Elevated blood lead levels of refugee children in the United States: a systematic review of recent literature (2011-2021)

Lead is an environmental hazard; even small elevations in blood lead level can cause serious negative health effects in children, including irreversible impacts such as learning difficulties, attention disorders, and behavioral issues. Previous research has shown that some groups are at higher risk for lead poisoning including racial/ethnic minorities, those with low economic status, and immigrants, especially refugees. This systematic review explores recent literature studying disparities in lead poisoning in refugee children. Search terms were chosen with the assistance of a medical librarian, and two independent reviewers assessed articles using a PICOS criteria (Population, Intervention, Comparison, Outcome, Study Design) following the Preferred Reporting Items for Systematic review and Meta-Analysis Protocols (PRIMSA-P) guidelines, a set of evidence-based minimum standards for reporting in systematic reviews. 321 article titles were reviewed, 61 abstracts screened, and 17 methods sections reviewed, ultimately including 13 studies. The studies found a high prevalence of elevated blood lead level among refugee populations when compared to reference populations. Both pre-migration and post-migration factors were identified as contributors to the disparity, and associations were identified between elevated blood lead levels and factors such as country of origin, age, and other health variables. Health providers and resettlement workers should be aware of these disparities and related factors. Testing, care, education and consistent follow-up should be provided.

The impact of greenspace or nature-based interventions on cardiovascular health or cancer-related outcomes: A systematic review of experimental studies

SIGNIFICANCE

Globally, cardiovascular disease (CVD) and cancer are leading causes of morbidity and mortality. While having different etiologies, CVD and cancer are linked by multiple shared risk factors, the presence of which exacerbate adverse outcomes for individuals with either disease. For both pathologies, factors such as poverty, lack of physical activity (PA), poor dietary intake, and climate change increase risk of adverse outcomes. Prior research has shown that greenspaces and other nature-based interventions (NBIs) contribute to improved health outcomes and climate change resilience.

OBJECTIVE

To summarize evidence on the impact of greenspaces or NBIs on cardiovascular health and/or cancer-related outcomes and identify knowledge gaps to inform future research.

METHODS

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 and Peer Review of Electronic Search Strategies (PRESS) guidelines, we searched five databases: Web of Science, Scopus, Medline, PsycINFO and GreenFile. Two blinded reviewers used Rayyan AI and a predefined criteria for article inclusion and exclusion. The risk of bias was assessed using a modified version of the Newcastle-Ottawa Scale (NOS). This review is registered with PROSPERO, ID # CRD42021231619.

RESULTS & DISCUSSION

Of 2565 articles retrieved, 31 articles met the inclusion criteria, and overall had a low risk of bias. 26 articles studied cardiovascular related outcomes and 5 studied cancer-related outcomes. Interventions were coded into 4 categories: forest bathing, green exercise, gardening, and nature viewing. Outcomes included blood pressure (BP), cancer-related quality of life (QoL) and (more infrequently) biomarkers of CVD risk. Descriptions of findings are presented as well as visual presentations of trends across the findings using RAW graphs. Overall studies included have a low risk of bias; and alluvial chart trends indicated that NBIs may have beneficial effects on CVD and cancer-related outcomes.

CONCLUSIONS & IMPLICATIONS

(1) Clinical implication: Healthcare providers should consider the promotion of nature-based programs to improve health outcomes. (2) Policy implication: There is a need for investment in equitable greenspaces to improve health outcomes and build climate resilient neighborhoods. (3) Research or academic implication: Research partnerships with community-based organizations for a comprehensive study of benefits associated with NBIs should be encouraged to reduce health disparities and ensure intergenerational health equity. There is a need for investigation of the mechanisms by which NBIs impact CVD and exploration of the role of CVD biological markers of inflammation among cancer survivors.