Family migration and physical growth in Merida, Yucatan, Mexico

Phlebotomine sand flies in rural Mayan communities of Southern Mexico: The heterogeneity of the ruralscape increases the entomological risk

In the Yucatan Peninsula, tropical preserved forests harbor a high diversity of phlebotomine sand fly species, potential vectors of Leishmania. As a result, a significant risk of contracting localized cutaneous leishmaniasis (LCL) is associated with entry into these forest ecosystems. However, with the current trajectory of land use in the region, communities now live within modified landscapes which could increase their risk of contact with vectors. In this study, we characterized the sand fly fauna and its relationship with the characteristics of peridomestic habitats in two rural communities in Yucatan characterized by contrasting records of leishmaniasis. Five human dwellings in each community were randomly selected and the peridomestic landscape was characterized (i.e., type and percentage of land use). For the collection of sand flies, CDC traps were deployed in both the intra and peridomicile. Differences in alpha and beta diversity between communities and ecotopes were estimated considering three separate groups, all species together, zoophilic species, and anthropophilic species. In total, 1, 241 sand flies represented by eight species were collected from November 2021-March 2022. Both communities registered the presence of sand flies in the intra and peridomicile, and females were more abundant than males. However, the greatest diversity of species was recorded in the peridomicile of the community with the highest composition of land uses. Our study demonstrates that the transformation of the forest around the communities favors the abundance and richness of sand flies in the peridomestic environment. We discuss the limitations and implications of our findings regarding the potential risk of the emergence of peri‑rural cycles of leishmaniasis in the region.

Preece-Baines Model 1 to Estimate Height and Knee Height Growth in Boys and Girls From Merida, Mexico

Background:

Height and body segments in children have differential pubertal growth characteristics. Lower leg length is a sensitive indicator of child’s nutritional status.

Objective:

The purpose of this study was to estimate differential timing and tempo of height and knee height (KH) growth in 9- to 17-year-old boys (n = 475) and girls (n = 500) from Merida, Mexico.

Methods:

In this cross-sectional study, the Preece-Baines growth curves—model 1 (PB 1) was fitted to the anthropometric data for height and KH.

Results:

Based on the PB 1 model, KH had earlier age at maximum increment than height in boys (height = 12.37 years, KH = 11.54 years) and girls (height = 11.01 years, KH = 10.93 years). Peak velocity of these 2 dimensions was different in both sexes (boys: height = 7.11 cm/yr, KH = 2.25 cm/yr; girls: height = 5.14 cm/yr, KH = 1.45 cm/yr). Differences ( P <.001) by sex were also observed for the estimated size at peak velocity and final size of height and KH.

Conclusions:

When compared to height, KH was shown to have earlier adolescent growth spurt and a smaller difference between final size and the size at maximum (peak) velocity indicating an earlier age for achieving adult size. Overall, the studied boys and girls had short estimated final size, an earlier age at maximum increment, and a lower peak velocity in height than urban Guatemalan peers, the only regional reference available.

Maternal height and its relationship to offspring birth weight and adiposity in 6- to 10-year-old Maya children from poor neighborhoods in Merida, Yucatan

OBJECTIVE

To analyze the relationship between maternal height, offspring birth weight, and adiposity at 6-10 years of age in a sample of 197 mother-child dyads from Merida, Mexico.

MATERIALS AND METHODS

During 2008-2009 and 2011-2013, measurements were taken of maternal height and weight; and height, waist circumference (WC), and skinfolds (triceps, subscapular, and suprailiac) of their children. Participant body composition was estimated using a bioelectrical impedance analyzer. A questionnaire was applied to document household socioeconomic conditions. Multiple linear regression models were used to study the association between maternal height, offspring birth weight and fat mass index (FMI), WC, and sum of skinfolds (SumSkfZ) in boys and girls, separately.

RESULTS

After adjusting for child age and household socioeconomic conditions, maternal height was identified to be significantly associated (p < .05) with FMI, WC, and SumSkf only in boys. In all models, child adiposity was inversely related to maternal height. Offspring birth weight was not associated with any adiposity parameter.

DISCUSSION

The results suggest that maternal nutritional history as reflected in short maternal stature is associated with higher body fat in children, and that male offspring are more vulnerable to intergenerational influences.

CHILD GROWTH: CONCEPT ANALYSIS

ABSTRACT The aim of this study was to analyze the concept of child growth by identifying the attributes and consequences that make up the phenomenon. The concept analysis was supported by 41 studies and based on the evolutionary analysis model and integrative literature review. Five databases, Scopus, CINAHL, LILACS, PubMed, and the Cochrane Library were searched to select articles. The search found that growth has presented different connotations, including social and physiological aspects, which are part of the physical domain of child development. Attributes, antecedents, and consequences identified provide an overview of the phenomenon analyzed, because these point out several aspects previously related to other studies on child growth. The theoretical understanding about child growth can offer nurses in-depth knowledge about factors involved in this process, facilitating intervention-based decision-making.

Intergenerational influences on the growth of Maya children: The effect of living conditions experienced by mothers and maternal grandmothers during their childhood

OBJECTIVES

To test the hypothesis that living conditions experienced by maternal grandmothers (F1 generation) and mothers (F2 generation) during their childhood are related to height and leg length (LL: height - sitting height) of their 6-to-8 year old children (F3 generation).

METHODS

From September 2011 to June 2012 we obtained height and LL, and calculated z-score values of these measurements for 109 triads (F1 , F2 , F3 ) who are Maya living in Merida, Yucatan, Mexico. Multiple regression models were adjusted to examine the relation of anthropometric and intergenerational socioeconomic parameters of F1 (house index and family size during childhood) and F2 (paternal job loss during childhood) with the z-score values of height and LL of F3 .

RESULTS

Children's height and LL were positively associated with maternal height and LL. This association was relatively stronger in LL. Better categories of grand-maternal house index were significantly associated with higher values of height and LL in grandchildren. Grand-maternal family size was positively related with LL, but not with height.

CONCLUSIONS

Our findings partially support the hypothesis that living conditions experienced by recent maternal ancestors (F1 and F2 ) during their growth period influence the growth of descendants (F3 ). Results suggest that LL is more sensitive to intergenerational influences than is total height and that the transition from a traditional rural lifestyle to urban conditions results in new exposures for risk in human physical growth.

Body fatness in relation to physical activity and selected socioeconomic parameters of adolescents aged 15-17 years in Merida, Yucatan

BACKGROUND

Increasing rates of overweight and obesity in adolescents are major concerns in many countries, including Mexico.

OBJECTIVES

To study anthropometric and body composition characteristics (BCC) and their relations with socioeconomic status (SES), biological history and physical activity (PA) of school-going adolescent boys and girls in the city of Merida, Yucatan, Mexico.

SUBJECTS AND METHODS

In this cross-sectional study, a sample of 321 adolescents (156 boys and 165 girls) aged 15-17 years from public and private schools in Merida, was taken from a study carried out in 2008-2009.

RESULTS

Body mass index had significant correlations to BCC (fat mass and fat-free mass). The rate of stunting was higher in girls (18.20%) than in boys (7.69%). Stunted adolescents had higher body fat (%) than normally growing peers. High rates of overweight (boys 26.28%, girls 24.24%) and obesity (boys 10.26%, girls 6.06%) were recorded. SES (parents' age, education and occupation; crowding index in the family; household food expenditure), participants' biological history and PA are related with height and BCC by age and sex.

CONCLUSION

Adolescents with excess weight (overweight + obesity) reported being less physically active. SES and PA were strongly related to growth and body fatness in the studied adolescents.

A qualitative case study of child protection issues in the Indian construction industry: investigating the security, health, and interrelated rights of migrant families

BACKGROUND

Many of India's estimated 40 million migrant workers in the construction industry migrate with their children. Though India is undergoing rapid economic growth, numerous child protection issues remain. Migrant workers and their children face serious threats to their health, safety, and well-being. We examined risk and protective factors influencing the basic rights and protections of children and families living and working at a construction site outside Delhi.

METHODS

Using case study methods and a rights-based model of child protection, the SAFE model, we triangulated data from in-depth interviews with stakeholders on and near the site (including employees, middlemen, and managers); 14 participants, interviews with child protection and corporate policy experts in greater Delhi (8 participants), and focus group discussions (FGD) with workers (4 FGDs, 25 members) and their children (2 FGDs, 9 members).

RESULTS

Analyses illuminated complex and interrelated stressors characterizing the health and well-being of migrant workers and their children in urban settings. These included limited access to healthcare, few educational opportunities, piecemeal wages, and unsafe or unsanitary living and working conditions. Analyses also identified both protective and potentially dangerous survival strategies, such as child labor, undertaken by migrant families in the face of these challenges.

CONCLUSIONS

By exploring the risks faced by migrant workers and their children in the urban construction industry in India, we illustrate the alarming implications for their health, safety, livelihoods, and development. Our findings, illuminated through the SAFE model, call attention to the need for enhanced systems of corporate and government accountability as well as the implementation of holistic child-focused and child-friendly policies and programs in order to ensure the rights and protection of this hyper-mobile, and often invisible, population.

Nutritional status of Maya children, their mothers, and their grandmothers residing in the City of Merida, Mexico: revisiting the leg-length hypothesis

OBJECTIVES

To test the hypothesis that leg length-relative-to-stature is a more sensitive indicator of nutrition and health than is total height (HT) or sitting height (SH) in a sample of 109 triads of urban Maya children (6.0-8.99 years), their mothers, and maternal grandmothers from Merida, Mexico.

METHODS

From September 2011 to June 2012, the following factors were obtained from all participants: (1) HT, SH, and leg length (LL); (2) the sitting height ratio (SHR = [SH × 100]/HT), relative leg length index (RLLI = [LL × 100]/height), and percentiles and z-scores of HT, SH, and LL were calculated; and (3) the percentages of stunting for children or very short ZHT for the adults, short ZSH, and short ZLL: HT-for-age, SH-for-age, or LL-for-age below the 5th percentile of the reference were calculated. Correlations were performed to examine the association between z-scores of HT, SH, and LL among three generations.

RESULTS

Stunting in children was 11% (short ZLL = 29%, short ZSH = 7%). Short ZHT was present in 71% of mothers (short ZLL = 54%, short ZSH = 50%) and 90% of grandmothers (short ZLL = 69%, short ZSH = 83%). Significant correlations in ZHT, ZSH, and ZLL were found in mother-to-child and grandmother-to-mother, with the strongest correlations for ZLL.

CONCLUSIONS

These findings support the hypothesis for children and mothers. Based on ZLL, there is evidence that childhood and nutrition have improved somewhat for each younger generation. Persistent environmental adversity during growth resulted in growth deficits for LL and SH for the mothers and grandmothers.

Fat free mass explains the relationship between stunting and energy expenditure in urban Mexican Maya children

BACKGROUND

Childhood stunting has been associated with an increased risk of obesity in adulthood, but the causes are unclear. This study hypothesizes that stunting significantly reduces both resting and activity energy expenditure.

AIM

To assess and describe energy expenditure of low socio-economic Maya children and to determine whether stunting is independently related to energy expenditure after controlling for lean mass.

SUBJECTS AND METHODS

Thirty-three urban Maya children, 17 boys, aged 7-9 years, living in Merida, Mexico, were measured for height, weight and bioelectrical impedance analysis (BIA). Body composition was estimated from BIA. Energy expenditure was measured for one week using the Actiheart (combined heart rate and accelerometer).

RESULTS

Stunting (height-for-age below the 5(th) percentile of NHANES III based references) affected 35% of these physically active children. Using multiple linear regression analysis, greater lean body mass predicted higher resting and activity energy expenditure. Stature was not a significant predictor of resting energy expenditure. A lower height-for-age z-score, but not stunting as a categorical variable, significantly predicted lower activity energy expenditure.

CONCLUSION

The hypothesis that stunting reduces total energy expenditure (resting + active) in children is not supported. Rather, children with shorter stature and less lean body mass have lower total energy expenditure. Complex interactions between body size, body composition, and metabolic activity appear to elevate the risk for later life obesity in these Maya children.

Estimation of stature from upper arm length in children aged 4.0 to 6.92 y in Merida, Yucatan

OBJECTIVE

To understand age-sex variation of stature and upper arm length (UAL) and to estimate stature from UAL through prediction equations.

METHODS

A cross-sectional study was undertaken in 2006-2007 among 458 children (218 boys and 240 girls) aged 4.0 to 6.92 y of south Merida in Yucatan, Mexico.

RESULTS

The results show significant age variation (p < 0.001) of stature and upper arm length (UAL) in children. Boys show significantly higher mean stature and UAL compared to the girls. Relative proportion of upper arm length to stature is greater in boys. Interrelationship between stature and upper arm length exhibits significant association with respect to age and sex of children. Reconstruction of stature from upper arm length through regression analysis also gives good prediction models for separate and combined samples of both sexes with age. Regression coefficients for UAL predicting stature account for 0.90 or greater variance in the dependent variable (stature). The difference between reconstructed stature and the actual measurement is less than ±2.00 cm.

CONCLUSIONS

UAL appears to be a reliable indicator to estimate stature in children aged 4.0 to 6.92 y old.

Changes in stature, weight, and nutritional status with tourism-based economic development in the Yucatan

Over the past 40 years, tourism-based economic development has transformed social and economic conditions in the Yucatan Peninsula, Mexico. We address how these changes have influenced anthropometric indicators of growth and nutritional status in Yalcoba, a Mayan farming community involved in the circular migration of labor in the tourist economy. Data are presented on stature and weight for children measured in 1938 in the Yucatan Peninsula and from 1987 to 1998 in the Mayan community of Yalcoba. In addition, stature, weight and BMI are presented for adults in Yalcoba based on clinic records. Childhood stature varied little between 1938 and 1987. Between 1987 and 1998 average male child statures increased by 2.6cm and female child statures increased by 2.7cm. Yet, 65% of children were short for their ages. Between 1987 and 1998, average child weight increased by 1.8kg. Child BMIs were similar to US reference values and 13% were considered to be above average for weight. Forty percent of adult males and 64% of females were overweight or obese. The anthropometric data from Yalcoba suggest a pattern of stunted children growing into overweight adults. This pattern is found elsewhere in the Yucatan and in much of the developing world where populations have experienced a nutrition transition toward western diets and reduced physical activity levels.