Adult-onset diabetes in Middle Eastern immigrants to Sweden: Novel subgroups and diabetic complications-The All New Diabetes in Scania cohort diabetic complications and ethnicity.

BACKGROUND: Middle Eastern immigrants to Europe represent a high risk population for type 2 diabetes. We compared prevalence of novel subgroups and assessed risk of diabetic macro- and microvascular complications between diabetes patients of Middle Eastern and European origin. METHODS: This study included newly diagnosed diabetes patients born in Sweden (N = 10641) or Iraq (N = 286), previously included in the All New Diabetes in Scania cohort. The study was conducted between January 2008 and August 2016. Patients were followed to April 2017. Incidence rates in diabetic macro- and microvascular complications were assessed using cox-regression adjusting for the confounding effect of age at onset, sex, anthropometrics, glomerular filtration rate (eGFR) and HbA1c. FINDINGS: In Iraqi immigrants versus native Swedes, severe insulin-deficient diabetes was almost twice as common (27.9 vs. 16.2% p < 0.001) but severe insulin-resistant diabetes was less prevalent. Patients born in Iraq had higher risk of coronary events (hazard ratio [HR] 1.84, 95% CI 1.06-3.12) but considerably lower risk of chronic kidney disease (CKD) than Swedes (HR 0.19; 0.05-0.76). The lower risk in Iraqi immigrants was partially attributed to better eGFR. Genetic risk scores (GRS) showed more genetic variants associated with poor insulin secretion but lower risk of insulin resistance in the Iraqi than native Swedish group. INTERPRETATION: People with diabetes, born in the Middle East present with a more insulin-deficient phenotype and genotype than native Swedes. They have a higher risk of coronary events but lower risk of CKD. Ethnic differences should be considered in the preventive work towards diabetes and its complications.

Pro-Enkephalin and its association with renal function in Middle Eastern immigrants and native Swedes.

Iraqi-born immigrants residing in Sweden exhibit lower blood pressure as well as better renal function despite an overall worse metabolic risk profile in comparison with native Swedes. This may indicate the presence of cardiorenal protective mechanisms in the Middle Eastern population. Hence, the aim of this study was to investigate whether the association between renal function and Pro-Enkephalin (PENK), a biomarker predictive of both acute and chronic kidney dysfunction, differs across ethnicities. The MEDIM population-based study including a cohort of women and men, born in Iraq or Sweden, aged 30-75 years was conducted in Malmö, Sweden, from 2010 to 2012. The study included fasting blood samples, physical examinations and self-administrated questionnaires. Despite significantly better renal function assessed by creatinine-based eGFR in the Iraqi group, levels of PENK did not differ between the groups, (70.0 pmol/L, born in Iraq (n = 1263) vs 71.1, born in Sweden (n = 689), p = .4). However, the association between PENK and renal function was relatively weaker in the Iraqi born group, as supported by a significant interaction between PENK and country of birth (PInteraction= Country of birth x PENK = 0,010). This observational study suggests that the association between renal function and PENK was weaker in Middle Eastern immigrants. This is of interest as PENK may exhibit a direct effect on renal function, however further research is needed including studies on causality.

Renal function and its association with blood pressure in Middle Eastern immigrants and native Swedes.

BACKGROUND: Iraqi-born immigrants residing in Sweden are at high risk for type 2 diabetes, obesity and hyperlipidemia compared with native Swedes. Paradoxically, hypertension is less prevalent in this immigrant population. The aim of this study was to investigate differences in renal function and further if differences in blood pressure (BP) levels were associated with differences across ethnicities in renal function as a possible explanation to the paradox. METHODS: A population-based, cross-sectional study of men and women, born in Iraq or Sweden, aged 30-75 years was conducted in Malmö, Sweden, from 2010 to 2012. Blood samples were drawn, physical examinations performed and self-administrated questionnaires were assessed. Estimated glomerular filtration rate (eGFR) was calculated from the Caucasian Asian Pediatric Adult cohort formula based on cystatin C. RESULTS: Participants without history of cardiovascular disease born in Iraq (n = 1214), irrespective of age and sex, presented with higher eGFR than participants born in Sweden (n = 659), (96.5 ml/min per 1.73 m vs. 93.6, P = 0.009). Furthermore, eGFR showed weaker association with BP in Iraqis than in Swedes, especially for SBP. The relationship was confirmed by a significant interaction between eGFR and country of birth (Pinteraction country of birth × eGFRcystatinC = 0.004). CONCLUSION: The current study shows differences across ethnicities in renal function and its associations with BP. More studies are needed to understand mechanisms contributing to BP regulation and renal function in populations of different ethnic backgrounds.