Weight, body mass index (BMI) and energy expenditure/energy intake (EE/EI) was studied in 19 Parkinson's disease (PD) patients after subthalamic deep brain stimulation (STN-DBS) versus 14 nonoperated ones. Operated patients had a significant weight gain (WG, + 9.7 +/- 7 kg) and BMI increase (+ 4.7 kg/m2). The fat mass was higher after STN-DBS. Resting EE (REE; offdrug/ON stimulation) was significantly decreased in STN-DBS patients, while their daily energy expenditure (DEI) was not significantly different. A significant correlation was found among WG, BMI increase, and pre-operative levodopa-equivalent daily dose, their reduction after STN-DBS, and the differential REE related to stimulation and the REE in the offdrug/OFF stimulation condition. In conclusion, STN-DBS in PD induces a significant WG associated with a reduction in REE without DEI adjustment.

OBJECTIVE -The Cockcroft-Gault formula is recommended for the evaluation of renal function in diabetic patients. The more recent Modification of Diet in Renal Disease (MDRD) study equation seems more accurate, but it has not been validated in diabetic patients. This study compares the two methods.RESEARCH DESIGN AND METHODS -In 160 diabetic patients, we compared the Cockcroft-Gault formula and MDRD equation estimations to glomerular filtration rates (GFRs) measured by an isotopic method ( 51 Cr-EDTA) by correlation studies and a Bland-Altman procedure. Their accuracy for the diagnosis of moderately (GFR Ͻ60 ml ⅐ min Ϫ1 ⅐ 1.73 m Ϫ2 ) or severely (GFR Ͻ30 ml ⅐ min Ϫ1 ⅐ 1.73 m Ϫ2 ) impaired renal function were compared with receiver operating characteristic (ROC) curves.RESULTS -Both the Cockcroft-Gault formula (r ϭ 0.74; P Ͻ 0.0001) and MDRD equation (r ϭ 0.81; P Ͻ 0.0001) were well correlated with isotopic GFR. The Bland-Altman procedure revealed a bias for the MDRD equation, which was not the case for the Cockcroft-Gault formula. Analysis of ROC curves showed that the MDRD equation had a better maximal accuracy for the diagnosis of moderate (areas under the curve [AUCs] 0.868 for the Cockcroft-Gault formula and 0.927 for the MDRD equation; P ϭ 0.012) and severe renal failure (AUC 0.883 for the CockcroftGault formula and 0.962 for the MDRD equation; P ϭ 0.0001). In the 87 patients with renal insufficiency, the MDRD equation estimation was better correlated with isotopic GFR (Cockcroft-Gault formula r ϭ 0.57; the MDRD equation r ϭ 0.78; P Ͻ 0.01), and it was not biased as evaluated by the Bland-Altman procedure.CONCLUSIONS -Although both equations have imperfections, the MDRD equation is more accurate for the diagnosis and stratification of renal failure in diabetic patients. Diabetes Care 28:838 -843, 2005D iabetic nephropathy affects 25-40% of diabetic patients (1), and diabetes is the leading cause of endstage renal disease (ESRD) in developed countries (2). Mainly because of the high prevalence and increased life expectancy of type 2 diabetic patients (3), the proportion of patients with both diabetes and ESRD is dramatically growing in developed countries (4). Survival rates are low in such patients because of high cardiovascular risk (5), and medical costs are high (6).The evaluation of renal function is therefore of critical importance in diabetic subjects. Glomerular filtration rate (GFR) is the best measure of overall kidney function in health and disease (7). Serum creatinine concentration is widely used as an indirect marker of GFR, but it is influenced by muscle mass and diet (8). GFR can be directly measured by infusion of external substances such as inulin or 51 Cr-EDTA (9), but these methods are expensive and time consuming. The use of prediction equations to estimate GFR from serum creatinine and other variables (age, sex, race, and body size) is therefore recommended by the National Kidney Foundation for the diagnosis and stratification of chronic kidney diseases (10). According to these guideline...

Patients with Parkinson's disease (PD) often lose weight, but after subthalamic nucleus deep brain stimulation (STN-DBS), they gain weight. We compared daily energy intake (DEI), resting energy expenditure (REE) and substrate oxidation rates (measured by indirect calorimetry) in nineteen STN-DBS-treated patients (Group S), thirteen others on pharmacologic treatment by levodopa (Group L) and eight control subjects. We also determined the acute effects of STN-DBS and levodopa on REE and substrate oxidation rates. STN-DBS treated patients gained 9·7 (SEM 7·1) kg after surgery, whereas patients on pharmacologic treatment lost 3·8 (SEM 10·0) kg since diagnosis. In STN-DBS-treated patients, REE (216·5 %; P,0·001), lipid oxidation (2 27 %; P, 0·05) and protein oxidation (2 46 %; P,0·05) were decreased, whereas glucose oxidation was elevated (þ81 %; P,0·05) as compared to patients on pharmacologic treatment. Levodopa acutely reduced REE (28·3 %; P,0·05) and glucose oxidation (2 37 %; P, 0·01) with a slight hyperglycaemic effect (after levodopa challenge: 5·6 (SEM 0·8) v. before levodopa challenge: 5·3 (SEM 0·6) mmol/l; P,0·01). Switching 'on' STN-DBS acutely reduced REE (217·5 %; P,0·01) and lipid oxidation (2 24 %; P, 0·001) 30 min after starting stimulation. Fasting glycaemia was slightly but significantly reduced (5·4 (SEM 1·4) v. 5·5 (SEM 1·3) mmol/l; P,0·01). After STN-DBS, the normalization of REE and the reduction in lipid and protein oxidation contribute to the restoration of weight. As levodopa decreases glucose oxidation, the reduction in daily dose of levodopa in STN-DBS-treated patients helps prevent the effect of weight gain on glycaemia.

OBJECTIVE -The Cockcroft-Gault and Modification of Diet in Renal Disease (MDRD) equations poorly predict glomerular filtration rate (GFR) decline in diabetic patients. We sought to discover whether new equations based on serum creatinine (the Mayo Clinic Quadratic [MCQ] or reexpressed MDRD equations) or four cystatin C-based equations (glomerular filtration rate estimated via cystatin formula [Cys-eGFR]) were less biased and better predicted GFR changes.RESEARCH DESIGN AND METHODS -In 124 diabetic patients with a large range of isotopic GFR (iGFR) (56.1 Ϯ 35.3 ml/min per 1.73 m 2 [range 5-164]), we compared the performances of the equations before and after categorization in GFR tertiles. A total of 20 patients had a second determination 2 years later.RESULTS -The Cockcroft-Gault equation was the least precise. The MDRD equation was the most precise but the most biased according to the Bland-Altman procedure. By contrast with the MDRD and, to a lesser extent, the MCQ, three of the four Cys-eGFRs were not biased. All equations overestimated the low GFRs, whereas only the MDRD and Rule's Cys-eGFR equations underestimated the high GFRs. For the subjects studied twice, iGFR changed by Ϫ8.5 Ϯ 17.9 ml/min per 1.73 m 2 . GFR changes estimated by the Cockcroft-Gault (Ϫ4.5 Ϯ 6.8) and MDRD (Ϫ5.7 Ϯ 6.2) equations did not correlate with the isotopic changes, whereas new equationpredicted changes did: MCQ: Ϫ8.7 Ϯ 9.4 (r ϭ 0.44, P Ͻ 0.05) and all four Cys-eGFRs: Ϫ6.2 Ϯ 7.4 to Ϫ7.3 Ϯ 8.4 (r ϭ 0.60 to 0.62, all P Ͻ 0.005), such as 100/cystatin-C (r ϭ 0.61, P Ͻ 0.005). CONCLUSIONS -The new predictive equations better estimate GFR than the CockcroftGault equation. Although the MDRD equation remains the most accurate, it poorly predicts GFR decline, as it overestimates low and underestimates high GFRs. This bias is lesser with the MCQ and Cys-eGFR equations, so they better predict GFR changes. 30:1988-1994, 2007 C hronic kidney disease (CKD) is a major health problem worldwide, with dramatically rising incidence and prevalence. Patients with diabetes are particularly affected by this negative development. It is necessary to stratify CKD and estimate its progression because diabetes is the leading cause of end-stage renal disease (1). The National Kidney Foundation guidelines recommend estimating glomerular filtration rate (GFR) in subjects with CKD (2). According to the National Kidney Foundation and the American Diabetes Association, GFR can be estimated in adults by using the Cockcroft-Gault or the Modification of Diet in Renal Disease (MDRD) equations (1,3). Neither of these equations, based on serum creatinine, is highly predictive of GFR. The Cockcroft-Gault equation is less accurate (4), biased by body weight (5), and less robust in patients with poor glycemic control (6). The simplified MDRD equation allows renal function to be classified with acceptable precision and requires only usual information about the patient. However, adjustment may be required to avoid error due to creatinine assays and calibrators (7). Moreov...

No abstract

No abstract

OBJECTIVE -Hyperglycemia increases glomerular filtration rate (GFR), but the influence of HbA 1c (A1C) on GFR and GFR's prediction by recommended equations remains to be determined.RESEARCH DESIGN AND METHODS -In 193 diabetic patients, we searched for an association between A1C and isotopically measured GFR (51Cr-EDTA) and their predictions by the Cockcroft and Gault formula (CG) and the modification of diet in renal disease (MDRD) equation. Their accuracy for the diagnosis of moderate (GFR Ͻ60 ml/min per 1.73 m 2 ) or severe (GFR Ͻ30 ml/min per 1.73 m 2 ) renal failure was compared from receiver operating characteristic (ROC) curves, before and after categorizing the patients as well (A1C Յ8%) or poorly controlled.RESULTS -The mean GFR was 57.0 Ϯ 34.8 ml/min per 1.73 m 2 and was well correlated with both estimations (CG r ϭ 0.75, MDRD r ϭ 0.83; P Ͻ 0.05). The areas under the ROC curves were higher with the MDRD (P Ͻ 0.05). A1C was correlated (P Ͻ 0.001) with the GFR (r ϭ 0.29), MDRD (r ϭ 0.38), CG (r ϭ 0.26), and the absolute differences between the GFR and their CG but not MDRD estimations (r ϭ 0.17, P Ͻ 0.05). Each ϩ1% A1C was associated with ϩ6.0 ml/min per 1.73 m 2 GFR (CG ϩ5.6, MDRD ϩ5.3). After separating well-controlled (n ϭ 88, A1C 7.0 Ϯ 0.7%) and poorly controlled (n ϭ 105, 9.6 Ϯ 1.3%) patients, the diagnostic accuracies were better (P Ͻ 0.05) for the MDRD, except for the diagnosis of moderate renal failure in well-controlled patients (NS).CONCLUSIONS -GFR and its estimations correlate with A1C. Although the relations between GFR and its estimations were not affected by the degree of glucose control, the precision and diagnostic accuracy of the CG formula were diminished for A1C Ͼ8%. The MDRD equation was more accurate and robust in diabetic patients with impaired renal function. Diabetes Care 29:1491-1495, 2006T he Kidney Disease Outcome Quality Initiative guidelines (1) recommend estimating glomerular filtration rate (GFR) in patients with chronic kidney disease using the Cockcroft and Gault formula (CG) (2) or the modification of diet in renal disease (MDRD) study equation (3). This enables stratification of chronic renal failure as moderate (GFR Ͻ60 ml/ min per 1.73 m 2 ) or severe (GFR Ͻ30 ml/min per 1.73 m 2 ). The original MDRD study (3) and more recent ones (4,5) found that the MDRD equation was more accurate than the CG for GFR prediction, although both underestimate GFR in healthy individuals (6).Diabetes is the leading cause of endstage renal disease in the Western world (7). Both the CG and MDRD predictions can be used according to the recent recommendations for clinical practice of the American Diabetes Association (8); some reports favor the MDRD equation for diabetic patients (9,10), while others do not (11,12). Apart from the presence of body weight in the CG calculation, leading to a BMI-related bias and an overestimation for type 2 diabetic patients (13), the impact of glucose control on GFR may be another diabetes patient-specific cause of error.Acute hyperglycemia is known to incr...

In diabetic subjects, the MCQ has a similar diagnostic performance to the MDRD, but it does not underestimate normal GFR, which is an important advantage.