High Incidence of Chronic Kidney Disease among Iranian Diabetic Adults: Using CKD-EPI and MDRD Equations for Estimated Glomerular Filtration Rate

Background@#To investigate the population based incidence rate of chronic kidney disease (CKD) and its potential risk factors among Iranian diabetic adults during over 14 years of follow-up. @*Methods@#Two different equations (Chronic Kidney Disease Epidemiology Collaboration [CKD-EPI] and Modification of Diet in Renal Disease [MDRD]) were applied for the calculating the estimated glomerular filtration rate (eGFR). Among a total of 1,374 diabetic Tehranian adults, 797 and 680 individuals were eligible for CKD-EPI and MDRD analyses, respectively. CKD was defined as eGFR lower than 60 mL/min/1.73 m2. Multivariable Cox proportional hazard models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CI) for all potential risk factors. @*Results@#The incidence rates (95% CI) of CKD per 1,000 person-years were 43.84 (39.49 to 48.66) and 55.80 (50.29 to 61.91) based on CKD-EPI and MDRD equations, respectively. Being older, a history of cardiovascular disease, and having lower levels of eGFR were significant risk factors in both equations. Moreover, in CKD-EPI, using glucose-lowering medications and hypertension, and in MDRD, female sex and fasting plasma glucose ≥10 mmol/L were also independent risk factors. Regarding the discrimination index, CKD-EPI equation showed a higher range of C-index for the predicted probability of incident CKD in the full-adjusted model, compared to MDRD equation (0.75 [0.72 to 0.77] vs. 0.69 [0.66 to 0.72]). @*Conclusion@#We found an incidence rate of more than 4%/year for CKD development among our Iranian diabetic population. Compared to MDRD, it can be suggested that CKD-EPI equation can be a better choice to use for prediction models of incident CKD among the Iranian diabetic populations.

High Incidence of Chronic Kidney Disease among Iranian Diabetic Adults: Using CKD-EPI and MDRD Equations for Estimated Glomerular Filtration Rate

Background@#To investigate the population based incidence rate of chronic kidney disease (CKD) and its potential risk factors among Iranian diabetic adults during over 14 years of follow-up. @*Methods@#Two different equations (Chronic Kidney Disease Epidemiology Collaboration [CKD-EPI] and Modification of Diet in Renal Disease [MDRD]) were applied for the calculating the estimated glomerular filtration rate (eGFR). Among a total of 1,374 diabetic Tehranian adults, 797 and 680 individuals were eligible for CKD-EPI and MDRD analyses, respectively. CKD was defined as eGFR lower than 60 mL/min/1.73 m2. Multivariable Cox proportional hazard models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CI) for all potential risk factors. @*Results@#The incidence rates (95% CI) of CKD per 1,000 person-years were 43.84 (39.49 to 48.66) and 55.80 (50.29 to 61.91) based on CKD-EPI and MDRD equations, respectively. Being older, a history of cardiovascular disease, and having lower levels of eGFR were significant risk factors in both equations. Moreover, in CKD-EPI, using glucose-lowering medications and hypertension, and in MDRD, female sex and fasting plasma glucose ≥10 mmol/L were also independent risk factors. Regarding the discrimination index, CKD-EPI equation showed a higher range of C-index for the predicted probability of incident CKD in the full-adjusted model, compared to MDRD equation (0.75 [0.72 to 0.77] vs. 0.69 [0.66 to 0.72]). @*Conclusion@#We found an incidence rate of more than 4%/year for CKD development among our Iranian diabetic population. Compared to MDRD, it can be suggested that CKD-EPI equation can be a better choice to use for prediction models of incident CKD among the Iranian diabetic populations.

Establishment of the trimester-specific reference range for free thyroxine index.

BACKGROUND: Accurate assessment of thyroid status during pregnancy is vital for maternal and fetal health. Because free thyroxine (FT4) values in pregnancy vary widely between methods, assessment of total T4 (TT4) and FT4 index (FT4I) may be superior to FT4 in pregnant women. However, trimester-specific reference intervals for FT4I have not yet been established. In this longitudinal self-sequential survey, we aimed at determining the trimester-specific reference range for FT4I in healthy Iranian women with singleton pregnancies. METHODS: A total of 466 healthy pregnant women were evaluated. After exclusion of women with history, ultrasonographic, or laboratory evidence of any thyroid disorder or iodine deficiency and those who were positive for thyroid autoantibodies, 152 women entered the study. Serum thyrotropin (TSH), TT4, and triiodothyronine-resine uptake were measured by an immunoassay method. Reference intervals were defined as 5th and 95th percentiles, using the bootstrap-based procedure. RESULTS: Mean values in the first, second, and third trimesters were 1.7±1.5, 1.9±1.8, and 1.9±1.8 mIU/L for TSH; 12.9±3, 14.4±3.1, and 13.6±3.3 µg/dL for TT4; and 12.8±3.5, 14.2±3.3, and 13.5±3.8 for FT4I, respectively. Reference intervals in the first, second, and third trimesters were as follows (respectively): TSH-0.2-3.9, 0.5-4.1, and 0.6-4.1 mIU/L; TT4-8.2-18.5, 10.1-20.6, and 9-19.4 µg/dL; and FT4I-8.5-19, 9.7-21, and 8.7-20.4. Serum TSH had no significant correlation with TT4. Serum TSH had a significant but weak correlation with FT4I only in the first trimester (r=-0.24, p=0.006). CONCLUSION: This study, for the first time, establishes the trimester-specific reference intervals for FT4I in a reference population of normal iodine-sufficient pregnant Iranian women.

Prevalence of metabolic syndrome by the Adult Treatment Panel III, International Diabetes Federation, and World Health Organization definitions and their association with coronary heart disease in an elderly Iranian population

<p><b>INTRODUCTION</b>To determine the prevalence of the metabolic syndrome (MS) in an Iranian elderly population and show its association with coronary heart disease (CHD).</p><p><b>MATERIALS AND METHODS</b>This is a cross-sectional study on 720 Iranian men and women aged > or = 65 years who participated in the Tehran Lipid and Glucose Study (TLGS). Logistic regression analysis was used to estimate the odds ratio (OR) of developing CHD in model 1, an age-adjusted model; model 2, adjusted for age, smoking status, premature history of CHD and low-density lipoprotein (LDL) cholesterol; and model 3, adjusted for mentioned variables plus the MS components.</p><p><b>RESULTS</b>The prevalence of MS was 50.8%, 41.8% and 41.9% based on the Adult Treatment Panel (ATPIII), the World Health Organisation (WHO), and the International Diabetes Federation (IDF) definitions, respectively. The IDF definition showed high agreement with the ATPIII definition. Age-adjusted OR (95% CI) of the MS for CHD was 1.6 (1.2 to 2.2) by both the ATPIII and WHO definitions and 1.4 (1.0 to 1.9) by the IDF definition. IDF-defined MS lost its association with CHD in model 2. In model 3, obesity (WHO definition) and high blood pressure (ATPIII and WHO definitions) were associated with CHD.</p><p><b>CONCLUSIONS</b>In an elderly Iranian population MS is highly prevalent. ATPIII and WHO definitions seem to be more pertinent than IDF for screening CHD risk. None of these definitions showed association with CHD when considering their components.</p>