Cognitive and socio-emotional correlates of psychological well-being and mental health in Guatemalan adults

BACKGROUND

Little is known about associations of psychological and mental well-being with cognitive and socioemotional factors in low and middle-income countries, particularly among vulnerable populations born in adverse environments that may restrict developmental potential. This study aimed to examine the cognitive and socioemotional correlates of psychological well-being and mental health in a cohort of Guatemalan adults born in contexts of poverty and malnutrition.

METHODS

From Dec 2017 to Apr 2019, data were collected from 704 women and 564 men ages 40-57 years living in four rural villages in eastern Guatemala and Guatemala City. We measured latent domains of psychological well-being, spirituality and religion, emotional support, and executive function using Confirmatory Factor Analysis (CFA). Under a Structural Equation Modeling framework, we examined intercorrelations among latent domains and observed measures of intelligence and mental health.

RESULTS

CFA supported the construct validity of factor structures in this population. Correlations of psychological well-being with spirituality and religion were moderate in women (r = 0.68, p < 0.001) and men (r = 0.70, p < 0.001). Executive function was weakly correlated with psychological well-being in men (r = 0.23, p < 0.001) and showed no association in women. Correlations of psychological well-being with emotional support and IQ were weak in women (r = 0.34, and r = 0.15, respectively; p < 0.001 for both) and men (r = 0.35, and r = 0.25, respectively; p < 0.001 for both). Mental health and IQ were weakly correlated in men (r = 0.09, p < 0.05) and showed no association in women. Mental health showed weak correlations with emotional support (r = 0.18, p < 0.001 in women; r = 0.09, p < 0.05 in men), psychological well-being (r = 0.32 and r = 0.35, in women and men respectively; p < 0.001 for both) and showed no association with executive function in both sexes.

CONCLUSIONS

Of all examined factors, spirituality and religion made the greatest contribution to psychological well-being. These findings support the notion that in populations experiencing difficult circumstances, religion can perhaps make a greater contribution to well-being and aid coping. More research is needed to examine mediators of this association.

Influence of enhanced nutrition and psychosocial stimulation in early childhood on cognitive functioning and psychological well-being in Guatemalan adults

Rationale

Early-life nutrition interventions in low and middle-income countries have demonstrated long-term benefits on cognitive skills, however, their influence on socioemotional outcomes has not been fully explored. Moreover, the mediating processes through which nutrition intervention effects operate and are maintained over time are understudied.

Methods

We followed-up a cohort of Guatemalan adults who participated as children in a community randomized food-supplementation trial. We examined associations of exposure to nutritional supplementation from conception to age 2 years with executive function (measured using three sub-tests of the NIH Toolbox Cognition Battery) and psychological well-being (measured using two sub-scales of the NIH Toolbox Emotion Battery) at ages 40–57 years (n = 1268). We used structural equation modeling to investigate the mediating role of psychosocial stimulation (measured in childhood using parent reports and ratings of home environments), cognitive ability (measured at ages 26–42 years using standardized tests), and executive function on the association of early-life exposure to nutritional supplementation with adult psychological well-being (n = 1640).

Results

We found positive but inconsistent associations of nutritional supplementation in childhood with executive function and psychological well-being in adulthood. Psychosocial stimulation, cognitive ability, and executive function did not mediate the association of early-life nutritional supplementation with adult psychological well-being. We found strong and positive associations of psychosocial stimulation in childhood with cognitive ability, executive function, and psychological well-being in adulthood. Moreover, we observed no interaction of exposure to nutritional supplementation and psychosocial stimulation in childhood with cognitive and psychological well-being outcomes in adulthood.

Conclusion

Our findings suggest that childhood nutrition interventions have long-lasting effects on cognitive ability and psychological well-being outcomes.

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We assess the influence of early-life nutrition on neurodevelopmental outcomes.

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We use a theoretical approach to examine mediators of the association.

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We found no mediators of the association of early-life nutrition with adult psychological well-being.

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Psychosocial stimulation is strongly associated with neurodevelopmental outcomes.

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Improved child nutrition is positively associated with adult psychological well-being.

Social and Economic Development and Change in 4 Guatemalan Villages Over a Half Century

This article describes nearly 50 years of social and economic development and changes that have occurred in the 4 villages of the Institute of Nutrition of Central America and Panama (INCAP) Longitudinal Study (1969-1977). In doing so, it contextualizes the changes in health and nutrition for the study population over that period. Since the start of the INCAP Longitudinal Study, the original 4 villages, like their home country, have undergone tremendous demographic, social, and economic change. Originally rather isolated, road and transportation access for the villages has improved steadily and substantially. The population in the villages has more than doubled. Schooling access and outcomes have also improved substantially, with average grades of schooling tripling and literacy doubling, reaching levels currently on par with national averages. Occupations have also changed over the course of a generation. Early on, subsistence farming and agriculture in general were dominant but are now much less common. Much of this change is associated with declining agricultural markets alongside increased access to nonagricultural jobs near the villages and in the capital. With all these changes have come improvements in living standards. It is within this dynamic context that study participants for the INCAP Longitudinal Study were born and raised and where most now live as adults.

Demographic and Socio-Economic Changes in Families in Four Guatemalan Villages, 1967–1987

The Institute of Nutrition of Central America and Panama (INCAP) carried out a longitudinal study of the effects of nutritional improvements on growth and development in early childhood in four villages in eastern Guatemala, 1969–1977, with a preparatory survey in 1967 and a follow-up study of the participants in 19881989. This paper examines differences among the four villages in education, occupation, quality of housing, and demographic profiles over a 20-year period, focusing on comparisons between the two villages that received a high-energy, high-protein supplement and the two that received a low-energy supplement at two different times: before the initial longitudinal study and before the follow-up study. The results suggest gradual improvement in all the villages on a number of indicators. However, the two pairs of village were not comparable on all measures; of particular concern for the interpretation of effects on cognitive development are differences in education.

Secular Trends in Adult and Child Anthropometry in Four Guatemalan Villages

Secular trends in the stature and head circumference of adults born between 1905 and 1959 and in the length of three-year-old children born between 1965 and 1985 from four villages of eastern Guatemala are analysed. Data were collected before (1968), during (1969–1977), and after (1988) a longitudinal protein-energy supplementation trial conducted in the four villages. No secular trends are observed in the age-adjusted height or the head circumference of the adults studied; similar results are obtained whether a longitudinal or a cross-sectional method is used to correct height for the effects of ageing. A positive and significant linear trend is observed in the length of the three-year-olds. The estimated increase of 2.5–3.3 cm seen over this 20-year period represents only approximately 27% of the total deficit in length seen in these children in 1968 (11 cm).

Overview of Long-Term Nutrition Intervention Studies in Guatemala, 1968–1989

This is an overview of ten papers published in this issue of the Food and Nutrition Bulletin dealing with two components of a nutrition intervention study: the INCAP longitudinal study, 1969–1977, and the follow-up study, 1988–1989. The latter is a continuation of the former and seeks to test the hypothesis that nutritional improvements in early childhood lead to improved human capital formation in adolescents and young adults. Beneficial outcomes have been found to include greater body size and fat-free mass (particularly in females), improved working capacity in males, and enhanced intellectual performance in bath sexes.

Schooling, Educational Achievement, and Cognitive Functioning among Young Guatemalan Adults

Quantity and quality of schooling obtained and the resulting skills and knowledge acquired are important components of human capital. We describe the distribution of selected measures of schooling, educational achievement, and cognitive functioning among individuals who participated as children in a nutrition supplementation trial in Guatemala and were followed up in 2002–04. Among 1,469 respondents (response rate 80%), who were 26–41 years of age in 2003, more than 90% of men and women had attended at least some school; more than half of men and more than one-third of women had completed sixth grade. Schooling attainment of both men and women has increased across birth cohorts but the schooling gap between men and women has increased. Parental socioeconomic status, as measured in 1975, is a strong predictor of schooling attainment. Basic literacy is high among those studied, with more than 80% able to read simple sentences. The gap in educational achievement favoring men narrowed across birth cohorts due to increases among younger women. The greater performance among men on the Raven's Progressive Matrices test persisted despite increased scores in the younger birth cohorts for both men and women. Migrants to Guatemala City have completed more years of school and scored higher on the tests of educational achievement and cognitive functioning than have cohort members who have remained in the study villages.

Social and Economic Development and Change in four Guatemalan Villages: Demographics, Schooling, Occupation, and Assets

This article uses census data and village histories to examine changes over the last 35 years in the four villages where the Institute of Nutrition of Central America and Panama (INCAP) Longitudinal Study (1969–77) was conducted and offers a rare picture of development and change in rural localities over a long period of time. In addition, by characterizing the environment in which the subjects of this study were raised, we provide context for and inputs into quantitative analyses of data collected at various points in time on these subjects. The villages have undergone massive demographic, social, and economic change. Initial differences have conditioned many of these changes, especially differences associated with agricultural potential and location. Originally these villages were rather isolated, but road and transportation access has improved substantially. The populations in the villages have more than doubled and also have aged. While marriage patterns have held steady, religious practice has changed a great deal. After many years of steady out-migration, three of the four villages are more recently experiencing net in-migration, a pattern associated with ease of access. Schooling access and outcomes also have improved, with average grades of schooling nearly tripling and literacy doubling to levels currently above national averages. Although agriculture remains an important component of individual livelihood strategies, non-agricultural sources of employment have become more important. Much of this change is associated with declining agricultural markets and increased access to non-agricultural jobs near the villages and in the capital. Accompanying these changes has been an improvement in living standards as measured by a number of indicators of household living conditions and consumer durable goods.

Parental Resources, Schooling Achievements, and Gender Schooling Gaps: Evidence of Change over 25 years in Rural Guatemala

We use village census data and linear regression models to examine changes between 1975 and 2002 in the associations of parental resources with boys' and girls' schooling in four rural Guatemalan villages. Levels of schooling in 1975 were universally low for children 7-17 years. Large increases in schooling achievements occurred between 1975 and 2002. By 2002, schooling levels were comparable for younger boys and girls (7-12 years, N = 3,525) and favored older boys compared to older girls (13-17 years, N = 2,440) by about 0.5 grades. The associations of household standard of living and maternal schooling with schooling among girls diminished over time and became more comparable with these associations among boys, and the associations of household standard of living with schooling among older boys declined and became more comparable with these associations among girls. Thus, as increased social investments reduce the costs of schooling or increase the supply and quality of schooling to families, the magnitudes of the associations between parental resources and children's schooling decline and become more gender equitable at all ages. However, our results show that older boys may benefit more than older girls from social investments in schooling. These changes suggest potential needs to monitor gender gaps in schooling retention among older children, to insure gender equitable access to social investments in schooling, and to encourage parents to invest in schooling as joint measures to achieve greater schooling achievements of girls and boys.

Childhood nutrition and later fertility: pathways through education and pre-pregnant nutritional status

Better childhood nutrition is associated with earlier physical maturation during adolescence and increased schooling attainment. However, as earlier onset of puberty and increased schooling can have opposing effects on fertility, the net effect of improvements in childhood nutrition on a woman's fertility are uncertain. Using path analysis, we estimate the strength of the pathways between childhood growth and subsequent fertility outcomes in Guatemalan women studied prospectively since birth. Height for age z score at 24 months was positively related to body mass index (BMI kg/m2) and height (cm) in adolescence and to schooling attainment. BMI was negatively associated (-0.23 +/- 0.09 years per kg/m2; p < .05) and schooling was positively associated (0.38 +/- 0.06 years per grade; p < .001) with age at first birth. Total associations with the number of children born were positive from BMI (0.07 +/- 0.02 per kg/m2; p < .05) and negative from schooling (-0.18 +/- 0.02 per grade; p < .01). Height was not related to age at first birth or the number of children born. Taken together, childhood nutrition, as reflected by height at 2 years, was positively associated with delayed age at first birth and fewer children born. If schooling is available for girls, increased growth during childhood will most likely result in a net decrease infertility.

Individual capital and cognitive ageing in Guatemala

Using data from adults 50 years and older in Guatemala (N = 643), we assessed to what extent measures of individual capital-economic, social, intellectual, and biological-were associated with and account for variation in cognitive functioning, as measured by the Modified Mini-Mental Status Exam (M-MMSE). Measures of these components of individual capital are positively associated with cognitive functioning, and together with other attributes, account for 29.6 per cent of its variance. Schooling accounts for the largest unique share (5.3 per cent) of the variance, followed by household standard of living (2.0 per cent), church attendance (1.3 per cent), and z-score for height (0.9 per cent). In a setting like Guatemala-with low schooling, widespread poverty, malnutrition, and infectious disease-early life investments that increase schooling and improve nutrition may be valuable as investments to mitigate cognitive impairment in older adults and its contribution to the disease burden.