Elevated HbA1c levels in individuals not diagnosed with type 2 diabetes in Qatar: A pilot study.

Background: The prevalence of type 2 diabetes (T2D) in Qatar and the Middle East is one of the highest in the world. It is estimated that about one quarter of the individuals with T2D are undiagnosed. Elevated HbA1c levels are an indicator of T2D or a pre-diabetic state. In this study we set out to examine which factors, such as anthropometric and socio-demographic risk factors, are associated with elevated HbA1c levels in a population without T2D. Methods: We examined 191 subjects with no record of T2D. Anthropometrics and HbA1c were measured. Socio-demographic (age, gender, ethnicity and educational level) and health information were assessed through questionnaires. Elevated HbA1c levels were defined as >6.0% (>42 mmol/mol). Individual risk factors were examined in relationship to having elevated HbA1c levels using logistic regression. Results: Thirty-eight (20%) study participants had elevated HbA1c levels. Participants from South Asian and Filipino descent were more likely to present with elevated HbA1c levels than Arab participants (adjusted odds ratios (OR): 13.30 (95% confidence interval (CI): 4.24, 41.79), p <0.001 for South Asian and 4.54 (95% CI: 1.04, 19.83), p= 0.04 for Filipinos). A body mass index of above 30 kg/m2 was associated with elevated HbA1c levels (adjusted OR: 2.90 (95% CI: 1.29, 6.51), p= 0.01). Neither gender nor educational level was associated with elevated HbA1c levels. Conclusions: Elevated HbA1c levels in individuals not diagnosed with diabetes were most frequently found in the South Asian and Filipino immigrant population. Special attention should therefore be given to the early identification of T2D in these subjects

Ethnic and gender differences in advanced glycation end products measured by skin auto-fluorescence.

Advanced glycation end products (AGEs) have been shown to be a predictor of cardiovascular risk in Caucasian subjects. In this study we examine whether the existing reference values are useable for non-Caucasian ethnicities. Furthermore, we assessed whether gender and smoking affect AGEs. Methods: AGEs were determined by a non-invasive method of skin auto-fluorescence (AF). AF was measured in 200 Arabs, 99 South Asians, 35 Filipinos and 14 subjects of other/mixed ethnicity in the Qatar Metabolomics Study on Diabetes (QMDiab). Using multivariate linear regression analysis and adjusting for age and type 2 diabetes, we assessed whether ethnicity, gender and smoking were associated with AF. Results: The mean AF was 2.27 arbitrary units (AU) (SD: 0.63). Arabs and Filipinos had a significant higher AF than the South Asian population (0.25 arbitrary units (AU) (95% CI: 0.11*0.39), p = 0.001 and 0.34 (95% CI: 0.13*0.55), p = 0.001 respectively). Also, AF was significantly higher in females (0.41 AU (95% CI: 0.29*0.53), p 0.001). AF associated with smoking (0.21 AU (95% CI: 0.01*0.41), p = 0.04) and increased with the number of pack-years smoked (p = 0.02). Conclusions: This study suggests that the existing reference values should take ethnicity, gender and smoking into account. Larger studies in specific ethnicities are necessary to create ethnic-and gender-specific reference values

1,5-anhydroglucitol in saliva is a noninvasive marker of short-term glycemic control.

Context: In most ethnicities at least a quarter of all cases with diabetes is assumed to be undiagnosed. Screening for diabetes using saliva has been suggested as an effective approach to identify affected individuals. Objective: The objective of the study was to identify a noninvasive metabolic marker of type 2 diabetes in saliva. Design and Setting: In a case-control study of type 2 diabetes, we used a clinical metabolomics discovery study to screen for diabetes-relevant metabolic readouts in saliva, using blood and urine as a reference. With a combination of three metabolomics platforms based on nontargeted mass spectrometry, we examined 2178 metabolites in saliva, blood plasma, and urine samples from 188 subjects with type 2 diabetes and 181 controls of Arab and Asian ethnicities. Results: We found a strong association of type 2 diabetes with 1,5-anhydroglucitol (1,5-AG) in saliva (P = 3.6 x 10(-13)). Levels of 1,5-AG in saliva highly correlated with 1,5-AG levels in blood and inversely correlated with blood glucose and glycosylated hemoglobin levels. These findings were robust across three different non-Caucasian ethnicities (Arabs, South Asians, and Filipinos), irrespective of body mass index, age, and gender. Conclusions: Clinical studies have already established 1,5-AG in blood as a reliable marker of short-term glycemic control. Our study suggests that 1,5-AG in saliva can be used in national screening programs for undiagnosed diabetes, which are of particular interest for Middle Eastern countries with young populations and exceptionally high diabetes rates

Skin autofluorescence is related to tobacco smoke and nicotine exposure.

Clinical epidemiolog