Gestational age at birth and type 1 diabetes in childhood and young adulthood: a nationwide register study in Finland, Norway and Sweden.

AIMS/HYPOTHESIS: Children and adults born preterm have an increased risk of type 1 diabetes. However, there is limited information on risk patterns across the full range of gestational ages, especially after extremely preterm birth (23-27 weeks of gestation). We investigated the risk of type 1 diabetes in childhood and young adulthood across the full range of length of gestation at birth. METHODS: Data were obtained from national registers in Finland, Norway and Sweden. In each country, information on study participants and gestational age was collected from the Medical Birth Registers, information on type 1 diabetes diagnoses was collected from the National Patient Registers, and information on education, emigration and death was collected from the respective national register sources. Individual-level data were linked using unique personal identity codes. The study population included all individuals born alive between 1987 and 2016 to mothers whose country of birth was the respective Nordic country. Individuals were followed until diagnosis of type 1 diabetes, death, emigration or end of follow-up (31 December 2016 in Finland, 31 December 2017 in Norway and Sweden). Gestational age was categorised as extremely preterm (23-27 completed weeks), very preterm (28-31 weeks), moderately preterm (32-33 weeks), late preterm (34-36 weeks), early term (37-38 weeks), full term (39-41 weeks; reference) and post term (42-45 weeks). HRs and 95% CIs from country-specific covariate-adjusted Cox regression models were combined in a meta-analysis using a common-effect inverse-variance model. RESULTS: Among 5,501,276 individuals, 0.2% were born extremely preterm, 0.5% very preterm, 0.7% moderately preterm, 4.2% late preterm, 17.7% early term, 69.9% full term, and 6.7% post term. A type 1 diabetes diagnosis was recorded in 12,326 (0.8%), 6364 (0.5%) and 16,856 (0.7%) individuals at a median age of 8.2, 13.0 and 10.5 years in Finland, Norway and Sweden, respectively. Individuals born late preterm or early term had an increased risk of type 1 diabetes compared with their full-term-born peers (pooled, multiple confounder-adjusted HR 1.12, 95% CI 1.07, 1.18; and 1.15, 95% CI 1.11, 1.18, respectively). However, those born extremely preterm or very preterm had a decreased risk of type 1 diabetes (adjusted HR 0.63, 95% CI 0.45, 0.88; and 0.78, 95% CI 0.67, 0.92, respectively). These associations were similar across all three countries. CONCLUSIONS/INTERPRETATION: Individuals born late preterm and early term have an increased risk of type 1 diabetes while individuals born extremely preterm or very preterm have a decreased risk of type 1 diabetes compared with those born full term.

Preterm birth and asthma and COPD in adulthood: a nationwide register study from two Nordic countries.

BACKGROUND: Preterm birth affects lungs in several ways but few studies have follow-up until adulthood. We investigated the association of the entire spectrum of gestational ages with specialist care episodes for obstructive airway disease (asthma and chronic obstructive pulmonary disease (COPD)) at age 18-50 years. METHODS: We used nationwide registry data on 706 717 people born 1987-1998 in Finland (4.8% preterm) and 1 669 528 born 1967-1999 in Norway (5.0% preterm). Care episodes of asthma and COPD were obtained from specialised healthcare registers, available in Finland for 2005-2016 and in Norway for 2008-2017. We used logistic regression to estimate odds ratios (ORs) for having a care episode with either disease outcome. RESULTS: Odds of any obstructive airway disease in adulthood for those born at <28 or 28-31 completed weeks were 2-3-fold of those born full term (39-41 completed weeks), persisting after adjustments. For individuals born at 32-33, 34-36 or 37-38 weeks, the odds were 1.1- to 1.5-fold. Associations were similar in the Finnish and the Norwegian data and among people aged 18-29 and 30-50 years. For COPD at age 30-50 years, the OR was 7.44 (95% CI 3.49-15.85) for those born at <28 weeks, 3.18 (95% CI 2.23-4.54) for those born at 28-31 weeks and 2.32 (95% CI 1.72-3.12) for those born at 32-33 weeks. Bronchopulmonary dysplasia in infancy increased the odds further for those born at <28 and 28-31 weeks. CONCLUSION: Preterm birth is a risk factor for asthma and COPD in adulthood. The high odds of COPD call for diagnostic vigilance when adults born very preterm present with respiratory symptoms.

ADHD symptoms and diagnosis in adult preterms: systematic review, IPD meta-analysis, and register-linkage study.

BACKGROUND: This study examined differences in ADHD symptoms and diagnosis between preterm and term-born adults (≥18 years), and tested if ADHD is related to gestational age, birth weight, multiple births, or neonatal complications in preterm borns. METHODS: (1) A systematic review compared ADHD symptom self-reports and diagnosis between preterm and term-born adults published in PubMed, Web of Science, and PROQUEST until April 2021; (2) a one-stage Individual Participant Data(IPD) meta-analysis (n = 1385 preterm, n = 1633 term; born 1978-1995) examined differences in self-reported ADHD symptoms[age 18-36 years]; and (3) a population-based register-linkage study of all live births in Finland (01/01/1987-31/12/1998; n = 37538 preterm, n = 691,616 term) examined ADHD diagnosis risk in adulthood (≥18 years) until 31/12/2016. RESULTS: Systematic review results were conflicting. In the IPD meta-analysis, ADHD symptoms levels were similar across groups (mean z-score difference 0.00;95% confidence interval [95% CI] -0.07, 0.07). Whereas in the register-linkage study, adults born preterm had a higher relative risk (RR) for ADHD diagnosis compared to term controls (RR = 1.26, 95% CI 1.12, 1.41, p < 0.001). Among preterms, as gestation length (RR = 0.93, 95% CI 0.89, 0.97, p < 0.001) and SD birth weight z-score (RR = 0.88, 95% CI 0.80, 0.97, p < 0.001) increased, ADHD risk decreased. CONCLUSIONS: While preterm adults may not report higher levels of ADHD symptoms, their risk of ADHD diagnosis in adulthood is higher. IMPACT: Preterm-born adults do not self-report higher levels of ADHD symptoms, yet are more likely to receive an ADHD diagnosis in adulthood compared to term-borns. Previous evidence has consisted of limited sample sizes of adults and used different methods with inconsistent findings. This study assessed adult self-reported symptoms across 8 harmonized cohorts and contrasted the findings with diagnosed ADHD in a population-based register-linkage study. Preterm-born adults may not self-report increased ADHD symptoms. However, they have a higher risk of ADHD diagnosis, warranting preventive strategies and interventions to reduce the presentation of more severe ADHD symptomatology in adulthood.

Associations of leisure-time physical activity and active school transport with mental health outcomes: A population-based study.

Promoting physical activity can improve population health. This study aimed to examine associations of leisure-time moderate-to-vigorous physical activity and active school transport with mental health, that is, symptoms of depression and anxiety, among 15- to 16-year-old adolescents. We also assessed the relationships with less-studied outcomes, such as chronic stress and visits to school psychologist. A nationwide Finnish cohort of eighth and ninth graders from the School Health Promotion study (32 829 participants; mean age 15.4 years; 53% girls) was studied. We used logistic regression to estimate odds ratios (OR), with models adjusted for major sociodemographic, health behavior, and physical activity variables. Key findings suggest that leisure-time moderate-to-vigorous physical activity is associated with better mental health in a dose-response manner. Even the smallest dose, 30 weekly minutes, was linked to 17% lower odds of chronic stress symptoms compared to inactivity (OR 0.83, 95% CI 0.71-0.96). Compared to non-active transportation, more than 30 min of daily active school transport yielded 19% (OR 1.19, 95% CI 1.07-1.31) and 33% (OR 1.33, 95% CI 1.12-1.58) higher odds of depression symptoms and school psychologist visits, respectively. However, no associations were found for low-to-moderate daily active school transport levels (<30 min). This large-scale study further highlights a positive association between leisure-time physical activity and mental health among youth. Future research should explore what factors might explain the potential adverse mental health outcomes of active school transport.

Are active school transport and leisure-time physical activity associated with performance and wellbeing at secondary school? A population-based study.

BACKGROUND: Physically active pupils may be better and more resilient learners. However, it is unclear whether walking or cycling to school yields similar educational and school-related mental health benefits as leisure-time physical activity. We examined the associations of active school transport and leisure-time moderate-to-vigorous physical activity with perceived academic performance, competency in academic skills, school burnout and school enjoyment. METHODS: We included 34 103 Finnish adolescents (mean age 15.4 years; 53% girls) from the 2015 School Health Promotion study cohort. For the analyses, we used logistic regression, adjusting for major sociodemographic, environmental, lifestyle and physical activity covariates. RESULTS: Active school transport was positively associated with educational outcomes and school enjoyment, but not with school burnout. For example, compared with non-active transport, 10-30 min of daily active school transport was linked to 30% [odds ratio (OR) 1.30, 95% confidence interval (CI) 1.21-1.40] and 17% (OR 1.17, 95% CI 1.08-1.27) higher odds of high perceived academic performance and high reading competency, respectively. Leisure-time physical activity was robustly associated with all outcomes. For example, compared with the inactive, the most physically active adolescents had 86% higher odds of high perceived academic performance (OR 1.86, 95% CI 1.66-2.08), 57% higher odds of high competency in mathematics (OR 1.57, 95% CI 1.39-1.77) and 40% lower odds of school burnout (OR 0.60, 95% CI 0.52-0.69). CONCLUSIONS: Compared with active school transport, leisure-time physical activity was more strongly associated with educational and school-related mental health outcomes. Nevertheless, walking or cycling to school might lead to improvements in classroom performance and school enjoyment.

Association of job strain with accelerometer-based sleep duration and timing of sleep among older employees.

Job strain has been associated with poor sleep quality and could lead to changes in duration and timing of sleep as well. This study examined the association of job strain with sleep duration, bedtimes and awakening times among public sector employees close to their retirement age. Differences in these sleep parameters between workdays and free days across job strain groups were examined. Duration and timing of sleep were measured repeatedly with accelerometers among 466 public sector employees in Finland (mean age 63 years, 86% women), who contributed to 759 measurements in total. Job demands (low/high) and control (low/high) measured by self-reports and job exposure matrix were used to identify low strain (low demand, high control), passive (low, low), active (high, high) and high strain (high, low) jobs. No differences in sleep duration were observed on workdays, whereas on free days those in the high strain group had longer sleep duration than those in the low strain and passive job groups. The high strain group also extended their sleep from workdays to free days more, the extension being on average 59 min (95% CI 42 min-75 min) when adjusted for several sociodemographic, work and health factors. This extension of sleep duration resulted mostly from a greater delay of awakening times from workdays to free days. Psychosocial work factors, such as job strain, need to be considered when promoting sufficient sleep duration among older employees, as those with job strain may have a greater need for recovery and sleep.

Changes in the 24-h movement behaviors during the transition to retirement: compositional data analysis.

BACKGROUND: Transition to retirement is shown to affect sleep, sedentary time and physical activity, but no previous studies have examined how retirement changes the distribution of time spent daily in these movement behaviors. The aim of this study was to examine longitudinally how the composition of 24-h movement behaviors changes during the transition to retirement using compositional data analysis (CoDA). METHODS: We included 551 retiring public sector workers (mean age 63.2 years, standard deviation 1.1) from the Finnish Retirement and Aging study. The study participants wore a wrist-worn ActiGraph accelerometer for one week 24 h per day before and after retirement, with one year between the measurements. The daily proportions to time spent sleeping, in sedentary behavior (SED), light physical activity (LPA) and moderate-to-vigorous physical activity (MVPA) were estimated using the GGIR package. Changes in the daily proportions of movement behaviors were examined using Compositional Data Analysis version of linear mixed models. RESULTS: In general, the proportion of time spent in active behaviors decreased relative to time spent in passive behaviors after retirement (p < .001). This change depended on occupation (occupation*time interaction p < .001). After retirement manual workers increased the proportions of both sleep and SED in relation to active behaviors, whereas non-manual workers increased the proportion of sleep in relation to active behaviors and SED. The proportion of MVPA decreased relatively more than the proportion of LPA (p = 0.01), independently of gender and occupation. CONCLUSIONS: Retirement induced a decrease in the proportion of time spent in active behaviors, especially time spent in MVPA. Future studies are needed to find ways to maintain or increase daily physical activity levels at the cost of sedentary behaviors among retirees.

Distance to sports facilities and low frequency of exercise and obesity: a cross-sectional study.

BACKGROUND: Little research has investigated the associations between proximity to physical activity facilities and behavior-related health and the majority have focused on proximity from home address. We add to the literature by examining proximity of these facilities to work and home address and including a wide range of physical activity facilities. We assess the associations for proximity of physical activity facilities from home and work address with self-reported frequency of exercise and obesity. METHODS: Our analytical sample of 7358 participants was from the 2018 wave of the Swedish Longitudinal Occupational Survey of Health. We used logistic binomial regression adjusting for age, sex, education, civil status, individual socioeconomic status, neighborhood socioeconomic status, number of children under 12 years of age, work strain, and chronic disease. RESULTS: Longer distance from home to paid outdoor and paid indoor physical activity facilities was associated with low frequency of exercise (fully adjusted Relative Risk for both 1.01, 95% CI 1.01-1.02). Associations of any or free outdoor facility with low frequency of exercise were not robust. Findings also indicated associations between long distance from workplace to any and paid outdoor facility and low frequency of exercise. Results for obesity were in the similar direction, however, these were not statistically significant. CONCLUSION: Increased distance of paid outdoor and paid indoor physical activity facilities from home and of paid outdoor facilities from work was associated with low frequency of exercise. Longitudinal and larger studies are needed to confirm our findings, particularly regarding obesity.

Commuting distance and behavior-related health: A longitudinal study.

Health benefits of active commuting and short commuting time are well-documented; however, limited evidence exists on the effects of commuting distance. We examined longitudinal associations between commuting distance and behavior-related health. Participants were from four survey waves of the Swedish Longitudinal Occupational Survey of Health (2012, 2014, 2016, and 2018). Analytical sample included 11,023 individuals and 21,769 observations. Random effects method used binomial logistic regression with generalized estimating equations. The outcomes were self-reported physical inactivity, overweight, smoking, problem drinking, and disturbed sleep. Models were adjusted for age, sex, occupational position, civil status, chronic disease, work strain, number of children under 12, and home/workplace neighborhood socioeconomic status. Using continuous measure, long commuting distance was associated with a higher odds of physical inactivity (OR 1.06; 95% CI, 1.04-1.09 per doubling of distance), overweight (OR 1.02; 95% CI, 1.00-1.04), and disturbed sleep (OR 1.03; 95% CI, 1.00-1.05) in fully adjusted models. Using categorized measure, individuals who commuted longer distance had a higher odds of physical inactivity compared to those with the shortest commute (3.1 km - <7.9 km vs. <3.1 km: OR 1.15; 95% CI, 1.04-1.28 and 7.9 km - <20 km vs. <3.1 km: OR 1.18; 95% CI, 1.06-1.32, fully adjusted model). Such dose-response associations were not observed for overweight or disturbed sleep. Our results suggest short commuting distance may be beneficial for behavior-related health.

Changes in prolonged sedentary behaviour across the transition to retirement.

BACKGROUND: Prolonged sedentary behaviour is associated with a higher risk of cardiometabolic diseases. This longitudinal study examined changes in daily total, prolonged (≥30 min) and highly prolonged (≥60 min) sedentary time across the transition to retirement by gender and occupational status. METHODS: We included 689 aging workers (mean (SD) age before retirement 63.2 (1.6) years, 85% women) from the Finnish Retirement and Aging Study (FIREA). Sedentary time was measured annually using a wrist-worn triaxial ActiGraph accelerometer before and after retirement with on average 3.4 (range 2-4) measurement points. RESULTS: Women increased daily total sedentary time by 22 min (95% CI 13 to 31), prolonged sedentary time by 34 min (95% CI 27 to 42) and highly prolonged sedentary time by 15 min (95% CI 11 to 20) in the transition to retirement, and remained at the higher level of sedentary time years after retirement. The highest increase in total and prolonged sedentary time was observed among women retiring from manual occupations. Men had more total and prolonged sedentary time compared with women before and after retirement. Although no changes in men's sedentary time were observed during the retirement transition, there was a gradual increase of 33 min (95% CI 6 to 60) in prolonged sedentary time from pre-retirement years to post-retirement years. CONCLUSION: The transition to retirement was accompanied by an abrupt increase in prolonged sedentary time in women but a more gradual increase in men. The retirement transition may be a suitable time period for interventions aiming to decrease sedentary behaviour.

Commuting time to work and behaviour-related health: a fixed-effect analysis.

OBJECTIVES: Long commuting times are linked to poor health outcomes, but the evidence is mainly cross-sectional. We examined longitudinal within-individual associations between commuting time and behaviour-related health. METHODS: Data were from the Swedish Longitudinal Occupational Survey of Health study. We selected workers who responded to a minimum of two surveys conducted every other year between 2008 and 2018. We included all study waves with self-reported commuting time (ie, the exposure, 1-5, 6-10, 11-15 or ≥15 hours/week), body mass index (based on weight and height), physical (in)activity, smoking, alcohol use and sleep problems (ie, the outcomes) (Nindividuals=20 376, Nobservations=46 169). We used conditional logistic regression for fixed effects analyses that controls for time-varying confounders by design. Analyses were stratified by working hours: normal (30-40 hours/week) or longer than normal (>40 hours/week) and adjusted for time dependent covariates: age, marital status, occupational position, presence of children, chronic disease, depressive symptoms, job strain and shift work. RESULTS: Those working >40 hours/week had higher odds of physical inactivity (OR 1.25, 95% CI 1.03 to 1.51) and sleep problems (OR 1.16, 95% CI 1.00 to 1.35) when they were commuting >5 hours/week than when they were commuting 1-5 hours/week. Among women working normal hours, longer commuting time associated with lower odds of problem drinking. CONCLUSION: Our findings suggest that lengthy commuting time increases the risk of physical inactivity and sleep problems if individuals have longer than normal weekly working hours. Effects of work arrangements that decrease commuting time should be examined in relation to health behaviours.

The effects of supplementing maternal and infant diets with lipid-based nutrient supplements on physical activity and sedentary behaviour at preschool age in Ghana.

Evidence on whether nutritional supplementation affects physical activity (PA) during early childhood is limited. We examined the long-term effects of lipid-based nutrient supplements (LNS) on total PA, moderate-to-vigorous PA (MVPA) and sedentary behaviour (SB) of children at 4-6 years using an accelerometer for 1 week. Their mothers were enrolled in the International Lipid-based Nutrient Supplement-DYAD randomised controlled trial in Ghana, assigned to daily LNS or multiple micronutrients (MMN) during pregnancy through 6 months postpartum or Fe and folic acid (IFA) during pregnancy and placebo for 6 months postpartum. From 6 to 18 months, children in the LNS group received LNS; the other two groups received no supplements. Analysis was done with intention to treat comparing two groups: LNS v. non-LNS (MMN+ IFA). Of the sub-sample of 375 children fitted with accelerometers, 353 provided sufficient data. Median vector magnitude (VM) count was 1374 (interquartile range (IQR) 309), and percentages of time in MVPA and SB were 4·8 (IQR 2) and 31 (IQR 8) %, respectively. The LNS group (n 129) had lower VM (difference in mean -73 (95 % CI -20, -126), P = 0·007) and spent more time in SB (LNS v. non-LNS: 32·3 v. 30·5 %, P = 0·020) than the non-LNS group (n 224) but did not differ in MVPA (4·4 v. 4·7 %, P = 0·198). Contrary to expectations, provision of LNS in early life slightly reduced the total PA and increased the time in SB but did not affect time in MVPA. Given reduced social-emotional difficulties in the LNS group previously reported, including hyperactivity, one possible explanation is less restless movement in the LNS group.

Daily physical activity patterns among aging workers: the Finnish Retirement and Aging Study (FIREA).

OBJECTIVES: Physical activity is associated with the aging workers' ability to work and predicts working beyond retirement age. To better understand physical activity behaviour in this growing population group, we aimed at characterising 24-hour physical activity patterns among aging workers, and to describe the association between occupational category and total, occupational and leisure-time physical activities. METHODS: We included 878 workers (mean age 62.4 years, SD 1.1, 85% women) from the Finnish Retirement and Aging Study, who wore an accelerometer on their non-dominant wrist for 1 week. We plotted mean hourly activity counts per minute (CPM) for working days and days off. We also compared mean daily CPM between genders and occupations between working days and days off, and work and leisure time by using repeated measures analysis of variance. RESULTS: Activity patterns were different between genders, occupations and types of the day. Women (2580, 95% CI 2540 to 2620) had higher daily mean CPM than men (2110, 95% CI 2020 to 2000). Women in manual occupations were more active than women in non-manual occupations during working days. The differences among men were in the same direction but less pronounced than among women. We found no differences in activity levels between occupations during days off and leisure time on working days. CONCLUSIONS: In aging workers, physical activity differs by gender and occupation during working time, but not during leisure time. As low physical activity is associated with increased risk of early exit from employment, physical activity should be promoted at workplaces, especially among men and people in non-manual occupations.

Changes in Smoking During Retirement Transition: A Longitudinal Cohort Study.

Aims: We examined the effect of retirement transition on changes in smoking, identified trajectories of smoking around the retirement transition, and investigated factors predicting the membership in the trajectories. Methods: This longitudinal cohort study included 1,432 current or former smokers who entered into statutory retirement in 2000-2011 and who filled out two to four questionnaires sent at four-year intervals. Effect of retirement on smoking was analysed as a non-randomized pseudo-trial in which we compared the likelihood of quitting and relapsing smoking between two subsequent survey waves among those who retired and did not retire. We used latent class analysis to identify trajectories of smoking status and smoking intensity (low: <10 cigarettes/day or high: ⩾10 cigarettes/day), and multinomial logistic regression models to assess pre-retirement factors associated with smoking trajectories. Results: Retirement transition was associated with 1.7-fold odds of quitting smoking (95% confidence intervals 1.3-2.2) compared with no retirement transition. We identified three smoking status trajectories: 'sustained non-smoking' (61% of the participants), 'sustained smoking' (23%) and 'decreasing smoking' (16%). For 489 baseline smokers, we identified three smoking intensity trajectories: 'sustained high intensity smoking' (32% of the participants), 'sustained low intensity smoking' (32%) and 'decreasing high intensity smoking' (35%). Living outside an inner urban area predicted membership in the 'decreasing smoking' versus 'sustained smoking' trajectory. Conclusions: Smokers are more likely to quit smoking during transition to retirement than before or after it. Characteristics of the smoking environment may affect smoking behaviour around retirement.

Change in physical activity and accumulation of cardiometabolic risk factors.

This study aims to examine the association between change in physical activity over time and accumulation of cardiometabolic risk factors. Four consecutive surveys (Time 1 to 4) were conducted with 4-year intervals in 1997-2013 (the Finnish Public Sector study). Physical activity of 15,634 cardio-metabolically healthy participants (mean age 43.3 (SD 8.7) years, 85% women) was assessed using four-item survey measure and was expressed as weekly metabolic equivalent (MET) hours in Time 1, 2, and 3. At each time point, participants were categorised into low (<14 MET-h/week), moderate (≥14 to <30 MET-h/week), or high (≥30 MET-h/week) activity level and change in physical activity levels between Time 1 and 3 (over 8 years) was determined. The outcome was the number of incident cardiometabolic risk factors (hypertension, dyslipidemia, diabetes, and obesity) at Time 4. Cumulative logistic regression was used for data analysis. Compared to maintenance of low physical activity, increase in physical activity from low baseline activity level was associated with decreased accumulation of cardiometabolic risk factors in a dose-response manner (cumulative odds ratio [cOR] = 0.73, 95% CI 0.59-0.90 for low-to-moderate and cOR = 0.67, 95% CI 0.49-0.89 for low-to-high, P for trend 0.0007). Decrease in physical activity level from high to low was associated with increased accumulation of cardiometabolic risk factors (cOR = 1.60, 95% CI 1.27-2.01) compared to those who remained at high activity level. Thus even a modest long-term increase in physical activity was associated with reduction in cardiometabolic risk whereas decrease in physical activity was related to increased risk.

Predictors and pathways of language and motor development in four prospective cohorts of young children in Ghana, Malawi, and Burkina Faso.

BACKGROUND: Previous reviews have identified 44 risk factors for poor early child development (ECD) in low- and middle-income countries. Further understanding of their relative influence and pathways is needed to inform the design of interventions targeting ECD. METHODS: We conducted path analyses of factors associated with 18-month language and motor development in four prospective cohorts of children who participated in trials conducted as part of the International Lipid-Based Nutrient Supplements (iLiNS) Project in Ghana (n = 1,023), Malawi (n = 675 and 1,385), and Burkina Faso (n = 1,122). In two cohorts, women were enrolled during pregnancy. In two cohorts, infants were enrolled at 6 or 9 months. In multiple linear regression and structural equation models (SEM), we examined 22 out of 44 factors identified in previous reviews, plus 12 additional factors expected to be associated with ECD. RESULTS: Out of 42 indicators of the 34 factors examined, 6 were associated with 18-month language and/or motor development in 3 or 4 cohorts: child linear and ponderal growth, variety of play materials, activities with caregivers, dietary diversity, and child hemoglobin/iron status. Factors that were not associated with child development were indicators of maternal Hb/iron status, maternal illness and inflammation during pregnancy, maternal perceived stress and depression, exclusive breastfeeding during 6 months postpartum, and child diarrhea, fever, malaria, and acute respiratory infections. Associations between socioeconomic status and language development were consistently mediated to a greater extent by caregiving practices than by maternal or child biomedical conditions, while this pattern for motor development was not consistent across cohorts. CONCLUSIONS: Key elements of interventions to ensure quality ECD are likely to be promotion of caregiver activities with children, a variety of play materials, and a diverse diet, and prevention of faltering in linear and ponderal growth and improvement in child hemoglobin/iron status.

Height gain after two-years-of-age is associated with better cognitive capacity, measured with Raven's coloured matrices at 15-years-of-age in Malawi.

Stunting is a measure of chronic undernutrition, and it affects approximately 160 million children worldwide. Cognitive development of stunted children is compromised, but evidence about the association between height gain in late childhood and adolescent cognitive capacity is scarce. We aimed to determine the association between height gains at different ages, including late childhood, and cognitive capacity at 15-years-of-age. We conducted a prospective cohort study in a rural African setting in Southern Malawi. The study cohort was enrolled between June 1995 and August 1996. It originally comprised mothers of 813 fetuses, and the number of children born live was 767. These children were followed up until the age of 15 years. The anthropometrics were measured at one and 24-months-of-age and 15-years-of-age, and cognitive capacity of participants was assessed at 15-years-of-age with Raven's Coloured Matrices score, mathematic test score, median reaction time (RT) (milliseconds) and RT lapses. The associations between growth and the outcome measures were assessed with linear regression. Raven's Coloured Matrices score was predicted by height gain between 24 months and 15-years-of-age (coefficient 0.85, P = 0.03) and (coefficient 0.69, P = 0.06), but not by earlier growth, when possible confounders were included in the model. The association weakened when school education was further added in the model (coefficient = 0.69, P = 0,060). In conclusion, in rural Malawi, better growth in late childhood is likely to lead to better cognitive capacity in adolescence, partly through more school education. In light of these results, growth promotion should not only be limited to early childhood.

Change in Neighborhood Disadvantage and Change in Smoking Behaviors in Adults: A Longitudinal, Within-individual Study.

BACKGROUND: Evidence for an association between neighborhood disadvantage and smoking is mixed and mainly based on cross-sectional studies. To shed light on the causality of this association, we examined whether change in neighborhood socioeconomic disadvantage is associated with within-individual change in smoking behaviors. METHODS: The study population comprised participants of the Finnish Public Sector study who reported a change in their smoking behavior between surveys in 2008/2009 and 2012/2013. We linked participants' residential addresses to a total population database on neighborhood disadvantage with 250 × 250-m resolution. The outcome variables were changes in smoking status (being a smoker vs. not) as well as the intensity (heavy/moderate vs. light smoker). We used longitudinal case-crossover design, a method that accounts for time-invariant confounders by design. We adjusted models for time-varying covariates. RESULTS: Of the 3,443 participants, 1,714 quit, while 967 began to smoke between surveys. Smoking intensity increased among 398 and decreased among 364 participants. The level of neighborhood disadvantage changed for 1,078 participants because they moved residence. Increased disadvantage was associated with increased odds of being a smoker (odds ratio of taking up smoking 1.23 [95% confidence interval: 1.2, 1.5] per 1 SD increase in standardized national disadvantage score). Odds ratio for being a heavy/moderate (vs. light) smoker was 1.14 (95% confidence interval: 0.85, 1.52) when disadvantage increased by 1 SD. CONCLUSIONS: These within-individual results link an increase in neighborhood socioeconomic disadvantage, due to move in residence, with subsequent smoking behaviors.

Changes in physical activity during transition to retirement: a cohort study.

BACKGROUND: Retirement is a major life transition which may affect lifestyle. The aim of this study is to examine within-individual changes in physical activity during the transition from full-time work to retirement. METHODS: The study population consisted of 9,488 Finnish public-sector employees who retired in 2000-2011 and who reported their leisure-time and commuting physical activity before and after retirement. On average, participants provided data at 3.6 (of the four) repeat examinations during 10 years before and 10 years after the retirement. Physical activity was self-reported and was expressed as weekly metabolic equivalent task (MET) hours. Generalized estimating equations were used to examine physical activity trajectories around retirement. RESULTS: Among participants entering to statutory retirement physical activity first increased by 1.81 MET-hours (95% confidence interval [CI] 1.20 to 2.42) during 4-year retirement transition, but then decreased by -1.80 MET hours (95% CI -2.83 to -0.79) during the subsequent post-retirement period. Older retirement age, higher occupational status and fewer chronic diseases were associated with greater increase in physical activity during transition to statutory retirement. CONCLUSIONS: Statutory retirement appears to be associated with a temporary increase in physical activity. Future research should examine ways to maintain the increased activity level after retirement.