Sandra Pinho Silveiro

Diabetes Melito: Diagnóstico, Classificação e Avaliação do Controle Glicêmico

Diabetes mellitus and other categories of impaired glucose tolerance are frequent in the adult population and are associated with an increased risk for cardiovascular disease and microvascular complications. The diagnosis of these entities should be performed early and using sensitive and accurate methods, since lifestyle changes and correction of hyperglycemia may delay the incidence of diabetes and its complications. Glucose tolerance test is the reference method and the diagnosis of diabetes and impaired glucose tolerance are established when the 2h plasma glucose after an oral intake of 75g of glucose is ³200mg/dl or ³140 and <200mg/dl, respectively. When it is not possible to perform this test, fasting plasma glucose levels ³126mg/dl or ³110 and <126mg/dl, respectively, are used to establish the diagnosis of diabetes and impaired fasting plasma glucose. Glycohemoglobin should not be used for the diagnosis but it is the reference method for evaluation of the long-term glucose control. The etiological classification of diabetes mellitus includes 4 categories: type 1 diabetes, type 2 diabetes, other specific types of diabetes and gestational diabetes. The assignment of the patient in each category usually is made on clinical grounds, however in some case the measurement of C-peptide and autoantibodies are necessary.

Five-Year Prospective Study of Glomerular Filtration Rate and Albumin Excretion Rate in Normofiltering and Hyperfiltering Normoalbuminuric NIDDM Patients

OBJECTIVE To evaluate the evolution of glomerular filtration rate (GFR) and albumin excretion rate (AER) of normofiltering (NF) and hyperfiltering (HF) normoalbuminuric NIDDM patients. RESEARCH DESIGN AND METHODS A longitudinal study of 32 normoalbuminuric (AER < 20 μg/min) NIDDM patients and 20 age-, sex-, and BMI-matched normal individuals was done. Subjects had their GFR (51Cr-labeled EDTA single-injection method) measured at entry and after 40 and 60 months. At entry, 13 NIDDM patients had GFR values above the upper limit of the normal range in our laboratory (> 137 ml · min−1 x 1.73 m−2) and were considered as HF. In NIDDM patients, the 24-h AER (radioimmunoassay), HbA1c, urinary urea, and mean arterial blood pressure (MBP) were analyzed at entry and after 40 and 60 months. RESULTS There was a significant decline of GFR in NIDDM patients and normal subjects at 60 months. The decline was significantly greater in HF patients (−0.61 ml · min−1.month−1; P = 0.001) than in NF (−0, 18) and control subjects (−0, 14); the rate of change in NF and control subjects was the same (P > 0.05). In stepwise multiple regression analysis, with GFR decline as the dependent variable and GFR and AER at baseline, age and change in MBP, change in urinary urea, change in HbA1c, and change in therapy as independent variables, only baseline GFR (R2 = 0.19, P = 0.002) and age (R2 = 0.31, P = 0.048) were significantly related to the outcome. At 60 months, AER raised > 20 μg/min in three HF and in four NF patients. In logistic regression analysis, only higher initial AER (although still in the normal range; P = 0.037) and an increase in urinary urea (P = 0.021) were significantly related to the later development of microalbuminuria. CONCLUSIONS The GFR of normoalbuminuric NIDDM patients declines significantly over 60 months. This decline is associated to baseline GFR and age. HF NIDDM patients show a faster decline in GFR than NF patients, whose GFR falls at a rate that is compatible with the age-related change observed in normal control subjects. The development of microalbuminuria is related to higher baseline AER and to increases in urinary urea and is similar in NF (4 of 19) and HF (3 of 13) NIDDM patients (P > 0.05).

Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) Equation Pronouncedly Underestimates Glomerular Filtration Rate in Type 2 Diabetes

OBJECTIVE To evaluate the performance of the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation to estimate glomerular filtration rate (GFR) in type 2 diabetic patients with GFR >60 mL/min/1.73 m2. RESEARCH DESIGN AND METHODS This was a cross-sectional study including 105 type 2 diabetic patients. GFR was measured by 51Cr-EDTA method and estimated by the MDRD and CKD-EPI equations. Serum creatinine was measured by the traceable Jaffe method. Bland-Altman plots were used. Bias, accuracy (P30), and precision were evaluated. RESULTS The mean age of patients was 57 ± 8 years; 53 (50%) were men and 90 (86%) were white. Forty-six (44%) patients had microalbuminuria, and 14 (13%) had macroalbuminuria. 51Cr-EDTA GFR was 103 ± 23, CKD-EPI GFR was 83 ± 15, and MDRD-GFR was 78 ± 17 mL/min/1.73 m2 (P < 0.001). Accuracy (95% CI) was 67% (58–74) for CKD-EPI and 64% (56–75) for MDRD. Precision was 21 and 22, respectively. CONCLUSIONS The CKD-EPI and MDRD equations pronouncedly underestimated GFR in type 2 diabetic patients.

The Chronic Kidney Disease Epidemiology Collaboration (CKD‐EPI) equation is less accurate in patients with Type 2 diabetes when compared with healthy individuals

Diabet. Med. 28, 90–95 (2011)

Glomerular filtration rate measurement and prediction equations.

Abstract Chronic kidney disease (CKD) is defined as the presence of kidney damage or a glomerular filtration rate (GFR) <60 mL/min/1.73 m2 for three or more months. Measurement of serum creatinine is the most commonly used method to evaluated kidney function, but it must be included in formulas to estimate GFR, adjusting for age, gender and ethnicity, such as the Modification of Diet in Renal Disease (MDRD) study equation. The performance of this equation is acceptable for patients with CKD but appears to under-estimate GFR in populations with unknown kidney status. A new formula has been developed recently. The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation appears to perform better than the MDRD equation. Cystatin C has been widely evaluated as a marker for GFR and seems to be more sensitive than creatinine. The aim of this review is to discuss the recommendations for detecting CKD, emphasizing the characteristics and limitations of GFR estimating equations and pitfalls in the evaluation of urinary albumin excretion. Clin Chem Lab Med 2009;47:1023–32.

Glomerular hyperfiltration in NIDDM patients without overt proteinuria

Objective— To evaluate the frequency and correlates of glomerular hyperfiltration in NIDDM patients without overt proteinuria. Research Design and Methods— A cross-sectional study was conducted. Seventy-one consecutive NIDDM patients attending an outpatient clinic, with Albustix-tested negative urine and a 24-h AER <200 μgrams/min, were examined for long-term complications of diabetes. We measured their GFR (51Cr-EDTA single-injection method), 24-h AER (RIA), plasma creatinine, HbA1c, total cholesterol, triglycerides, urinary glucose, and urea. Results— GFR above the upper limit of the normal range for age-matched control subjects (137.1 ml·min−1 · 1.73 m2) was present in 15 of 71 (21%) NIDDM patients. Subjects with normal and hyperfiltration did not differ in terms of age, sex distribution, BMI, duration of NIDDM, BP, AER, or frequency of long-term complications. Plasma glucose was significantly higher in subjects with hyperfiltration (mean [range]: 12.8 [4.3–18.7] vs. 8.7 [2.6–17.5] mM). HbA1c failed to reach statistical significance, although it tended to be higher in the group with hyperfiltration (10.4 [6.7–13.9] vs. 9.4 [4.2–16.5]%, P = 0.10). Age (rS −0.37, P = 0.002), FPG (rS 0.45, P < 0.0005), total cholesterol (rS −0.31, P = 0.008), and glycosuria (rS 0.40, P = 0.001) correlated significantly with GFR. In a stepwise multiple regression analysis, FPG, age, and total cholesterol emerged as significant correlates of the dependent variable GFR. Conclusions— Hyperfiltration occurred in 21% of NIDDM patients without overt proteinuria. FPG and age significant correlates of the GFR in these patients. Cholesterol is significantly (although only modestly) correlated with the GFR.

Medida da cintura e razão cintura/quadril e identificação de situações de risco cardiovascular: estudo multicêntrico em pacientes com diabetes melito tipo 2

Abdominal obesity is associated with cardiovascular disease. This study aims to compare two measures of abdominal obesity [waist and wais-to-hip ratio (WHR)] in patients with DM2 to identify cardiovascular risk factors: ischemic cardiopathy, hypertension, dislipidemia, obesity and diabetic nephropathy. A multicentric study was performed in 820 patients with type 2 DM. Waist circumference strongly correlated with body mass index (BMI), for men (r= 0.814; P< 0.05) and women (r= 0.770; P< 0.05). On the other hand, WRH was weakly correlated (r= 0.263, P< 0.05 for men; r= 0.092, P< 0.05 for women). Only waist circumference correlated with systolic pressure (r= 0.211, P< 0.05 for men; r= 0,224, P< 0.05 for women). ROC curve analysis demonstrated the superiority of waist circumference measurement compared to WHR regarding obesity and hypertension for men and women, and dyslipidemia for men. In conclusion, waist circumference is better correlated with cardiovascular risk factor than WRH.

Maternal–Fetal Impact of Vitamin D Deficiency: A Critical Review

Abstract Research into the extra-skeletal functions of vitamin D has been expanding in recent years. During pregnancy, maternal vitamin D status may be of concern because of the key role of this vitamin in fetal skeletal development and due to the association between hypovitaminosis D and adverse maternal–fetal outcomes. Therefore, the objective of this manuscript was to review the maternal–fetal impact of gestational vitamin D deficiency and the benefits of vitamin D supplementation during pregnancy. A literature search was performed in PubMed and Embase employing the following keywords: vitamin D deficiency, pregnancy, 25-hydroxyvitamin D, and hypovitaminosis D. All relevant articles in English language published since 1980 were analysed by the two authors. Neonatal complications derived from vitamin D deficiency include low birth weight, growth restriction, and respiratory tract infection. In the mother, vitamin D deficiency has been associated with altered glucose homeostasis and increased incidence of gestational diabetes mellitus, pre-eclampsia, and bacterial vaginosis. However, the current state of the evidence is controversial for some other endpoints and the actual benefit of vitamin D supplementation in pregnancy remains unclear. Additional longitudinal studies may clarify the actual impact of vitamin D deficiency during pregnancy, and randomised trials are required to define the benefits of vitamin D supplementation in reducing the incidence of adverse outcomes in the mother and infant.

High‐normal levels of albuminuria predict the development of micro‐ and macroalbuminuria and increased mortality in Brazilian Type 2 diabetic patients: an 8‐year follow‐up study

Aim  To analyse the risk factors for the development of micro‐ and macroalbuminuria and mortality rates in a cohort of normoalbuminuric Type 2 diabetes mellitus (DM) patients.

Urinary Albumin Excretion Rate and Glomerular Filtration Rate in Single-Kidney Type 2 Diabetic Patients

OBJECTIVE To evaluate the urinary albumin excretion rate (UAER) and the glomerular filtration rate (GFR) of single-kidney type 2 diabetic patients (SKD) and of single-kidney non-diabetic patients (SKN). RESEARCH DESIGN AND METHODS Patients who had only one kidney for at least 5 years, with no renal disease or hypertension at the time of the nephrectomy and with no calculus or systemic disease at the time of the evaluation, were included in this controlled cross-sectional study A total of 20 SKD (8 men, age 62 ± 9 years; diabetes duration 8.5 ± 7 years), 17 SKN (2 men, age 57 ± 13 years), and 184 type 2 diabetic patients who were matched to the single-kidney diabetic group for age, sex, and BMI were studied. UAER was measured by immunoturbidimetry in timed 24-h sterile urine, and GFR was determined by the 51Cr-EDTA single-injection method. RESULTS SKD patients presented a higher proportion (8 of 20, 40%) of microalbuminuria (UAER 20-200 μg/min) than SKN patients (3 of 17, 17.6%) and type 2 diabetic patients (37 of 184, 20%). SKD patients presented a higher proportion of macroalbuminuria (UAER >200 μg/min; 6 of 20, 30%) than SKN patients (1 of 17, 6%) but were similar to type 2 diabetic patients (43 of 184, 23%). The GFRs of normoalbuminuric SKN (71.7 ± 21.4 ml · min−1 · 1.73 m−2) and SKD patients (73.0 ± 21.5 ml · min−1 · 1.73 m−2) were similar but higher than the one-kidney GFR (GFR ÷ 2) of the age-, sex-, and BMI-matched normal individuals (50.5 ± 9.0 ml · min−1 · 1.73 m−2) and normoalbuminuric type 2 diabetic patients (54.0 ± 11.6 ml · min−1 · 1.73 m−2). CONCLUSIONS Increased GFR related to single-kidney status confers an increased risk of developing renal disease in the presence of diabetes.