Cardiometabolic Profile and Outcomes in Migrant Populations: A Review of Comparative Evidence from Migrants in Europe in Relation to Their Country of Origin.

BACKGROUND: The potential effect of migration on increasing cardiometabolic risk factors remains partially understood. We aim to synthesize the evidence comparing the burden of diabetes and adiposity of migrating populations in Europe, with that of their country of origin. METHODS: We conducted a scoping literature review. We searched PubMed for studies investigating the effect of migration on diabetes or adiposity outcomes among migrants in countries from the European Union or the United Kingdom compared to the population in the country of origin. Studies were qualitatively synthesized in evidence tables and the demographic characteristics, study design, risk factors investigated, and outcomes were quantitatively summarized using measures of central tendency. FINDINGS: Of 1175 abstracts retrieved, 28 studies were eligible. Most of the studies included migrating populations residing in Western (50%), Northern (39%), and Southern Europe (11%) originating from countries in Africa (46%), Asia (29%), or European overseas (25%) regions of which 85% were classified as low-middle-income countries. Most of the studies (93%) had a cross-sectional design. The median number of individuals in the country of origin was greater [917; IQR: 231-1378] than in the receiving country [249; 150-883]. Thirty-five percent of the studies investigated migration as an independent risk factor, whereas 28% contextualized migration into lifestyle changes. The majority of the studies (57%) reported both diabetes and adiposity outcomes. Within the limited evidence available, controversial results were found as some studies showed poorer outcomes for the migrating populations, while others showed the opposite. CONCLUSION: Studies assessing the impact of migration by comparing migrating populations and the population of origin on diabetes and adiposity outcomes have gained interest. So far, the available evidence is highly heterogeneous to inform public health strategies in the receiving countries. We recommend further research including a more robust methodology and in-depth characterization of the migrant populations.

The effectiveness of lifestyle interventions on type 2 diabetes and gestational diabetes incidence and cardiometabolic outcomes: A systematic review and meta-analysis of evidence from low- and middle-income countries.

Background: As lifestyle modification offers a unique strategy to prevent diabetes, we evaluated the effectiveness of lifestyle interventions in the prevention of type 2 diabetes and gestational diabetes in low- and middle-income countries (LMICs). Methods: We did a systematic literature review and meta-analysis. We searched MEDLINE, Embase, Web of Science, and Cochrane Library for randomised controlled trials published in English, Spanish, French, and Portuguese between 1 January 2000 and 15 June 2022, evaluating multi-target and multi-component lifestyle interventions in at-risk populations conducted in LMICs. The main outcomes were incidence of type 2 diabetes and gestational diabetes, and indicators of glycaemic control. We assessed the methodological quality of the studies using the Cochrane risk of bias tool. Inverse-variance random-effects meta-analyses estimated the overall effect sizes. Sources of heterogeneity and study bias were evaluated. The study protocol was registered in PROSPERO (CRD42021279174). Findings: From 14 330 abstracts, 48 (0·3%) studies with 50 interventions were eligible of which 56% were conducted in lower-middle-income countries, 44% in upper-middle, and none in low-income. 54% of the studies were assessed as moderate risk of bias and 14% as high risk. A median of 246 (IQR 137-511) individuals participated in the interventions with a median duration of 6 (3-12) months. Lifestyle interventions decreased the incidence risk ratio of type 2 diabetes by 25% (0·75 [95% CI 0·61 to 0·91]), and reduced the levels of HbA1c by 0·15% [-0·25 to -0·05], fasting plasma glucose by 3·44 mg/dL [-4·72 to -2·17], and 2-hr glucose tolerance by 4·18 mg/dL [-7·35 to -1·02]. No publication bias was suggested for these outcomes. High levels of heterogeneity (I²≥ 81%) were found in most meta-analyses. Exploration using meta-regressions could not identify any explanatory variable, except for fasting glucose for which the quality score of the articles seems to be an effect modifier decreasing slightly the heterogeneity (72%) in the low risk of bias pooled estimate. The effect on gestational diabetes could not be evaluated due to the scarcity of available studies. Interpretation: Comprehensive lifestyle interventions are effective strategies to prevent type 2 diabetes among at-risk populations in LMICs. The heterogeneity identified in our results should be considered when using these interventions to address the onset of type 2 diabetes. Funding: None.