Postweaning exposure to aflatoxin results in impaired child growth: a longitudinal study in Benin, West Africa

Aflatoxins are dietary contaminants that are hepatocarcinogenic and immunotoxic and cause growth retardation in animals, but there is little evidence concerning the latter two parameters in exposed human populations. Aflatoxin exposure of West African children is known to be high, so we conducted a longitudinal study over an 8-month period in Benin to assess the effects of exposure on growth. Two hundred children 16-37 months of age were recruited from four villages, two with high and two with low aflatoxin exposure (50 children per village). Serum aflatoxin-albumin (AF-alb) adducts, anthropometric parameters, information on food consumption, and various demographic data were measured at recruitment (February) and at two subsequent time points (June and October). Plasma levels of vitamin A and zinc were also measured. AF-alb adducts increased markedly between February and October in three of the four villages, with the largest increases in the villages with higher exposures. Children who were fully weaned at recruitment had higher AF-alb than did those still partially breast-fed (p < 0.0001); the major weaning food was a maize-based porridge. There was no association between AF-alb and micronutrient levels, suggesting that aflatoxin exposure was not accompanied by a general nutritional deficiency. There was, however, a strong negative correlation (p < 0.0001) between AF-alb and height increase over the 8-month follow-up after adjustment for age, sex, height at recruitment, socioeconomic status, village, and weaning status; the highest quartile of AF-alb was associated with a mean 1.7 cm reduction in growth over 8 months compared with the lowest quartile. This study emphasizes the association between aflatoxin and stunting, although the underlying mechanisms remain unclear. Aflatoxin exposure during the weaning period may be critical in terms of adverse health effects in West African children, and intervention measures to reduce exposure merit investigation.

Cross-sectional and longitudinal epidemiological studies of Internet gaming disorder: A systematic review of the literature

AIM

The diagnostic criteria of Internet gaming disorder (IGD) have been included in section III of DSM-5. This study aims to systematically review both cross-sectional and longitudinal epidemiological studies of IGD.

METHODS

All publications included in PubMed and PsychINFO up to May 2016 were systematically searched to identify cross-sectional studies on prevalence and longitudinal studies of IGD. In the process of identification, articles in non-English languages and studies focusing solely on the use of gaming were excluded, and those meeting the methodological requirements set by this review were included. As a result, 37 cross-sectional and 13 longitudinal studies were selected for review.

RESULTS

The prevalence of IGD in the total samples ranged from 0.7% to 27.5%. The prevalence was higher among males than females in the vast majority of studies and tended to be higher among younger rather than older people in some studies. Geographical region made little difference to prevalence. Factors associated with IGD were reported in 28 of 37 cross-sectional studies. These were diverse and covered gaming, demographic and familial factors, interpersonal relations, social and school functioning, personality, psychiatric comorbidity, and physical health conditions. Longitudinal studies identified risk and protective factors, and health and social consequences of IGD. The natural course of IGD was diverse but tended to be more stable among adolescents compared to adults.

CONCLUSION

Although existing epidemiological studies have provided useful data, differences in methodologies make it difficult to compare the findings of these studies when drawing consensus. Future international studies using reliable and uniform methods are warranted.

Increased turnover of T lymphocytes in HIV-1 infection and its reduction by antiretroviral therapy

The mechanism of CD4(+) T cell depletion in human immunodeficiency virus (HIV)-1 infection remains controversial. Using deuterated glucose to label the DNA of proliferating cells in vivo, we studied T cell dynamics in four normal subjects and seven HIV-1-infected patients naive to antiretroviral drugs. The results were analyzed using a newly developed mathematical model to determine fractional rates of lymphocyte proliferation and death. In CD4(+) T cells, mean proliferation and death rates were elevated by 6.3- and 2.9-fold, respectively, in infected patients compared with normal controls. In CD8(+) T cells, the mean proliferation rate was 7.7-fold higher in HIV-1 infection, but the mean death rate was not significantly increased. Five of the infected patients underwent subsequent deuterated glucose labeling studies after initiating antiretroviral therapy. The lymphocyte proliferation and death rates in both CD4(+) and CD8(+) cell populations were substantially reduced by 5-11 weeks and nearly normal by one year. Taken together, these new findings strongly indicate that CD4(+) lymphocyte depletion seen in AIDS is primarily a consequence of increased cellular destruction, not decreased cellular production.

Hierarchical linear modeling analyses of the NEO-PI-R scales in the Baltimore Longitudinal Study of Aging

The authors examined age trends in the 5 factors and 30 facets assessed by the Revised NEO Personality Inventory in Baltimore Longitudinal Study of Aging data (N=1,944; 5,027 assessments) collected between 1989 and 2004. Consistent with cross-sectional results, hierarchical linear modeling analyses showed gradual personality changes in adulthood: a decline in Neuroticism up to age 80, stability and then decline in Extraversion, decline in Openness, increase in Agreeableness, and increase in Conscientiousness up to age 70. Some facets showed different curves from the factor they define. Birth cohort effects were modest, and there were no consistent Gender x Age interactions. Significant nonnormative changes were found for all 5 factors; they were not explained by attrition but might be due to genetic factors, disease, or life experience.

Picky eating during childhood: a longitudinal study to age 11 years

Picky eating is a common disorder during childhood often causing considerable parental anxiety. This study examined the incidence, point prevalence, persistence and characteristics of picky eating in a prospective study of 120 children and their parents followed from 2 to 11 years. At any given age between 13% and 22% of the children were reported to be picky eaters. Incidence declined over time whereas point prevalence increased indicating that picky eating is often a chronic problem with 40% having a duration of more than 2 years. Those with longer duration differed from those with short duration having more strong likes and dislikes of food and not accepting new foods. Parents of picky eaters were more likely to report that their children consumed a limited variety of foods, required food prepared in specific ways, expressed stronger likes and dislikes for food, and threw tantrums when denied foods. They were also more likely to report struggles over feeding, preparing special meals, and commenting on their child's eating. Hence, picky eating is a prevalent concern of parents and may remain so through childhood. It appears to be a relatively stable trait reflecting an individual eating style. However no significant effects on growth were observed.

Timing of the decline in physical activity in childhood and adolescence: Gateshead Millennium Cohort Study

Background and aim

There is a widely held and influential view that physical activity begins to decline at adolescence. This study aimed to identify the timing of changes in physical activity during childhood and adolescence.

Methods

Longitudinal cohort study (Gateshead Millennium Study) with 8 years of follow-up, from North-East England. Cohort members comprise a socioeconomically representative sample studied at ages 7, 9, 12 and 15 years; 545 individuals provided physical activity data at two or more time points. Habitual total volume of physical activity and moderate-to-vigorous intensity physical activity (MVPA) were quantified objectively using the Actigraph accelerometer over 5–7 days at the four time points. Linear mixed models identified the timing of changes in physical activity across the 8-year period, and trajectory analysis was used to identify subgroups with distinct patterns of age-related changes.

Results

Four trajectories of change in total volume of physical activity were identified representing 100% of all participants: all trajectories declined from age 7 years. There was no evidence that physical activity decline began at adolescence, or that adolescent declines in physical activity were substantially greater than the declines during childhood, or greater in girls than boys. One group (19% of boys) had relatively high MVPA which remained stable between ages 7 and15 years.

Conclusions

Future policy and research efforts to promote physical activity should begin well before adolescence, and should include both boys and girls.

Long COVID in the Faroe Islands - a longitudinal study among non-hospitalized patients

Background

Little is known about long-term recovery from COVID-19 disease, especially in non-hospitalized individuals. In this longitudinal study we present symptoms registered during the acute phase as well as long COVID, i.e. long-lasting COVID-19 symptoms, in patients from the Faroe Islands.

Methods

All consecutive patients with confirmed RT-PCR testing from April to June 2020 were invited to participate in this study for the assessment of long COVID. Demographic and clinical characteristics and self-reported acute and persistent symptoms were assessed using a standardized detailed questionnaire administered at enrollment and at repeated phone interviews in the period 22 ^th April to Aug 16 ^th.

Results

Of the 180 participants (96.3% of the 187 eligible COVID-19 patients), 53.1% reported persistence of at least one symptom after a mean of 125 days after symptoms onset, 33.3% reported one or two symptoms and 19.4% three or more symptoms. At the last follow-up, 46.7% were asymptomatic compared with 4.4 % during the acute phase. The most prevalent persistent symptoms were fatigue, loss of smell and taste, and arthralgias.

Conclusions

Our results show that it might take months for symptoms to resolve, even among non-hospitalized persons with mild illness course in the acute phase. Continued monitoring for long COVID is needed.

The prevalence of food allergy and other allergic diseases in early childhood in a population-based study: HealthNuts age 4-year follow-up

BACKGROUND

The HealthNuts study previously reported interim prevalence data showing the highest prevalence of challenge-confirmed food allergy in infants internationally. However, population-derived prevalence data on challenge-confirmed food allergy and other allergic diseases in preschool-aged children remain sparse.

OBJECTIVE

This study aimed to report the updated prevalence of food allergy at age 1 year from the whole cohort, and to report the prevalence of food allergy, asthma, eczema, and allergic rhinitis at age 4 years.

METHODS

HealthNuts is a population-based cohort study with baseline recruitment of 5276 one-year-old children who underwent skin prick test (SPT) to 4 food allergens and those with detectable SPT results had formal food challenges. At age 4 years, parents completed a questionnaire (81.3% completed) and those who previously attended the HealthNuts clinic at age 1 year or reported symptoms of a new food allergy were invited for an assessment that included SPT and oral food challenges. Data on asthma, eczema, and allergic rhinitis were captured by validated International Study of Asthma and Allergies in Childhood questionnaires.

RESULTS

The prevalence of challenge-confirmed food allergy at age 1 and 4 years was 11.0% and 3.8%, respectively. At age 4 years, peanut allergy prevalence was 1.9% (95% CI, 1.6% to 2.3%), egg allergy was 1.2% (95% CI, 0.9% to 1.6%), and sesame allergy was 0.4% (95% CI, 0.3% to 0.6%). Late-onset peanut allergy at age 4 years was rare (0.2%). The prevalence of current asthma was 10.8% (95% CI, 9.7% to 12.1%), current eczema was 16.0% (95% CI, 14.7% to 17.4%), and current allergic rhinitis was 8.3% (95% CI, 7.2% to 9.4%). Forty percent to 50% of this population-based cohort experienced symptoms of an allergic disease in the first 4 years of their life.

CONCLUSIONS

Although the prevalence of food allergy decreased between age 1 year and age 4 years in this population-based cohort, the prevalence of any allergic disease among 4-year-old children in Melbourne, Australia, is remarkably high.

Negative symptoms in individuals at clinical high risk of psychosis

Negative symptoms are present in the psychosis prodrome. However, the extent to which these symptoms are present prior to the onset of the first episode of psychosis remains under-researched. The goal of this study is to examine negative symptoms in a sample of individuals at clinical high risk (CHR) for psychosis and to determine if they are predictive of conversion to psychosis. Participants (n=138) were all participants in the North American Prodrome Longitudinal Study (NAPLS 1) project. Negative symptoms were assessed longitudinally using the Scale of Prodromal Symptoms. The mean total negative symptom score at baseline was 11.0, with 82.0% of the sample scoring at moderate severity or above on at least one negative symptom. Over the course of 12 months, the symptoms remained in the above moderate severity range for 54.0% of participants. Associations between individual symptoms were moderate, and a factor analysis confirmed that all negative symptoms loaded heavily on one factor. Negative symptoms were more severe and persistent overtime in those who converted to psychosis, significantly predicting the likelihood of conversion. Thus, early and persistent negative symptoms may represent a vulnerability for risk of developing psychosis.

The long-term genetic stability and individual specificity of the human gut microbiome

By following up the gut microbiome, 51 human phenotypes and plasma levels of 1,183 metabolites in 338 individuals after 4 years, we characterize microbial stability and variation in relation to host physiology. Using these individual-specific and temporally stable microbial profiles, including bacterial SNPs and structural variations, we develop a microbial fingerprinting method that shows up to 85% accuracy in classifying metagenomic samples taken 4 years apart. Application of our fingerprinting method to the independent HMP cohort results in 95% accuracy for samples taken 1 year apart. We further observe temporal changes in the abundance of multiple bacterial species, metabolic pathways, and structural variation, as well as strain replacement. We report 190 longitudinal microbial associations with host phenotypes and 519 associations with plasma metabolites. These associations are enriched for cardiometabolic traits, vitamin B, and uremic toxins. Finally, mediation analysis suggests that the gut microbiome may influence cardiometabolic health through its metabolites.

Mental Health Among College Students During the COVID-19 Pandemic in China: A 2-Wave Longitudinal Survey

BACKGROUND

Growing evidence supports a clear association between COVID-19 pandemic and mental health. However, little is known about the longitudinal course of psychopathology in young adults at different stages of the pandemic.

METHODS

This large-scale, longitudinal, population-based survey was conducted among college students in China. The rates of three mental health problems (acute stress, anxiety, and depressive symptoms), and their change patterns at two phases of the pandemic (early vs under-control) were measured. Predictors of changes in mental health symptoms were examined utilizing multivariate regression.

RESULTS

Among the 164,101 college students who participated in the first wave survey (T1=during onset of outbreak), 68,685 (41.9%) completed a follow-up survey (T2=during remission). In the follow-up survey, the prevalence of probable acute stress (T1: 34.6%; T2: 16.4%) decreased, while the rates of depressive (T1: 21.6%; T2: 26.3%) and anxiety symptoms (T1: 11.4%; T2: 14.7%) increased. Senior students, with suspected or conformed cases in their community and COVID-19 related worries (all AORs > 1.20, ps < 0.001) were found to have a higher risk of developing mental health problems in at least one wave. Less physical exercise, low perceived social support, and a dysfunctional family were found to negatively impact psychological symptoms.

CONCLUSIONS

Acute stress, anxiety, and depressive symptoms have been prevalent among college students during the COVID-19 epidemic, and showed a significant increase after the initial stage of the outbreak. Some college students, especially those with the risk factors noted above, exhibited persistent or delayed symptoms.

The Psychological Impacts of a COVID-19 Outbreak on College Students in China: A Longitudinal Study

An outbreak in Wuhan, China in late 2019 of a highly infectious new coronary pneumonia (COVID-19) led to the imposition of countrywide confinement measures from January to March 2020. This is a longitudinal study on changes in the mental health status of a college population before and after their COVID-19 confinement for the first two weeks, focusing on states of psychological distress, depression, anxiety and affectivity. The influence of possible stressors on their mental health were investigated, including inadequate supplies and fears of infection. Five hundred and fifty-five undergraduate students were recruited from Hebei Agricultural University in Baoding, China. The participants completed two online surveys-on anxiety and depression, and on positive and negative affect. One survey was conducted before the confinement and the other was conducted 15-17 days after the start of the confinement. Increases in negative affect and symptoms of anxiety and depression (p-values < 0.001) were observed after 2 weeks of confinement. Inadequate supplies of hand sanitizers, a higher year of study, and higher scores on anxiety and depression were common predictors of increased negative affect, anxiety, and depression across the confinement period. The results suggest that healthcare policymakers should carefully consider the appropriate confinement duration, and ensure adequate supplies of basic infection-control materials.

Reduced disability and mortality among aging runners: a 21-year longitudinal study

BACKGROUND

Exercise has been shown to improve many health outcomes and well-being of people of all ages. Long-term studies in older adults are needed to confirm disability and survival benefits of exercise.

METHODS

Annual self-administered questionnaires were sent to 538 members of a nationwide running club and 423 healthy controls from northern California who were 50 years and older beginning in 1984. Data included running and exercise frequency, body mass index, and disability assessed by the Health Assessment Questionnaire Disability Index (HAQ-DI; scored from 0 [no difficulty] to 3 [unable to perform]) through 2005. A total of 284 runners and 156 controls completed the 21-year follow-up. Causes of death through 2003 were ascertained using the National Death Index. Multivariate regression techniques compared groups on disability and mortality.

RESULTS

At baseline, runners were younger, leaner, and less likely to smoke compared with controls. The mean (SD) HAQ-DI score was higher for controls than for runners at all time points and increased with age in both groups, but to a lesser degree in runners (0.17 [0.34]) than in controls (0.36 [0.55]) (P < .001). Multivariate analyses showed that runners had a significantly lower risk of an HAQ-DI score of 0.5 (hazard ratio, 0.62; 95% confidence interval, 0.46-0.84). At 19 years, 15% of runners had died compared with 34% of controls. After adjustment for covariates, runners demonstrated a survival benefit (hazard ratio, 0.61; 95% confidence interval, 0.45-0.82). Disability and survival curves continued to diverge between groups after the 21-year follow-up as participants approached their ninth decade of life.

CONCLUSION

Vigorous exercise (running) at middle and older ages is associated with reduced disability in later life and a notable survival advantage.

Percent body fat at age 5 predicts earlier pubertal development among girls at age 9

OBJECTIVE

This study examines the causal direction of the relationship between weight status and pubertal timing in girls using a longitudinal sample of 183 white girls followed from ages 5 to 9.

METHODS

Girls' weight status (body mass index percentile, percent body fat, waist circumference) was assessed when they were 5, 7, and 9 years old, and their pubertal development was assessed when they were 9 years old (breast development, Estradiol, Pubertal Development Scale). Information from all measures of pubertal development at 9 years was combined to identify girls exhibiting earlier (N = 44) and later (N = 136) pubertal development relative to the sample. Girls' weight status at each age (5, 7, and 9 years old) and change in weight status across the ages of 5 to 9 years were used to predict their pubertal timing at 9 years of age.

RESULTS

Girls with higher percent body fat at 5 years, and girls with higher percent body fat, higher BMI percentile, or larger waist circumference at 7 years, were more likely to be classified with earlier pubertal development at 9 years. In addition, girls showing larger increases in percent body fat from 5 to 9 years of age, and larger increases in waist circumference from 7 to 9 years of age, were more likely to exhibit earlier pubertal development at 9 years. Results were still present after controlling for accelerated growth.

CONCLUSIONS

Girls with higher weight status in early childhood were more likely to exhibit earlier pubertal development relative to peers at 9 years, indicating that weight status preceded pubertal timing in girls.

Trajectories of picky eating during childhood: A general population study

OBJECTIVE

This cohort study describes the prevalence of picky eating and examines prognostic factors for picky eating trajectories during childhood.

METHODS

4,018 participants of a population-based cohort with measurements from pregnancy onwards were included. Picky eating was assessed by maternal report when children were 1.5, 3, and 6 years old. The associations of child and family characteristics with trajectories of picky eating were examined using logistic regression. Never picky eaters were used as the reference group.

RESULTS

Prevalence of picky eating was 26.5% at 1.5 years of age, 27.6% at the age of 3 and declined to 13.2% at 6 years. Four main picky eating trajectories were defined: (1) never picky eating at all three assessments (55% of children), (2) remitting (0-4 years, 32%), (3) late-onset (6 years only, 4%), and (4) persistent (all ages, 4%). This implies that almost two thirds of the early picky eaters remitted within 3 years. Male sex, lower birth weight, non-Western maternal ethnicity, and low parental income predicted persistent picky eating. More often late-onset picky eaters were children of parents with low income and non-Western ethnicity.

DISCUSSION

We found that nearly half (46%) of children were picky eaters at some point during early childhood. Remittance was very high. This suggests that picky eating is usually a transient behavior and part of normal development in preschool children. However, a substantial group of persistent picky eaters, often from a socially disadvantaged background, continues to have problems beyond the preschool age.

Patterns of intimate partner violence victimization from adolescence to young adulthood in a nationally representative sample

PURPOSE

To determine the prevalence of patterns of intimate partner violence (IPV) victimization from adolescence to young adulthood, and document associations with selected sociodemographic and experiential factors.

METHODS

We used prospective data from the National Longitudinal Study of Adolescent Health to group 4134 respondents reporting only opposite-sex romantic or sexual relationships in adolescence and young adulthood into four victimization patterns: no IPV victimization, adolescent-limited IPV victimization, young adult onset IPV victimization, and adolescent-young adult persistent IPV victimization.

RESULTS

Forty percent of respondents reported physical or sexual victimization by young adulthood. Eight percent experienced IPV only in adolescence, 25% only in young adulthood, and 7% showed persistent victimization. Female sex, Hispanic and non-Hispanic black race/ethnicity, an atypical family structure (something other than two biologic parents, step-family, single parent), more romantic partners, experiencing childhood abuse, and early sexual debut (before age 16) were each associated with one or more patterns of victimization versus none. Number of romantic partners and early sexual debut were the most consistent predictors of violence, its timing of onset, and whether victimization persisted across developmental periods. These associations did not vary by biological sex.

CONCLUSIONS

Substantial numbers of young adults have experienced physical or sexual IPV victimization. More research is needed to understand the developmental and experiential mechanisms underlying timing of onset of victimization, whether victimization persists across time and relationships, and whether etiology and temporal patterns vary by type of violence. These additional distinctions would inform the timing, content, and targeting of violence prevention efforts.

Mental health context of food insecurity: a representative cohort of families with young children

OBJECTIVE

Children from food-insecure families (ie, families that lack access to sufficient, safe, and nutritious food) are at risk for developmental problems. Food insecurity disproportionately occurs among low-socioeconomic status (SES) and low-income families; however, interventions that supplement families' income or diet have not eradicated food insecurity. This may be because food insecurity is also related to nonfinancial factors such as the presence of maternal mental health problems. To clarify whether addressing mothers' mental health problems may be a promising strategy for reducing the burden of food insecurity, we tested the hypothesis that low-SES families are especially vulnerable to food insecurity when the mother experiences depression, alcohol or drug abuse, psychosis spectrum disorder, or domestic violence.

METHODS

We used data from a nationally representative cohort of 1116 British families (the Environmental Risk Longitudinal Study). Food insecurity, family SES, maternal mental health and exposure to domestic violence, and children's behavioral outcomes were measured by using validated methods.

RESULTS

Overall, 9.7% of study families were food-insecure. Among low-SES families, controlling for income variation, food insecurity co-occurred with maternal depression (odds ratio [OR]: 2.82 [95% confidence interval (CI): 1.62-4.93]), psychosis spectrum disorder (OR: 4.01 [95% CI: 2.03-7.94]), and domestic violence (OR: 2.36 [95% CI: 1.18-4.73]). In addition, food insecurity predicted elevated rates of children's behavior problems.

CONCLUSIONS

Among families with young children, food insecurity is frequent, particularly when the mother experiences mental health problems. This suggests that interventions that improve women's mental health may also contribute to decreasing the burden of food insecurity and its impact on the next generation.

Atrophy progression in semantic dementia with asymmetric temporal involvement: a tensor-based morphometry study

We performed a longitudinal anatomical study to map the progression of gray matter atrophy in anatomically defined predominantly left (LTLV) and right (RTLV) temporal lobe variants of semantic dementia (SD). T1-weighted MRI scans were obtained at presentation and one-year follow-up from 13 LTLV, 6 RTLV, and 25 control subjects. Tensor-based morphometry (TBM) in SPM2 was applied to derive a voxel-wise estimation of regional tissue loss over time from the deformation field required to warp the follow-up scan to the presentation scan in each subject. When compared to controls, both LTLV and RTLV showed significant progression of gray matter atrophy not only within the temporal lobe most affected at presentation, but also in the controlateral temporal regions (p<0.05 FWE corrected). In LTLV, significant progression of volume loss also involved the ventromedial frontal and the left anterior insular regions. These results identified the anatomic substrates of the previously reported clinical evolution of LTLV and RTLV into a unique 'merged' clinical syndrome characterized by semantic and behavioral deficits and bilateral temporal atrophy.

Children's spatial thinking: does talk about the spatial world matter?

In this paper we examine the relations between parent spatial language input, children's own production of spatial language, and children's later spatial abilities. Using a longitudinal study design, we coded the use of spatial language (i.e. words describing the spatial features and properties of objects; e.g. big, tall, circle, curvy, edge) from child age 14 to 46 months in a diverse sample of 52 parent-child dyads interacting in their home settings. These same children were given three non-verbal spatial tasks, items from a Spatial Transformation task (Levine et al., 1999), the Block Design subtest from the WPPSI-III (Wechsler, 2002), and items on the Spatial Analogies subtest from Primary Test of Cognitive Skills (Huttenlocher & Levine, 1990) at 54 months of age. We find that parents vary widely in the amount of spatial language they use with their children during everyday interactions. This variability in spatial language input, in turn, predicts the amount of spatial language children produce, controlling for overall parent language input. Furthermore, children who produce more spatial language are more likely to perform better on spatial problem solving tasks at a later age.

The socioeconomic determinants of HIV incidence: evidence from a longitudinal, population-based study in rural South Africa

BACKGROUND

Knowledge of the effect of socioeconomic status on HIV infection in Africa stems largely from cross-sectional studies. Cross-sectional studies suffer from two important limitations: two-way causality between socioeconomic status and HIV serostatus and simultaneous effects of socioeconomic status on HIV incidence and HIV-positive survival time. Both problems are avoided in longitudinal cohort studies.

METHODS

We used data from a longitudinal HIV surveillance and a linked demographic surveillance in a poor rural community in KwaZulu-Natal, South Africa, to investigate the effect of three measures of socioeconomic status on HIV incidence: educational attainment, household wealth categories (based on a ranking of households on an assets index scale) and per capita household expenditure. Our sample comprised of 3325 individuals who tested HIV-negative at baseline and either HIV-negative or -positive on a second test (on average 1.3 years later).

RESULTS

In multivariable survival analysis, one additional year of education reduced the hazard of acquiring HIV by 7% (P = 0.017) net of sex, age, wealth, household expenditure, rural vs. urban/periurban residence, migration status and partnership status. Holding other factors equal, members of households that fell into the middle 40% of relative wealth had a 72% higher hazard of HIV acquisition than members of the 40% poorest households (P = 0.012). Per capita household expenditure did not significantly affect HIV incidence (P = 0.669).

CONCLUSION

Although poverty reduction is important for obvious reasons, it may not be as effective as anticipated in reducing the spread of HIV in rural South Africa. In contrast, our results suggest that increasing educational attainment in the general population may lower HIV incidence.

Mechanisms by which childhood personality traits influence adult health status: educational attainment and healthy behaviors

OBJECTIVE

The purpose of this study was to test a life span health behavior model in which educational attainment and health behaviors (eating habits, smoking, and physical activity) were hypothesized as mechanisms to account for relations between teacher ratings of childhood personality traits and self-reported health status at midlife.

DESIGN

The model was tested on 1,054 members of the Hawaii Personality and Health cohort, which is a population-based cohort participating in a longitudinal study of personality and health spanning 40 years from childhood to midlife.

OUTCOME

Childhood Agreeableness, Conscientiousness, and Intellect-Imagination influenced adult health status indirectly through educational attainment, healthy eating habits, and smoking. Several direct effects of childhood traits on health behaviors and health status were also observed.

CONCLUSION

The model extends past associations found between personality traits and health behaviors or health status by identifying a life-course pathway based on the health behavior model through which early childhood traits influence adult health status. The additional direct effects of personality traits indicate that health behavior mechanisms may not provide a complete account of relations between personality and health.

Olfaction and the 5-year incidence of cognitive impairment in an epidemiological study of older adults

OBJECTIVES

To determine whether odor identification ability is associated with the 5-year incidence of cognitive impairment in a large population of older adults with normal cognition at baseline and whether olfactory impairment contributes to the prediction of cognitive decline.

DESIGN

Population-based longitudinal study.

SETTING

Beaver Dam, Wisconsin.

PARTICIPANTS

One thousand nine hundred twenty participants in the Epidemiology of Hearing Loss Study (mean age 66.9).

MEASUREMENTS

Olfaction was measured using the San Diego Odor Identification Test (SDOIT). Incident cognitive impairment was defined as a Mini-Mental State Examination (MMSE) score of less than 24 or reported diagnosis of dementia or Alzheimer's disease (AD) at follow-up in participants with a MMSE score of 24 or greater and no diagnosis of dementia or AD at baseline.

RESULTS

There was a significant association between olfactory impairment at baseline and 5-year incidence of cognitive impairment (odds ratio (OR)=6.62, 95% confidence interval (CI)=4.36-10.05). The association remained significant after adjusting for possible confounders (OR=3.72, 95% CI=2.31-5.99). The positive predictive value of the SDOIT was 15.9%, the negative predictive value was 97.2%, the sensitivity was 55.1%, and the specificity was 84.4% for 5-year incidence of cognitive impairment.

CONCLUSION

Olfactory impairment at baseline was strongly associated with 5-year incidence of cognitive impairment as measured using the MMSE. Odor identification testing may be useful in high-risk settings, but not in the general population, to identify patients at risk for cognitive decline.

The high societal costs of childhood conduct problems: evidence from administrative records up to age 38 in a longitudinal birth cohort

BACKGROUND

Children with conduct problems that persist into adulthood are at increased risk for future behavioral, health, and social problems. However, the longer term public service usage among these children has not been fully documented. To aid public health and intervention planning, adult service usage across criminal justice, health care, and social welfare domains is compared among all individuals from a representative cohort who followed different conduct problem trajectories from childhood into adulthood.

METHODS

Participants are from the Dunedin Multidisciplinary Health and Development Study, a prospective, representative cohort of consecutive births (N = 1,037) from April 1972 to March 1973 in Dunedin, New Zealand. Regression analyses were used to compare levels of public service usage up to age 38, gathered via administrative and electronic medical records, between participants who displayed distinct subtypes of childhood conduct problems (low, childhood-limited, adolescent-onset, and life-course persistent).

RESULTS

Children exhibiting life-course persistent conduct problems used significantly more services as adults than those with low levels of childhood conduct problems. Although this group comprised only 9.0% of the population, they accounted for 53.3% of all convictions, 15.7% of emergency department visits, 20.5% of prescription fills, 13.1% of injury claims, and 24.7% of welfare benefit months. Half of this group (50.0%) also accrued high service use across all three domains of criminal justice, health, and social welfare services, as compared to only 11.3% of those with low conduct problems (OR = 7.27, 95% CI = 4.42-12.0).

CONCLUSIONS

Conduct problems in childhood signal high future costs in terms of service utilization across multiple sectors. Future evaluations of interventions aimed at conduct problems should also track potential reductions in health burden and service usage that stretch into midlife.

Music training for the development of speech segmentation

The role of music training in fostering brain plasticity and developing high cognitive skills, notably linguistic abilities, is of great interest from both a scientific and a societal perspective. Here, we report results of a longitudinal study over 2 years using both behavioral and electrophysiological measures and a test-training-retest procedure to examine the influence of music training on speech segmentation in 8-year-old children. Children were pseudo-randomly assigned to either music or painting training and were tested on their ability to extract meaningless words from a continuous flow of nonsense syllables. While no between-group differences were found before training, both behavioral and electrophysiological measures showed improved speech segmentation skills across testing sessions for the music group only. These results show that music training directly causes facilitation in speech segmentation, thereby pointing to the importance of music for speech perception and more generally for children's language development. Finally these results have strong implications for promoting the development of music-based remediation strategies for children with language-based learning impairments.

Increased alcohol consumption, nonmedical prescription drug use, and illicit drug use are associated with energy drink consumption among college students

OBJECTIVES

This longitudinal study examined the prevalence and correlates of energy drink use among college students, and investigated its possible prospective associations with subsequent drug use, including nonmedical prescription drug use.

METHODS

Participants were 1,060 undergraduates from a large, public university who completed three annual interviews, beginning in their first year of college. Use of energy drinks, other caffeinated products, tobacco, alcohol, and other illicit and prescription drugs were assessed, as well as demographic and personality characteristics.

RESULTS

Annual weighted prevalence of energy drink use was 22.6%(wt) and 36.5%(wt) in the second and third year of college, respectively. Compared to energy drink non-users, energy drink users had heavier alcohol consumption patterns, and were more likely to have used other drugs, both concurrently and in the preceding assessment. Regression analyses revealed that Year 2 energy drink use was significantly associated with Year 3 nonmedical use of prescription stimulants and prescription analgesics, but not with other Year 3 drug use, holding constant demographics, prior drug use, and other factors.

CONCLUSIONS

A substantial and rapidly-growing proportion of college students use energy drinks. Energy drink users tend to have greater involvement in alcohol and other drug use and higher levels of sensation-seeking, relative to non-users of energy drinks. Prospectively, energy drink use has a unique relationship with nonmedical use of prescription stimulants and analgesics. More research is needed regarding the health risks associated with energy drink use in young adults, including their possible role in the development of substance use problems.