Does IQ Influence Association Between Working Memory and ADHD Symptoms in Young Adults?

OBJECTIVE: This study examined the association between WM and ADHD symptoms in young adults and whether IQ-score influenced this association. METHOD: Data from the 1993 Pelotas (Brazil) Birth Cohort Study were analyzed (N = 2,845). Working memory and ADHD symptoms were collected at 22 years. IQ was examined at age 18. Poisson regression with robust variance was used to assess the associations between working memory and ADHD symptoms. We also evaluated whether IQ modified associations between working memory and ADHD symptoms. RESULTS: Working memory was negatively associated with Inattention symptoms of ADHD. The association between working memory and hyperactivity-impulsivity symptoms of ADHD varied by IQ. CONCLUSIONS: This study provides new insights to theories about the relationship between WM and ADHD symptoms as well as the development of interventions aimed at improving the performance of WM in ADHD.

Is Screen Time Throughout Adolescence Related to ADHD? Findings from 1993 Pelotas (Brazil) Birth Cohort Study.

OBJECTIVE: This study investigated the association between screen time in adolescence and Attention Deficit Disorder (ADHD) at 22 years old. METHOD: A sample of 2333 participants aged 11 years old without ADHD from the 1993 Pelotas Birth Cohort Study (Brazil) was followed up until the age of 22. Screen time variables included time spent in television, video game and computer at 11, 15, and 18 years old. ADHD was assessed at 22 years. RESULTS: ADHD symptoms at 22 years was positively associated with television time at 11 years, computer time at 18 years and total screen time at ages 11, 15, and 18 years. Television time at 11 years and total screen time at 18 years were associated with diagnosis of ADHD at 22 years of age. CONCLUSIONS: Our findings may contribute to future investigations of possible explanatory avenues for these associations.

Screen time and working memory in adolescents: A longitudinal study.

Little is known about the effects of excessive screen time on Working Memory (WM) in adolescents. The aim of this study was to investigate the association between measures of screen time in adolescence and Working Memory. Data from the 1993 Pelotas (Brazil) Birth Cohort Study were analyzed (N = 3625). Self-reported screen time was collected at ages 11, 15 and 18. Working Memory performance (Digit Span backward score) was examined at age 22. Multiple linear regression was used to assess the associations between three screen time measures (television, video game and computer time) for each age and WM at age 22. We also evaluated the direct and indirect effect by mediation analysis, using the intelligence quotient (IQ) at 18 years as mediator. In men, television and video game time at 11 years and computer at ages 11 and 15 years had a positive effect on WM. Also, these effects were mediated through IQ. In women there was no significant association between screen time measures at ages 11, 15, and 18 and WM. This study provides new insights about the relationship between television, videogame, and computer time with WM in adolescents, by exploring the paths of these associations and considering the important mediating role of IQ.

Characterisation of pulmonary function trajectories: results from a Brazilian cohort.

BACKGROUND: Pulmonary function (PF) trajectories are determined by different exposures throughout the life course. The aim of this study was to investigate characteristics related to PF trajectories from 15 to 22 years in a Brazilian cohort. METHODS: A birth cohort study (1993 Pelotas Birth Cohort) was conducted with spirometry at 15, 18 and 22 years. PF trajectories were built based on z-score of forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and their ratio using a group-based trajectory model. Associations with exposures reported from perinatal to 22 years were described. RESULTS: Three trajectories, low (LT), average (AT) and high (HT) were identified in 2917 individuals. Wealthiest individuals belonged to the HT of FEV1 (p=0.023). Lower maternal pregestational body mass index (BMI) (22.4±0.2; p<0.001 and 22.1±0.14; p<0.001) and lower birth weight (3164.8±25.4; p=0.029 and 3132.3±19.4; p=0.005) were related to the LT of FEV1 and FVC. Mother's smoking exposure during pregnancy (37.7%; p=0.002), active smoking at ages 18 and 22 years (20.1% and 25.8%; p<0.001) and family history of asthma (44.8%; p<0.001) were related to the LT of FEV1/FVC. Wheezing, asthma and hospitalisations due to respiratory diseases in childhood were related to the LT of both FEV1 and FEV1/FVC. Higher BMIs were related to the HT of FEV1 and FVC at all ages. CONCLUSIONS: PF trajectories were mainly related to income, pregestational BMI, birth weight, hospitalisation due to respiratory diseases in childhood, participant's BMI, report of wheezing, medical diagnosis and family history of asthma, gestational exposure to tobacco and current smoking status in adolescence and young adult age.

Growth from birth to adolescence and bone mineral density in young adults: The 1993 Pelotas birth cohort.

BACKGROUND: The study examined the association of body size (weight and length) at birth and gain in height and weight during childhood and adolescence with areal bone mineral density (aBMD) in adulthood for women and men. METHODS: 756 members (335 men and 421 women) of the 1993 Pelotas (Brazil) Birth cohort were studied. Data on weight and length/height were obtained at birth and subsequent follow-ups at 1, 4, 11, 15, 18, and 22 years of age and specific z scores were calculated by sex. The outcome was whole body aBMD (g/cm²) measured at 22 years of age using dual-energy X-ray absorptiometry (DXA). The effects of exposures, weight and length/height gain, were analyzed using conditional relative weight (CWh) and conditional length/height (CH). Linear regression models were adjusted for multiple confounders, including mother's educational level, family income, maternal smoking during pregnancy, gestational age, breastfeeding and skin color. RESULTS: In the adjusted models, among men greater height gain at 4, 11, and 18 years of age was associated with higher whole body aBMD, and the result with greatest magnitude was at 11 years of age (ß 0.018 g/cm²; 95%CI 0.006; 0.030). Among women, aBMD was associated with height gain at all assessments from 1-15 years, with greatest effect size at 4 years of age (ß 0.017 g/cm²; 95%CI 0.007; 0.027). Regarding to body weight, among men, greater weight at 4 and 15 years were associated with higher aBMD, with the highest coefficients for 15 years of age (ß 0.015 g/cm²; 95%CI 0.003; 0.027); for women, except at birth, all weight gain variables were associated with aBMD and the highest coefficients were observed at 4 years (ß 0.025 g/cm²; 95%CI 0.015; 0.035). CONCLUSIONS: In this birth cohort, height and weight gain, especially from 4 to 15 years have important positive implications for aBMD to early adulthood.

Prevalence and associated factors of supine sleep position in 3-month-old infants: findings from the 2015 Pelotas (Brazil) Birth Cohort.

BACKGROUND: Non-supine infant sleep position is an important modifiable risk factor for sudden unexpected death in infancy. The aim of this study was to assess the prevalence of supine sleep position and associated factors among 3-month-old infants from a birth cohort in the city of Pelotas, southern Brazil. METHODS: The present study evaluated longitudinal data from the 2015 Pelotas Birth Cohort. Study outcome was supine infant sleep position, defined as the appropriate position, among 3-month-old children. Demographic, socioeconomic, behavioral, and health characteristics collected at birth and at the 3-month follow-up were investigated as possible associated factors. The prevalence of each associated factor was investigated, and crude and hierarchical adjusted analyses were performed using Poisson regression. RESULTS: Among the 4108 infants assessed in this study, 2274 (55.4%) slept in supine position at 3 months and only 66 (1.6%) in prone position. Maternal white skin color, higher family income and maternal schooling, advanced maternal age, maternal cohabiting with a partner, receiving counseling from health care professionals and non-bed-sharing were associated with higher prevalence of infants sleeping in supine position at 3 months. All these variables remained associated in our hierarchical adjusted analyses except maternal cohabitation with a partner. Participants with white mothers were more likely to sleep in supine position (PR: 1.23; 95%CI: 0.75-0.89) compared to participants with black mothers. Those belonging to the richest quintile were more likely to sleep in supine position (PR: 1.49; 95%CI: 1.35-1.65) compared to those who belong to the poorest. Mothers aged 31-36 years were more likely to choose supine sleep position (PR: 1.65; 95%CI: 1.42-1.92) compared to mothers younger than 19 years. CONCLUSIONS: The findings of the present study showed the influence of maternal age, socioeconomic status, and counseling on infant sleep habits as predictors of choice of infant sleep position in a Brazilian population. It is recommended to implement informative campaigns and public policies to at-risk population and to improve recommendations from health care professionals.

Longitudinal association of adiposity with wheezing and atopy at 22 years: the 1993 Birth Cohort, Pelotas, Brazil.

PURPOSE: Asthma is a highly prevalent noncommunicable lung disease. The aim of this study was to evaluate the longitudinal association of obesity/adiposity with wheezing and atopy. METHODS: The population of the study was composed of participants from the 1993 Pelotas (Brazil) Birth Cohort. The following outcome variables were measured at 22 years: wheezing in the last 12 months, wheezing with atopy, wheezing without atopy, only atopy, and persistent wheezing at 18 and 22 years. Exposure variables were obesity body mass index, percent fat mass (FM), and fat mass index, which were obtained by precise methods (BOD POD and dual-energy X-ray absorptiometry [DXA]). Crude and adjusted logistic and multinomial logistic regressions were used in the analyses. RESULTS: The prevalence of wheezing (with and without atopy), wheezing without atopy, only atopy, and persistent wheezing were 10.6%, 3.9%, 30.9%, and 4.0%, respectively. To be obese or to belong to the highest tertile of obesity/adiposity at two follow-ups showed a cumulative and positive association with wheezing in the adjusted analysis; for atopy there was no significant association. The odds ratio (OR) for wheezing according to the percentage of total FM measured by DXA in the highest tertile at both follow-ups was 1.58 (95% CI: 1.14-2.20) against an OR of 1.16 (95% CI: 0.92-1.47) for atopy. Persistent wheezing was also associated with adiposity, but without statistical significance. CONCLUSIONS: We found a positive longitudinal association between several measures of adiposity and wheezing at 22 years old. The effect was higher for cumulative adiposity; the results for atopy were not consistent.

Visceral and subcutaneous abdominal adiposity and pulmonary function in 30-year-old adults: a cross-sectional analysis nested in a birth cohort.

BACKGROUND: Several studies have verified body fat distribution in association with pulmonary function (PF), mainly waist circumference, but few have used measures able to distinguish abdominal fat compartments. The present study aims to verify the association of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) with PF measures. METHODS: In 1982, all hospital births occurring in Pelotas, Brazil, were identified and those livebirths have been followed. In 2012-13, the cohort participants were evaluated and VAT and SAT measured using ultrasound; forced expiratory volume in the first second (FEV1) or forced vital capacity (FVC) were patronized in z-scores stratified by sex. The associations were verified using crude and adjusted linear regressions. RESULTS: The present analyses comprised 3438 individuals (1721 women). VAT was inversely associated with spirometric parameters, in both crude and adjusted models. SAT showed inverse associations in the crude analyzes in males and a positive trend after adjustment, except for SAT and FVC in males. To each centimeter of VAT, mean adjusted FEV1 z-scores decreased 0.072 (95% CI -0.107; -0.036) in men and 0.127 (95% CI -0.164; -0.090) in women, and FVC z-scores decreased -0.075 (95% CI -0.111; -0.039) and 0.121 (95% CI -0.158; -0.083), in men and women, respectively. CONCLUSIONS: VAT has a consistent inverse association with FEV1 and FVC in both sexes. On the other hand, SAT showed inconsistent results with PF parameters.

Multimorbidity in adults from a southern Brazilian city: occurrence and patterns.

OBJECTIVES: The aim of this study was to evaluate occurrences and patterns of multimorbidity in adults from a southern Brazilian city. METHODS: A population-based cross-sectional study was carried out in 2012 through face-to-face interviews with adults (20 or more years) living in Pelotas, southern Brazil. Multimorbidity was evaluated by a list of 11 morbidities (based on medical diagnosis; Patient Health Questionnaire 9 for depression; and Anatomical Therapeutic Chemical index) and operationalized according to two cutoff points: ≥2 and ≥3 morbidities. Descriptive analysis and factor analysis (FA) were performed. RESULTS: The sample was made up of 2927 adults. Multimorbidity reached 29.1 % (95 % CI: 27.1; 31.1) for ≥2, and 14.3 % (95 % CI: 12.8; 15.8) for ≥3 morbidities and was greater in females, older people, those with less schooling and those from lower economic classes. Four pairs (frequency ≥5 %) and four triplets (frequency ≥2 %) were observed. Two patterns of morbidities (cardiometabolic and joint problems; and respiratory diseases) explained 93 % of total variance. CONCLUSIONS: Multimorbidity was common in the studied population. The observed patterns may be used to generate and improve Brazilian diseases guidelines.