolescent growth spurt. Sex differences in estimated velocities are negligible up to about 2 years before PHV; then velocities tend to be higher in girls. The velocity of the triceps skinfold is negative in boys just before and after PHV; estimated velocities for the trunk skinfolds are positive through the growth spurt in both sexes, and are somewhat greater after PHV, especially in girls. The individuality of changes in individual skinfolds during the adolescent spurt contributes to changes in the relative distribution of SAT at this time. The timing of the adolescent growth spurt is an important factor influencing the distribution of SAT both in the total sample and in youth classified as early and late maturing. Am. J. Hum. Biol. 11:189-200, 1999. Copyright 1999 Wiley-Liss, Inc.

On the independence of adult stature from the timing of the adolescent growth spurt.

Longitudinal studies have shown repeatedly that little or no correlation exists between the timing of the pubertal spurt in stature and adult stature (AS). However, the possibility seems to have been overlooked that such near-zero correlations may, at least theoretically, be an artefact resulting from two opposite tendencies that cancel each other out: a hypothetical "biological" tendency for early maturers to end up as slightly shorter adults and a socially induced tendency, resulting from the existence of social gradients in growth, for accelerated maturation to be accompanied by taller A.S. Data of the Wroclaw Growth Study (355 fitted growth curves) were used to see whether making a sample socially more homogeneous produces any increase in the correlation between age at PHV and AS. No such effects were found. Thus the validity of the view is confirmed that genes controlling the timing of the spurt also affect the shape of the growth curve in such a way that the shorter time available for completion of growth in the early maturers is compensated for by a greater intensity of the spurt itself. © 1994 Wiley-Liss, Inc.

Monitoring the dynamics of social stratification: Statural variation among polish conscripts in 1976 and 1986.

The effects of three factors in the social environment on variation in stature were evaluated in two large samples of 19-year-old Polish conscripts, one examined in 1976 (birth cohort 1957) another in 1986 (birth cohort 1967). The factors were: A) population size of the locality of the conscript's habitation, B) occupational-educational status (OES) of the father, and C) size of the conscript's sibship. In each cohort, stature decreased monotonically with decreasing population size, decreasing paternal OES and increasing sibship size, each factor exerting a significant influence on stature even after the influences of the other two were partialled-out by analysis of variance (ANOVA) procedures. However, the order of the strenght of the influences has changed from B > C > A in 1976 to C > B = A in 1986. The most notable change was the decline in the importance of factor B. The condition of being a peasant's son depressed stature less in 1986 than in 1976, but the stature-depressing effect of the condition of being a rural dweller, as well as that of coming from a large family, has not diminished. Overall, secular gains in stature among groups lowest on the statural and social scale in 1976 have been more intense than among those highest on these scales, which resulted in an attenuation of some social contrasts in stature from 1976 to 1986. © 1992 Wiley-Liss, Inc.

Urbanization-dependent gradients in stature among polish conscripts in 1976 and 1986.

On the basis of two successive surveys of 19-year-old Polish conscripts, one in 1976 and another in 1986, secular trends in stature and the relationship between stature and population size of locality of habitation were examined. In spite of the serious economic crisis in the early 1980s and a rather abrupt cessation of the trend towards earlier menarche in Poland between 1977 and 1987, the trend towards taller stature continued unabated and was intense (2.0 cm in the general population). In 1976, stature decreased systematically with decreasing population size in the following order: (1) cities over 500,000, (2) cities between 100,000 and 500,000, (3) towns between 25,000 and 100,000, (4) towns below 25,000, and (5) villages. A similar gradient persisted in the 1986 survey. In 1986, about one-half of the total statural gradient was accounted for by the gap between rural conscripts and those next on the urbanization scale, i.e., conscripts from the smallest towns, and the magnitude of this gap was unaltered during the decade. However, the rural-large city gap has declined from 3.6 cm in 1976 to 2.8 cm in 1986. The relative shortness of rural conscripts and the tallness of their large-city age peers are consistent with the pattern of social variation in stature and maturation rate observed among Polish school children and with the country's postwar economic and social history.