Rain,temperature, and child–adolescent height among Native Amazonians in Bolivia

Background: Global climate change and recent studies on early-life origins of well-being suggest that climate events early in life might affect health later in life.

Aim: The study tested hypotheses about the association between the level and variability of rain and temperature early in life on the height of children and adolescents in a foraging–farming society of native Amazonians in Bolivia (Tsimane').

Subject and methods: Measurements were taken for 525 children aged 2–12 and 218 adolescents aged 13–23 in 13 villages in 2005. Log of standing height was regressed on mean annual level and mean intra-annual monthly coefficient of variation (CV) of rain and mean annual level of temperature during gestation, birth year, and ages 2–4. Controls include age, quinquennium and season of birth, parent's attributes, and dummy variables for surveyors and villages.

Results: Climate variables were only related with the height of boys age 2–12. The level and CV of rain during birth year and the CV of rain and level of temperature during ages 2–4 were associated with taller stature. There were no secular changes in temperature (1973–2005) or rain (1943–2005).

Conclusion: The height of young females and males is well protected from climate events, but protection works less well for boys ages 2–12.     

Rural–urban variations in age at menarche,adult height,leg-length and abdominal adiposity in black South African women in transitioning South Africa

Background: The pre-pubertal socioeconomic environment may be an important determinant of age at menarche, adult height, body proportions and adiposity: traits closely linked to adolescent and adult health.

Aims: This study explored differences in age at menarche, adult height, relative leg-length and waist circumference between rural and urban black South African young adult women, who are at different stages of the nutrition and epidemiologic transitions.

Subjects and methods: We compared 18–23 year-old black South African women, 482 urban-dwelling from Soweto and 509 from the rural Mpumalanga province. Age at menarche, obstetric history and household socio-demographic and economic information were recorded using interview-administered questionnaires. Height, sitting-height, hip and waist circumference were measured using standardised techniques.

Results: Urban and rural black South African women differed in their age at menarche (at ages 12.7 and 14.5 years, respectively). In urban women, a one-year increase in age at menarche was associated with a 0.65?cm and 0.16% increase in height and relative leg-length ratio, respectively. In both settings, earlier age at menarche and shorter relative leg-length were independently associated with an increase in waist circumference.

Conclusions: In black South African women, the earlier onset of puberty, and consequently an earlier growth cessation process, may lead to central fat mass accumulation in adulthood.     

Trends in weight,height, BMI and obesity in schoolchildren from Santa Rosa (Argentina), 1990–2005/07

Abstract

Aim: To assess secular changes in physical growth and the current prevalence and trend of overweight/obesity in Argentinian schoolchildren.

Subjects and methods: One thousand and forty-nine schoolchildren aged 6 and 12 years attending schools in 1990 were compared with an age-matched sample of 935 boys and girls collected between 2005–2007. Changes in weight, height and BMI by age between the surveys were analysed using one-way analysis of variance. Overweight and obesity were defined according to IOTF criteria and compared by Chi-squared test. Odds ratios (OR) and intervals of confidence (95% CI) were also calculated.

Results: Six and 12 year-old boys and girls were significantly heavier (1.2–3.2?kg) and had higher BMIs (0.7–1.0?kg/m²) in 2005–2007 than in 1990. Significant differences in height were seen in 6 year old boys (1.5?cm) and 12 year old girls (1.3?cm). Overweight and obesity increased by 4.4% (OR?=?1.4, 1.1–1.8) and 5.9% (OR?=?4.3, 2.8–6.5), respectively; obesity being higher in younger children.

Conclusion: The disharmonic secular change in weight and height has led to high overweight/obesity. The obesity increase is consistent with global and regional trends, indicating a shift in BMI distribution, especially at the higher centiles.     

Why is the body mass index calculated as mass/height2, not as mass/height3?

BACKGROUND: The body mass index or BMI, mass/height(2), is used to predict fatness and health. It is an approximation to the Benn index, mass/height(p), where p (typically 1.1-2.5 for adult populations) makes the index uncorrelated with height. Mass/height(3) is an index of body build that is independent of scale and statistics. AIM: To explain why p varies and is less than three, show how statistical methods can distort perceptions of mass-height relationships, and clarify the nature of the BMI. METHODS: A hypothetical adult population is modelled statistically, with mass being approximately proportional to height(3) and with neither variable determining the other. Values of p are calculated both for the model and for real adults. RESULTS: In both cases p increases with the correlation between mass and height. Both p and that correlation are usually lower for women than for men. CONCLUSIONS: In adult populations mass must vary more nearly with height(3) than with height(2), although, for reasons explained, conventional statistical techniques suggest otherwise. Nevertheless the BMI is a valid predictor of fatness from mass and height in adults and is properly divisible into fat mass and fat-free mass indices. The validity of the latter three indices for children is questionable.     

Consumption of milk,but not other dairy products,is associated with height among US preschool children in NHANES 1999–2002

Background: Little is known about how cow's milk consumption affects growth of young children.

Aim: The present study evaluated associations between milk consumption and height among preschool-age children in three ethnic groups in the USA.

Subjects and methods: A sample of 1002 children aged 24–59 months from NHANES 1999–2002 was used. Multivariate regression tested for associations between milk consumption (milk kJ/total kJ from 24 h recall, daily vs less frequent intake over 30 days) and height, controlling for age, sex, ethnicity, birth weight, and energy intake.

Results: Children in the highest quartile of milk intake (QIV) were taller (1.1–1.2 cm; p<0.01) than those in QII and QIII but not QI. Total calcium had a positive effect on height (p<0.01), but did not change the height differences among percentiles. Total protein was not associated with height and QIV children were taller (0.9–1.2 cm) than those in all other quartiles. Children who drank milk daily were taller (1.0 cm; p<0.02) than those with less frequent intake. Consumption of other dairy products (other dairy kJ/total kJ) had no association with height. Blacks were taller than Whites and Mexican-Americans; controlling for milk intake did not alter this pattern.

Conclusion: Milk contributes positively to height among preschool children; this association was not found for non-milk dairy products.     

Sitting height percentiles in 3–17-year-old Indian children: a multicentre study

Background: Sitting height (StH) percentiles are not described for the Indian paediatric population.

Aim: To generate multicentre StH percentile values for Indian children.

Subjects and methods: A total of 7961 apparently healthy children (3–17?years old, Boys: 4328) randomly selected from 10 schools from six states of India were measured for height (ht), StH and weight during July 2016–October 2017.

Results: The StH:Ht ratio was 0.52 (0.02) and was similar between boys and girls (p?>?0.1). The ratio decreased in boys until the age of 14?years and then slightly increased; the lowest ratio was observed during 13–15?years. In girls, however, the StH:Ht ratio decreased until the age of 9 years and then plateaued until 15?years of age with a slight increase at 16?years; the lowest ratio was observed at the age of 12–13?years. Sitting height percentiles (3rd, 10th, 25th, 50th, 75th, 90th and 97th) were computed using LMS chartmaker.

Conclusions: The results indicate that, during the pubertal years, the lower limb growth is more predominant than trunk growth. Further, this study provides smoothened percentile curves for sitting height in Indian children for the first time.     

Body mass index,waist-to-hip ratio and waist/height in adult population from Backa and Banat – the Republic of Serbia

Abstract

Background: Nutritional status is vital in the assessment of physical fitness and health status of populations.

Aim: This study aimed to describe relationships between BMI, waist-to-hip ratio (WHR) and waist/height (W/Ht) and factors such as education, residence, origin and ethnic belonging among adults in Backa and Banat.

Subjects and methods: The study was conducted in 47 villages in the north of Serbia. The tested group consisted of 4247 individuals, aged 20+.

Results: The problem of overweight and obesity was more common among men (66%) than women (49.71%). In the group with normal BMI, the majority of men and women were characterized by normal WHR and W/Ht values, but among them there were also groups with incorrect WHR (males ≥?0.95, females ≥?0.8) and W/Ht (≥?0.5). Socio-demographic factors had a little impact on BMI, WHR and W/Ht in men in certain age groups while their impact was higher in women. These factors, especially education and origin, had a significant impact on nutritional status in young and middle-aged women, whereas they were not significant in older female participants (>?60).

Conclusion: Despite the fact that this part of the country has undergone intensive social changes since the last decade of 20th century, the nutritional status of the population has not significantly changed.     

Children’s body fatness and prevalence of obesity in relation to height for age

Background: Children who are taller for their age tend to have higher BMI and, as a group, a greater prevalence of overweight/obesity.

Aim: To examine the relationship between height for age with three measures of adiposity.

Subjects and methods: Height, weight, BMI, % body fat (%BF) (by bioimpedance) and waist circumference (WC) were measured in 2298 Caucasian children (1251 boys) aged 4–14 years. Standard deviation scores (SDS) were derived and cases divided into quartiles of height SDS. Mean BMI, %BF and WC SDSs were compared across quartiles. Prevalence of overweight/obesity, over-fat/obesity and abdominal overweight/obesity within each height for age quartile was determined.

Results: Mean BMI, %BF and WC SDSs increased with increasing quartile of height SDS. Overweight/obesity, overfat/obesity and abdominal overweight/obesity prevalence increased from the first quartile (8.8–13%) to the fourth quartile (32.7–45.5%) of height SDS. A significant rising trend in mean SDSs for BMI, %BF and WC was also observed with increasing height SDS in overweight/obese children only.

Conclusion: A higher prevalence of excess weight, measured by BMI SDS among children taller for their age, is replicated when using %BF and WC. Height for age measurement has potential in screening children for later risk of obesity.     

Relationship between height,glucose intolerance,and hypertension in an urban African black adult population: a case for the "thrifty phenotype" hypothesis?

An association between the factors of low birth weight and fetal growth retardation and subsequent risk of cardiovascular disease has been proposed; this is the basis of the "thrifty phenotype" hypothesis described in relation to type 2 diabetes mellitus. The relationship between height, presumably an indicator of early life experience, and glucose intolerance and hypertension was examined in a sample survey of noncommunicable disease in an urban African adult population. Height, other anthropometric measurements, and biosocial data were obtained in the study of 998 civil servants selected by multistage sampling in Ibadan, a major Nigerian city. Ibadan is a low-prevalence region for diabetes, with a rate of 0.8% and 2.2% for an impaired glucose tolerance. The prevalence rate of hypertension was 10.3% in the population. A significant negative correlation was found between height and blood glucose level (r = -0.14, p < 0.001), whereas there was no correlation with blood pressures. Multiple regression analyses did not demonstrate height as a determinant of either blood pressure or plasma glucose. However, in a logistic model height was found to be associated with abnormal glucose tolerance (diabetes and impaired glucose tolerance) (odds ratio, 0.01; p < 0.003). In the logistic model of the blood pressure data there was no association between height and hypertension. There was some association between height and blood glucose level and also glucose intolerance in the urban African population sample, but none with elevated blood pressure. The significance of the observed inverse relationship, though uncertain, deserves further exploration.     

Changes in muscle contractile characteristics and jump height following 24 days of unilateral lower limb suspension

We measured changes in maximal voluntary and electrically evoked torque and rate of torque development because of limb unloading. We investigated whether these changes during single joint isometric muscle contractions were related to changes in jump performance involving dynamic muscle contractions and several joints. Six healthy male subjects (21 ± 1 years) underwent 3 weeks of unilateral lower limb suspension (ULLS) of the right limb. Plantar flexor and knee extensor maximal voluntary contraction (MVC) torque and maximal rate of torque development (MRTD), voluntary activation, and maximal triplet torque (thigh; 3 pulses at 300 Hz) were measured next to squat jump height before and after ULLS. MVC of plantar flexors and knee extensors (MVCke) and triplet torque decreased by 12% (P = 0.012), 21% (P = 0.001) and 11% (P = 0.016), respectively. Voluntary activation did not change (P = 0.192). Absolute MRTD during voluntary contractions decreased for plantar flexors (by 17%, P = 0.027) but not for knee extensors (P = 0.154). Absolute triplet MRTD decreased by 17% (P = 0.048). The reduction in MRTD disappeared following normalization to MVC. Jump height with the previously unloaded leg decreased significantly by 28%. No significant relationships were found between any muscle variable and jump height (r < 0.48), but decreases in torque were (triplet, r = 0.83, P = 0.04) or tended to be (MVCke r = 0.71, P = 0.11) related to decreases in jump height. Thus, reductions in isometric muscle torque following 3 weeks of limb unloading were significantly related to decreases in the more complex jump task, although torque in itself (without intervention) was not related to jump performance.     

Plateau–patella angle: An option for the evaluation of patellar height in patients with patellar instability

Background

Patellar instability is a debilitating disease. An important factor related to recurrent dislocation is patellar height. A new method of patellar height measurement, the plateau–patella angle (PPA), was proposed in 2011. However, to date, there is no study evaluating the use of this method in patients with patellar instability. The aim of this study was to evaluate the PPA in patients with recurrent patellar dislocation.

Cautious gait in relation to knowledge and vision of height: is altered visual information the dominant influence?

For some people, visual exposure creates difficulty with movement and balance, yet the mechanisms causing this are poorly understood. The altered visual environment is an obvious possible cause of degraded balance. We studied locomotion in normal healthy adults along a 22-cm-wide walkway at ground level and at a height of 3.5 m. This produced substantial changes in gait progression (velocity reduced by 0.34 ms(-1), P <0.01), proportion of time spent in double support more than doubled (P <0.01), and galvanic skin conductance, a measure of physiological arousal, increased significantly (P <0.01). Since increasing visual distance is known to destabilize balance, our primary question was whether the disturbing effects of height could be eliminated by replacing sight of the drop with a visual surround comparable to ground level while retaining the danger and knowledge of the risk. Removing visual exposure did not significantly change the gait progression (P = 0.65) or double support duration (P = 0.58) but produced a small, significant reduction in physiological arousal (P = 0.04). In response to postural threat, knowledge of danger rather than current visual environment was the dominant cause of cautious gait and elevated physiological arousal in response to postural threat. We conclude that the mechanisms disturbing locomotion, balance, and autonomic response occur at a high task level which integrates cognition and prior experience with sensory input.     

Does milk make children grow? relationships between milk consumption and height in NHANES 1999–2002

In the United States, milk (usually cow's milk) is widely considered an "essential food" to support bone growth among post-weaning age children, as evident in government-sponsored nutrition policies that mandate milk for children. Milk contains calories, protein, and calcium, among other nutrients, and bioactive components such as insulin-like growth factor-I (IGF-I), all of which may facilitate bone growth. There is a large literature on milk and/or calcium intake and its effects on bone density, but one aspect of bone mass--height--is not well studied in relation to milk consumption. Limited experimental studies show no consistent relationship across populations. To investigate this linkage among American children, analysis of the NHANES 1999-2002 was undertaken. NHANES data allow two hypotheses to be tested: (1) reported frequency of childhood milk consumption will be positively related to adult height and (2) height of children 5-18 years will be predicted by the reported frequency of milk consumption and/or milk intake from a 24-h dietary recall. Results indicate that adult height was positively associated with milk consumption at ages 5-12 and 13-17, after controlling for sex, education, and ethnicity. Among contemporary children, milk consumption had no effect on the height of 5-11 year olds after controlling for age, birthweight, energy intake, and ethnicity. In contrast, milk consumption frequency and milk intake (measured as grams of milk, or protein or calcium from milk) were significant predictors of the height of 12-18 year olds, along with age, sex, household income, and ethnicity. The greatest ethnic contrasts were between Mexican Americans and non-Hispanic whites and blacks, and milk variables remained significant predictors of height in these comparisons. Thus NHANES data show substantial variability in the effects of milk consumption on height.     

Nocardiosis in Quebec,Canada, 1988–2008

Nocardia is an uncommon pathogen, but immunosuppression, its main risk factor, is becoming more frequent. We aimed to evaluate changes in the annual incidence of nocardiosis and in the susceptibility profile of its aetiological agents. Demographic data were analysed for all isolates of Nocardia forwarded to the provincial public health laboratory of Quebec, Canada during the last two decades. Population incidence could be measured from 1997 onwards. Resistance patterns were analysed for those isolates selected for in vitro susceptibility testing. Throughout Quebec, 575 incident cases were identified between 1997 and 2008. The annual incidence of Nocardia infection/colonization increased from 0.33 (1997–1998) to 0.87 (2007–2008) per 100 000 inhabitants (p 0.001). In a small subset of patients for whom detailed clinical information was available, 59% of isolates corresponded to genuine infections. Nocardia farcinica predominated in specimens representing invasive infections (blood, brain, lung or pleural aspirates). Isolates were often non‐susceptible to several antimicrobials, with the exception of amikacin and linezolid. Overall, 43% of 157 isolates were non‐susceptible to trimethoprim–sulphamethoxazole. In conclusion, Nocardia infection/colonization remains rare. However, from 1997–1998, a progressive increase in incidence was noted in the province of Quebec. In regions such as ours, where a substantial proportion of invasive isolates are non‐susceptible in vitro to trimethoprim–sulphamethoxazole, the latter may no longer be the empirical treatment of choice in immunosuppressed and severely ill patients with nocardiosis.     

Reference charts of sitting height,leg length and body proportions for Chinese children aged 0–18 years

Background: The reference charts of sitting height (SH), subischial leg length (LL) and the sitting height/leg length ratio (SH/LL) are useful tools in assessing body proportion for clinicians and researchers in related areas. However, reference charts of body proportions for Chinese children and adolescents are limited.

Aim: To construct reference charts of SH, LL and SH/LL for Chinese children and adolescents.

Subjects and methods: Stature and sitting height of 92 494 (46 240 boys and 46 254 girls) healthy Han nationality children, aged 0–18 years, were measured in two national large-scale cross-sectional surveys in 2005 in China. SH/LL was selected as the indicator of body proportion. References of SH, LL and SH/LL were constructed using the LMS method.

Results: The reference charts demonstrated that SH and LL increased with age. Growth in SH slowed by the age of 17 years in boys and 15 years in girls. Similarly, growth in LL slowed at 16 years in boys and 14 years in girls. The SH/LL ratio declined from birth (2.00 in boys and 2.03 in girls) to 13 years in boys (1.11) and to 11 years in girls (1.13), then increased slightly to the age of 18 (1.16 in boys and 1.18 in girls). The gender difference of SH/LL was not significantly different before the age of 11 years. After the age of 11, SH/LL appeared elevated in girls compared to boys.

Conclusions: The reference charts of SH, LL and SH/LL are useful tools for assessing body proportions for Chinese children and adolescent individuals.     

β-adrenoreceptor activation in brain, lung and adipose tissue, measured by microdialysis in pig

PurposeThe aim of this study is to investigate the effect of local activation of β-adrenoreceptor by Isoprenaline on metabolism in brain, fat and lung measured by microdialysis.MethodsWe used 8 healthy pigs under general anaesthesia and placed microdialysis catheters in brain, fat, lung and artery. We performed a direct measurement of glucose, lactate, pyruvate and glycerol. The stimulation was performed by one-hour infusion of Isoprenaline, a β-adrenoreceptor agonist.ResultsThe infusion of isoprenaline did not affect the glucose in any tissue. The levels of lactate (p=0.008) and pyruvate (p=0.011) decreased significantly in lung after isoprenaline infusion. There was a significant increase in L/P ratio in fat tissue (p=0.001) while no significant changes could be found in brain (p=0.086) and lung (p=0.679).The most pronounced and significant change was observed in glycerol in fat (p<0.001) that increased by 95%.ConclusionThe prominent increase in glycerol in fat proved to be a good measure of β-adrenoreceptor activation and a measure of lipolysis. This can be used to online monitor β-adrenoreceptor activation by glycerol measurement in patients.     

Can history, ultrasound, or ELISA chlamydial antibodies, alone or in combination, predict tubal factor infertility in subfertile women?

BACKGROUND: This study aimed to determine whether medical history, transvaginal ultrasound (TVU) or Chlamydia trachomatis antibody testing (CAT), alone or in combination, could provide a non-invasive, clinically useful screening test for predicting tubal factor infertility (TFI) in subfertile women. METHODS: Prior to tubal evaluation, relevant medical history, TVU findings, and enzyme-linked immunosorbent assay (ELISA) IgG CAT results were collected. Sensitivity, specificity, likelihood ratios (LR) and accuracy for predicting TFI, as determined by laparoscopy and dye hydrotubation, were calculated for each test alone, and in parallel and series combination. RESULTS: Thirty per cent (63/207) were diagnosed with TFI. The highest sensitivity (67%, 95% CI: 54-77) included any positive test, yet missed one in three women with TFI. The highest specificity (100%, 95% CI: 97-100) required all three tests positive, but identified only three women. Only the combination of CAT and TVU rated as a good clinical test, but confidence intervals were wide due to the small numbers affected. The combination of CAT or TVU and CAT alone reported the highest accuracy (73%, 95% CI: 66-78), misdiagnosing one in four women. CONCLUSION: Medical history, TVU appearances, and ELISA IgG CAT alone, or in combination, failed to predict accurately TFI in subfertile women.