Early-life environment and the risk of eczema at 2 years-Meta-analyses of six Finnish birth cohorts.

BACKGROUND: Urban-related nature exposures are suggested to contribute to the rising prevalence of allergic diseases despite little supporting evidence. Our aim was to evaluate the impact of 12 land cover classes and two greenness indices around homes at birth on the development of doctor-diagnosed eczema by the age of 2 years, and the influence of birth season. METHODS: Data from 5085 children were obtained from six Finnish birth cohorts. Exposures were provided by the Coordination of Information on the Environment in three predefined grid sizes. Adjusted logistic regression was run in each cohort, and pooled effects across cohorts were estimated using fixed or random effect meta-analyses. RESULTS: In meta-analyses, neither greenness indices (NDVI or VCDI, 250 m × 250 m grid size) nor residential or industrial/commercial areas were associated with eczema by age of 2 years. Coniferous forest (adjusted odds ratio 1.19; 95% confidence interval 1.01-1.39 for the middle and 1.16; 0.98-1.28 for the highest vs. lowest tertile) and mixed forest (1.21; 1.02-1.42 middle vs. lowest tertile) were associated with elevated eczema risk. Higher coverage with agricultural areas tended to associate with elevated eczema risk (1.20; 0.98-1.48 vs. none). In contrast, transport infrastructure was inversely associated with eczema (0.77; 0.65-0.91 highest vs. lowest tertile). CONCLUSION: Greenness around the home during early childhood does not seem to protect from eczema. In contrast, nearby coniferous and mixed forests may increase eczema risk, as well as being born in spring close to forest or high-green areas.

Residential green environments are associated with human milk oligosaccharide diversity and composition.

Increased exposure to greener environments has been suggested to lead to health benefits in children, but the associated mechanisms in early life, particularly via biological mediators such as altered maternal milk composition, remain largely unexplored. We investigated the associations between properties of the mother's residential green environment, measured as (1) greenness (Normalized Difference Vegetation index, NDVI), (2) Vegetation Cover Diversity (VCDI) and (3) Naturalness Index (NI), and human milk oligosaccharides (HMOs), known for their immune- and microbiota-related health effects on the infant (N = 795 mothers). We show that HMO diversity increases and concentrations of several individual HMOs and HMO groups change with increased VCDI and NI in residential green environments. This suggests that variation in residential green environments may influence the infant via maternal milk through modified HMO composition. The results emphasize the mediating role of breastfeeding between the residential green environments and health in early life.

Neighborhood Disadvantage, Greenness, and Population Density as Predictors of Breastfeeding Practices: A Population Cohort Study from Finland.

BACKGROUND: Many environmental factors are known to hinder breastfeeding, yet the role of the family living environment in this regard is still poorly understood. OBJECTIVES: We used data from a large cohort to identify associations between neighborhood characteristics and breastfeeding behavior. METHODS: Our observational study included 11,038 children (0-2 years) from the Southwest Finland Birth Cohort. Participant information was obtained from the Medical Birth Register and municipal follow-up clinics. Neighborhood socioeconomic disadvantage, greenness, and population density were measured for a period of 5 years prior to childbirth within the residential neighborhood on a 250 × 250-m grid. Any breastfeeding and breastfeeding at 6 months were the primary outcomes. Binary logistic regression models were adjusted for maternal health and socioeconomic factors. RESULTS: Adjusted analyses suggest that mothers living in less populated areas were less likely to display any breastfeeding (OR: 0.46; 95% CI: 0.36, 0.59) and breastfeeding at 6 months (OR: 0.37; 95% CI: 0.34, 0.40). Mothers living in highly disadvantaged neighborhoods were less likely to display any breastfeeding if the neighborhood was less populated (OR: 0.54; 95% CI: 0.30, 0.95) but more likely to breastfeed at 6 months if the neighborhood was highly populated (OR: 3.74; 95% CI: 1.92, 7.29). Low greenness was associated with higher likelihood of any breastfeeding (OR: 3.82; 95% CI: 1.53, 9.55) and breastfeeding at 6 months (OR: 4.41; 95% CI: 3.44, 5). CONCLUSIONS: Our results suggest that neighborhood characteristics are associated with breastfeeding behavior in Finland. Unravelling breastfeeding decisions linked to the living environment could help identify interventions that will allow the appropriate support for all mothers and infants across different environmental challenges.

Residential greenness and risks of depression: Longitudinal associations with different greenness indicators and spatial scales in a Finnish population cohort.

We carried out a longitudinal study on the associations between residential greenness and depression risk in urban areas in Finland. Residential greenness indicators were estimated within various buffer sizes around individuals' home locations (selected n = 14424) using time-series of normalized differential vegetation index (NDVI) and CORINE land cover data (CLC). We estimated individuals' cumulative exposure to residential greenness over a 5-years and 14-years follow-up. We used doctor-diagnosed depression and Beck Depression Inventory for depression assessment. Our multi-logistic model showed an inverse association between residential greenness and depression, implying lowered depression risk for individuals with higher residential greenness. The association was particularly evident when using NDVI-based residential greenness (within a buffer of 100 m radius) and doctor-diagnosis depression data, adjusted with individual-level covariates. The odds ratio was 0.56 (95% CI 0.33 to 0.96) for the 5-years follow-up, and 0.54 (95% CI 0.30 to 0.98) for the 14-years follow-up. The associations between CLC-based total residential green space and depression varied across the different buffer sizes. In general, all the associations depended on the type of depression assessment, quality of greenness indicators, and the spatial scale of analysis. The associations also varied across the socio-demographic groups and neighborhood socioeconomic disadvantage level.

Modifications to residential neighbourhood characteristics and risk of 79 common health conditions: a prospective cohort study.

BACKGROUND: Observational studies have identified a link between unfavourable neighbourhood characteristics and increased risk of morbidity, but it is unclear whether changes in neighbourhoods affect future disease risk. We used a data-driven approach to assess the impact of neighbourhood modification on 79 health outcomes. METHODS: In this prospective cohort study, we used pooled, individual-level data from two Finnish cohort studies: the Health and Social Support study and the Finnish Public Sector study. Neighbourhood characteristics (mean educational level, median income, and employment rate of residents, and neighbourhood green space) and individual lifestyle factors of community-dwelling individuals were assessed at baseline (at different waves starting between 1998 and 2013). We repeated assessment of neighbourhood characteristics and lifestyle factors approximately 5 years from each baseline assessment, after which follow-up began for health conditions diagnosed according to the WHO International Classification of Diseases for 79 common health conditions using linkage to electronic health records. We used Cox proportional hazard regression models to compute adjusted hazard ratios (HRs) of incident disease associated with neighbourhood characteristics and changes in neighbourhood characteristics over time and logistic regression analysis to compute adjusted odds of association between changes in neighbourhood characteristics and individual lifestyle factors. FINDINGS: 114 786 individuals (87 012 [75·8%] women; mean age 44·4 years [SD 11·1]) had complete data and were included in this cohort study. During 1·17 million person-years at risk, we recorded 164 368 new-onset health conditions and 3438 deaths. Favourable changes in neighbourhood characteristics were associated with reduced risk of all-cause mortality and incidence of 19 specific health conditions. Unfavourable changes were correspondingly associated with increased risk of mortality and 27 specific health conditions. Among participants who did not move residence during the observation period, relative to individuals who continually lived in disadvantaged neighbourhoods, those who experienced favourable modifications in neighbourhood characteristics had a lower risk of future diabetes (HR 0·84, 95% CI 0·75-0·93), stroke (0·49, 0·29-0·83), skin disease (0·72, 0·53-0·97), and osteoarthritis (0·87, 0·77-0·99). Living in a neighbourhood with improving characteristics was also associated with improvements in individual-level health-related lifestyle factors. Among participants who lived in advantaged residential environments at baseline, unfavourable changes in neighbourhood characteristics were associated with an increased risk of diabetes, stroke, skin disease, and osteoarthritis compared with individuals who lived in advantaged neighbourhoods throughout the study period. INTERPRETATION: Favourable modifications to residential neighbourhoods showed robust, longitudinal associations with a range of improvements in health outcomes, including improved health behaviours and reduced risk of cardiometabolic, infectious, and orthopaedic conditions. FUNDING: UK Medical Research Council, US National Institute on Aging, NordForsk, and Academy of Finland.

Spatial modeling of sediment transfer and identification of sediment sources during snowmelt in an agricultural watershed in boreal climate.

Sediment transfer patterns during snowmelt were studied in a small Finnish agricultural watershed. Erosion rates were high as a consequence of high runoff volumes over saturated soil that partly lacked vegetation cover. Automatic high-frequency monitoring data of sediment and phosphorus concentrations in stream showed a clock-wise hysteresis loop as a dominant pattern. GIS-based modeling of runoff and soil erosion, using LiDAR DTM data, suggested that runoff and erosion mostly came from cropland that had the highest sediment contribution index. Also sediment fingerprinting with Cesium-137 suggested cropland and stream bank were the most important sources of suspended sediments in streams. Because a major part of annual sediment transfer takes place during snowmelt, it is a critical period for annual losses of pollutants. Management practices that minimize springtime sediment and pollutant losses from cropland would be needed to make a marked impact on annual pollution transfer to stream waters.

Relict high-Andean ecosystems challenge our concepts of naturalness and human impact.

What would current ecosystems be like without the impact of mankind? This question, which is critical for ecosystem management, has long remained unanswered due to a lack of present-day data from truly undisturbed ecosystems. Using mountaineering techniques, we accessed pristine relict ecosystems in the Peruvian Andes to provide this baseline data and compared it with the surrounding accessible and disturbed landscape. We show that natural ecosystems and human impact in the high Andes are radically different from preconceived ideas. Vegetation of these 'lost worlds' was dominated by plant species previously unknown to science that have become extinct in nearby human-affected ecosystems. Furthermore, natural vegetation had greater plant biomass with potentially as much as ten times more forest, but lower plant diversity. Contrary to our expectations, soils showed relatively little degradation when compared within a vegetation type, but differed mainly between forest and grassland ecosystems. At the landscape level, a presumed large-scale forest reduction resulted in a nowadays more acidic soilscape with higher carbon storage, partly ameliorating carbon loss through deforestation. Human impact in the high Andes, thus, had mixed effects on biodiversity, while soils and carbon stocks would have been mainly indirectly affected through a suggested large-scale vegetation change.