Sabin Shurraw

Guidelines for the management of chronic kidney disease

New guidelines for the management of chronic kidney disease have been developed by the Canadian Society of Nephrology (Appendix 1 contains the full-text guidelines; available at [www.cmaj.ca/cgi/content/full/179/11/1154/DC1][1]). These guidelines describe key aspects of the management of chronic

Association Between Glycemic Control and Adverse Outcomes in People With Diabetes Mellitus and Chronic Kidney Disease: A Population-Based Cohort Study

BACKGROUND Better glycemic control as reflected by lower hemoglobin A(1c) (HbA(1c)) level may prevent or slow progression of nephropathy in people with diabetes mellitus (DM). Whether a lower HbA(1c) level improves outcomes in people with DM and chronic kidney disease (CKD) is unknown. METHODS From all people with serum creatinine measured as part of routine care in a single Canadian province from 2005 through 2006, we identified those with CKD based on laboratory data (estimated glomerular filtration rate [eGFR], <60.0 mL/min/1.73 m(2)]) and DM using a validated algorithm applied to hospitalization and claims data. Patients were classified based on their first HbA(1c) measurement; Cox regression models were used to assess independent associations between HbA(1c) level and 5 study outcomes (death, progression of kidney disease based on a doubling of serum creatinine level, or new end-stage renal disease [ESRD], cardiovascular events, all-cause hospitalization). RESULTS We identified 23,296 people with DM and an eGFR lower than 60.0 mL/min/1.73 m(2). The median HbA(1c) level was 6.9% (range, 2.8%-20.0%), and 11% had an HbA(1c) value higher than 9%. Over the median follow-up period of 46 months, 3665 people died, and 401 developed ESRD. Regardless of baseline eGFR, a higher HbA(1c) level was strongly and independently associated with excess risk of all 5 outcomes studied (P < .001 for all comparisons). However, the association with mortality was U-shaped, with increases in the risk of mortality apparent at HbA(1c) levels lower than 6.5% and higher than 8.0%. The increased risk of ESRD associated with a higher HbA(1c) level was attenuated at a lower baseline eGFR (P value for interaction, <.001). Specifically, among those with an eGFR of 30.0 to 59.9 mL/min/1.73 m(2), the risk of ESRD was increased by 22% and 152% in patients with HbA(1c) levels of 7% to 9% and higher than 9%, respectively, compared with patients with an HbA(1c) level lower than 7% (P < .001), whereas corresponding increases were 3% and 13%, respectively, in those with an eGFR of 15.0 to 29.9 mL/min/1.73 m(2). CONCLUSIONS A hemoglobin A(1c) level higher than 9% is common in people with non-hemodialysis-dependent CKD and is associated with markedly worse clinical outcomes; lower levels of HbA(1c) (<6.5%) also seemed to be associated with excess mortality. The excess risk of kidney failure associated with a higher HbA(1c) level was most pronounced among people with better kidney function. These findings suggest that appropriate and timely control of HbA(1c) level in people with DM and CKD may be more important than previously realized, but suggest also that intensive glycemic control (HbA(1c) level <6.5%) may be associated with increased mortality.

Glycemic Control and the Risk of Death in 1,484 Patients Receiving Maintenance Hemodialysis

BACKGROUND It is controversial whether tighter glycemic control is associated with better clinical outcomes in people with kidney failure. We aim to determine whether worse glycemic control, measured using serum glucose and hemoglobin A(1c) (HbA(1c)) levels, is independently associated with higher mortality in patients undergoing maintenance hemodialysis. STUDY DESIGN Retrospective cohort study. SETTING & PARTICIPANTS 1,484 patients starting maintenance hemodialysis therapy in Alberta, Canada, between 2001 and 2007. PREDICTOR Serum glucose and HbA(1c) levels. OUTCOME All-cause mortality. MEASUREMENTS Monthly casual glucose levels from specimens drawn immediately before the first dialysis treatment were averaged over 3 months before and after hemodialysis therapy initiation. Similarly, monthly HbA(1c) values in patients with or at risk of diabetes were averaged. RESULTS Overall, median age was 66 years, 41% were women, 75% were white, and 55% had diabetes. All-cause mortality during 8 years (median, 1.5 years) was 43%; it was 49% in those with diabetes. There was no relation between average glucose level and mortality in unadjusted analysis (HR, 1.00 per 18 mg/dL [1 mmol/L]; P = 0.4) or after adjustment for confounders (HR, 0.98 per 18 mg/dL; 95% CI, 0.96-1.01; P = 0.2). Higher HbA(1c) level was not associated with mortality when analyzed in the unadjusted analysis (HR, 1.01 per 1% HbA(1c); P = 0.9) or after adjustment for confounders (HR, 0.98 per 1% HbA1c; 95% CI, 0.88-1.08; P = 0.7). Results were similar when HbA(1c) values were divided into prespecified categories (adjusted P > 0.6 for trend). Markers of malnutrition-inflammation (albumin, hemoglobin, and white blood cell values) or the presence of diabetes did not influence the relation between glycemic control and death (all P for interaction > 0.2). LIMITATIONS Registry data; casual serum glucose measurements; HbA(1c) values available for only a subset of participants. CONCLUSIONS Higher casual glucose and HbA(1c) levels were not associated with mortality in maintenance hemodialysis patients with or without diabetes. This may have implications for recommended glycemic targets, quality indicators, and how best to assess glycemic control in this high-risk population.

Intensive glycemic control in type 2 diabetics at high cardiovascular risk: do the benefits justify the risks?

Perkovic et al. use novel data from the ADVANCE study to report on the potential renal benefits of standard glycemic control, compared with intensive glycemic control (mean hemoglobin A1c 7.3 and 6.5%, respectively). Intensive glycemic control reduced the risk of new-onset microalbuminuria, new-onset macroalbuminuria, and progression of albuminuria. The risk of end-stage renal disease was also reduced in patients treated with intensive glycemic control, although the number of events was small.