Sophia Zoungas

Severe Hypoglycemia and Risks of Vascular Events and Death

BACKGROUND Severe hypoglycemia may increase the risk of a poor outcome in patients with type 2 diabetes assigned to an intensive glucose-lowering intervention. We analyzed data from a large study of intensive glucose lowering to explore the relationship between severe hypoglycemia and adverse clinical outcomes. METHODS We examined the associations between severe hypoglycemia and the risks of macrovascular or microvascular events and death among 11,140 patients with type 2 diabetes, using Cox proportional-hazards models with adjustment for covariates measured at baseline and after randomization. RESULTS During a median follow-up period of 5 years, 231 patients (2.1%) had at least one severe hypoglycemic episode; 150 had been assigned to intensive glucose control (2.7% of the 5571 patients in that group), and 81 had been assigned to standard glucose control (1.5% of the 5569 patients in that group). The median times from the onset of severe hypoglycemia to the first major macrovascular event, the first major microvascular event, and death were 1.56 years (interquartile range, 0.84 to 2.41), 0.99 years (interquartile range, 0.40 to 2.17), and 1.05 years (interquartile range, 0.34 to 2.41), respectively. During follow-up, severe hypoglycemia was associated with a significant increase in the adjusted risks of major macrovascular events (hazard ratio, 2.88; 95% confidence interval [CI], 2.01 to 4.12), major microvascular events (hazard ratio, 1.81; 95% CI, 1.19 to 2.74), death from a cardiovascular cause (hazard ratio, 2.68; 95% CI, 1.72 to 4.19), and death from any cause (hazard ratio, 2.69; 95% CI, 1.97 to 3.67) (P<0.001 for all comparisons). Similar associations were apparent for a range of nonvascular outcomes, including respiratory, digestive, and skin conditions (P<0.01 for all comparisons). No relationship was found between repeated episodes of severe hypoglycemia and vascular outcomes or death. CONCLUSIONS Severe hypoglycemia was strongly associated with increased risks of a range of adverse clinical outcomes. It is possible that severe hypoglycemia contributes to adverse outcomes, but these analyses indicate that hypoglycemia is just as likely to be a marker of vulnerability to such events. (Funded by Servier and the National Health and Medical Research Council of Australia; ClinicalTrials.gov number, NCT00145925.).

Albuminuria and Kidney Function Independently Predict Cardiovascular and Renal Outcomes in Diabetes

There are limited data regarding whether albuminuria and reduced estimated GFR (eGFR) are separate and independent risk factors for cardiovascular and renal events among individuals with type 2 diabetes. The Action in Diabetes and Vascular disease: preterAx and diamicroN-MR Controlled Evaluation (ADVANCE) study examined the effects of routine BP lowering on adverse outcomes in type 2 diabetes. We investigated the effects of urinary albumin-to-creatinine ratio (UACR) and eGFR on the risk for cardiovascular and renal events in 10,640 patients with available data. During an average 4.3-yr follow-up, 938 (8.8%) patients experienced a cardiovascular event and 107 (1.0%) experienced a renal event. The multivariable-adjusted hazard ratio for cardiovascular events was 2.48 (95% confidence interval 1.74 to 3.52) for every 10-fold increase in baseline UACR and 2.20 (95% confidence interval 1.09 to 4.43) for every halving of baseline eGFR, after adjustment for regression dilution. There was no evidence of interaction between the effects of higher UACR and lower eGFR. Patients with both UACR >300 mg/g and eGFR <60 ml/min per 1.73 m(2) at baseline had a 3.2-fold higher risk for cardiovascular events and a 22.2-fold higher risk for renal events, compared with patients with neither of these risk factors. In conclusion, high albuminuria and low eGFR are independent risk factors for cardiovascular and renal events among patients with type 2 diabetes.

Effect of lowering blood pressure on cardiovascular events and mortality in patients on dialysis: a systematic review and meta-analysis of randomised controlled trials

Summary Background Patients undergoing dialysis have a substantially increased risk of cardiovascular mortality and morbidity. Although several trials have shown the cardiovascular benefits of lowering blood pressure in the general population, there is uncertainty about the efficacy and tolerability of reducing blood pressure in patients on dialysis. We did a systematic review and meta-analysis to assess the effect of blood pressure lowering in patients on dialysis. Methods We systematically searched Medline, Embase, and the Cochrane Library database for trials reported between 1950 and November, 2008, without language restriction. We extracted a standardised dataset from randomised controlled trials of blood pressure lowering in patients on dialysis that reported cardiovascular outcomes. Meta-analysis was done with a random effects model. Findings We identified eight relevant trials, which provided data for 1679 patients and 495 cardiovascular events. Weighted mean systolic blood pressure was 4·5 mm Hg lower and diastolic blood pressure 2·3 mm Hg lower in actively treated patients than in controls. Blood pressure lowering treatment was associated with lower risks of cardiovascular events (RR 0·71, 95% CI 0·55–0·92; p=0·009), all-cause mortality (RR 0·80, 0·66–0·96; p=0·014), and cardiovascular mortality (RR 0·71, 0·50–0·99; p=0·044) than control regimens. The effects seem to be consistent across a range of patient groups included in the studies. Interpretation Treatment with agents that lower blood pressure should routinely be considered for individuals undergoing dialysis to reduce the very high cardiovascular morbidity and mortality rate in this population. Funding National Health and Medical Research Council of Australia Program.

Follow-up of Blood-Pressure Lowering and Glucose Control in Type 2 Diabetes

BACKGROUND In the Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation (ADVANCE) factorial trial, the combination of perindopril and indapamide reduced mortality among patients with type 2 diabetes, but intensive glucose control, targeting a glycated hemoglobin level of less than 6.5%, did not. We now report results of the 6-year post-trial follow-up. METHODS We invited surviving participants, who had previously been assigned to perindopril-indapamide or placebo and to intensive or standard glucose control (with the glucose-control comparison extending for an additional 6 months), to participate in a post-trial follow-up evaluation. The primary end points were death from any cause and major macrovascular events. RESULTS The baseline characteristics were similar among the 11,140 patients who originally underwent randomization and the 8494 patients who participated in the post-trial follow-up for a median of 5.9 years (blood-pressure-lowering comparison) or 5.4 years (glucose-control comparison). Between-group differences in blood pressure and glycated hemoglobin levels during the trial were no longer evident by the first post-trial visit. The reductions in the risk of death from any cause and of death from cardiovascular causes that had been observed in the group receiving active blood-pressure-lowering treatment during the trial were attenuated but significant at the end of the post-trial follow-up; the hazard ratios were 0.91 (95% confidence interval [CI], 0.84 to 0.99; P=0.03) and 0.88 (95% CI, 0.77 to 0.99; P=0.04), respectively. No differences were observed during follow-up in the risk of death from any cause or major macrovascular events between the intensive-glucose-control group and the standard-glucose-control group; the hazard ratios were 1.00 (95% CI, 0.92 to 1.08) and 1.00 (95% CI, 0.92 to 1.08), respectively. CONCLUSIONS The benefits with respect to mortality that had been observed among patients originally assigned to blood-pressure-lowering therapy were attenuated but still evident at the end of follow-up. There was no evidence that intensive glucose control during the trial led to long-term benefits with respect to mortality or macrovascular events. (Funded by the National Health and Medical Research Council of Australia and others; ADVANCE-ON ClinicalTrials.gov number, NCT00949286.).

Combined Effects of Routine Blood Pressure Lowering and Intensive Glucose Control on Macrovascular and Microvascular Outcomes in Patients With Type 2 Diabetes: New results from the ADVANCE trial

OBJECTIVE To assess the magnitude and independence of the effects of routine blood pressure lowering and intensive glucose control on clinical outcomes in patients with long-standing type 2 diabetes. RESEARCH DESIGN AND METHODS This was a multicenter, factorial randomized trial of perindopril-indapamide versus placebo (double-blind comparison) and intensive glucose control with a gliclazide MR–based regimen (target A1C ≤6.5%) versus standard glucose control (open comparison) in 11,140 participants with type 2 diabetes who participated in the Action in Diabetes and Vascular Disease: Preterax and Diamicron MR Controlled Evaluation (ADVANCE) trial. Annual event rates and risks of major macrovascular and microvascular events considered jointly and separately, renal events, and death during an average 4.3 years of follow-up were assessed, using Cox proportional hazards models. RESULTS There was no interaction between the effects of routine blood pressure lowering and intensive glucose control for any of the prespecified clinical outcomes (all P > 0.1): the separate effects of the two interventions for the renal outcomes and death appeared to be additive on the log scale. Compared with neither intervention, combination treatment reduced the risk of new or worsening nephropathy by 33% (95% CI 12–50%, P = 0.005), new onset of macroalbuminuria by 54% (35–68%, P < 0.0001), and new onset of microalbuminuria by 26% (17–34%). Combination treatment was associated with an 18% reduction in the risk of all-cause death (1–32%, P = 0.04). CONCLUSIONS The effects of routine blood pressure lowering and intensive glucose control were independent of one another. When combined, they produced additional reductions in clinically relevant outcomes.

Association of HbA1c levels with vascular complications and death in patients with type 2 diabetes: evidence of glycaemic thresholds

Aims/hypothesisThere is conflicting evidence regarding appropriate glycaemic targets for patients with type 2 diabetes. Here, we investigate the relationship between HbA1c and the risks of vascular complications and death in such patients.MethodsEleven thousand one hundred and forty patients were randomised to intensive or standard glucose control in the Action in Diabetes and Vascular disease: Preterax and Diamicron Modified Release Controlled Evaluation (ADVANCE) trial. Glycaemic exposure was assessed as the mean of HbA1c measurements during follow-up and prior to the first event. Adjusted risks for each HbA1c decile were estimated using Cox models. Possible differences in the association between HbA1c and risks at different levels of HbA1c were explored using linear spline models.ResultsThere was a non-linear relationship between mean HbA1c during follow-up and the risks of macrovascular events, microvascular events and death. Within the range of HbA1c studied (5.5–10.5%), there was evidence of ‘thresholds’, such that below HbA1c levels of 7.0% for macrovascular events and death, and 6.5% for microvascular events, there was no significant change in risks (all p > 0.8). Above these thresholds, the risks increased significantly: every 1% higher HbA1c level was associated with a 38% higher risk of a macrovascular event, a 40% higher risk of a microvascular event and a 38% higher risk of death (all p < 0.0001).Conclusions/interpretationIn patients with type 2 diabetes, HbA1c levels were associated with lower risks of macrovascular events and death down to a threshold of 7.0% and microvascular events down to a threshold of 6.5%. There was no evidence of lower risks below these levels but neither was there clear evidence of harm.Trial Registration:ClinicalTrial.gov NCT00145925Funding:Servier and the National Health and Medical Research Council of Australia (project grant ID 211086 and programme grant IDs 358395 and 571281)

Intensive glucose control improves kidney outcomes in patients with type 2 diabetes

The effect of intensive glucose control on major kidney outcomes in type 2 diabetes remains unclear. To study this, the ADVANCE trial randomly assigned 11,140 participants to an intensive glucose-lowering strategy (hemoglobin A1c target 6.5% or less) or standard glucose control. Treatment effects on end-stage renal disease ((ESRD), requirement for dialysis or renal transplantation), total kidney events, renal death, doubling of creatinine to above 200 μmol/l, new-onset macroalbuminuria or microalbuminuria, and progression or regression of albuminuria, were then assessed. After a median of 5 years, the mean hemoglobin A1c level was 6.5% in the intensive group, and 7.3% in the standard group. Intensive glucose control significantly reduced the risk of ESRD by 65% (20 compared to 7 events), microalbuminuria by 9% (1298 compared to 1410 patients), and macroalbuminuria by 30% (162 compared to 231 patients). The progression of albuminuria was significantly reduced by 10% and its regression significantly increased by 15%. The results were almost identical in analyses taking account of potential competing risks. The number of participants needed to treat over 5 years to prevent one ESRD event ranged from 410 in the overall study to 41 participants with macroalbuminuria at baseline. Thus, improved glucose control will improve major kidney outcomes in patients with type 2 diabetes.

Systematic review: sodium bicarbonate treatment regimens for the prevention of contrast-induced nephropathy

In this review of 23 trials on whether sodium bicarbonate reduced risk for contrast-induced nephropathy (CIN) more than saline, the pooled relative risk for CIN was 0.62 (95% CI, 0.45 to 0.86). How...

Aspirin is beneficial in hypertensive patients with chronic kidney disease: a post-hoc subgroup analysis of a randomized controlled trial.

OBJECTIVES The purpose of this study was to determine the benefit and risk associated with antiplatelet therapy in the chronic kidney disease (CKD) population. BACKGROUND Cardiovascular and possibly bleeding risks are elevated in patients with CKD. The balance of benefit and harm associated with antiplatelet therapy remains uncertain. METHODS The HOT (Hypertension Optimal Treatment) study randomly assigned participants with diastolic hypertension to aspirin (75 mg) or placebo. Study treatment effects were calculated using univariate proportional hazards regression models stratified by baseline estimated glomerular filtration rate (eGFR) with trends tested by adding interaction terms. End points included major cardiovascular events, total mortality, and major bleeding. RESULTS The study included 18,597 participants treated for 3.8 years. Baseline eGFR was < 60 ml/min/1.73 m(2) in 3,619 participants. Major cardiovascular events were reduced by 9% (95% confidence interval [CI]: -9% to 24%), 15% (95% CI: -17% to 39%), and 66% (95% CI: 33% to 83%) for patients with baseline eGFR of ≥ 60, 45 to 59, and < 45 ml/min/1.73 m(2), respectively (p trend = 0.03). Total mortality was reduced by 0% (95% CI: -20% to 17%), 11% (95% CI: -31% to 40%), and 49% (95% CI: 6% to 73%), respectively (p trend = 0.04). Major bleeding events were nonsignificantly greater with lower eGFR (hazard ratio [HR]: 1.52 [95% CI: 1.11 to 2.08], HR: 1.70 [95% CI: 0.74 to 3.88], and HR: 2.81 [95% CI: 0.92 to 8.84], respectively; p trend = 0.30). Among every 1,000 persons with eGFR < 45 ml/min/1.73 m(2) treated for 3.8 years, 76 major cardiovascular events and 54 all-cause deaths will be prevented while 27 excess major bleeds will occur. CONCLUSIONS Aspirin therapy produces greater absolute reduction in major cardiovascular events and mortality in hypertensive patients with CKD than with normal kidney function. An increased risk of major bleeding appears to be outweighed by the substantial benefits.

Cognitive function and risks of cardiovascular disease and hypoglycaemia in patients with type 2 diabetes: the Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation (ADVANCE) trial

Aims/hypothesisThe relationship between cognitive function, cardiovascular disease and premature death is not well established in patients with type 2 diabetes. We assessed the effects of cognitive function in 11,140 patients with type 2 diabetes who participated in the Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation (ADVANCE) trial. Furthermore, we tested whether level of cognitive function altered the beneficial effects of the BP-lowering and glycaemic-control regimens in the trial.MethodsCognitive function was assessed using the Mini Mental State Examination at baseline, and defined by scores 28-30 (‘normal’, n = 8,689), 24-27 (‘mild dysfunction’, n = 2,231) and <24 (‘severe dysfunction’, n = 212). Risks of major cardiovascular events, death and hypoglycaemia and interactions with treatment were assessed using Cox proportional hazards analysis.ResultsRelative to normal function, both mild and severe cognitive dysfunction significantly increased the multiple-adjusted risks of major cardiovascular events (HR 1.27, 95% CI 1.11–1.46 and 1.42, 95% CI 1.01–1.99; both p < 0.05), cardiovascular death (1.41, 95% CI 1.16–1.71 and 1.56, 95% CI 0.99–2.46; both p ≤ 0.05) and all-cause death (1.33, 95% CI 1.16–1.54 and 1.50, 95% CI 1.06–2.12; both p < 0.03). Severe, but not mild, cognitive dysfunction increased the risk of severe hypoglycaemia (HR 2.10, 95% CI 1.14–3.87; p = 0.018). There was no evidence of heterogeneity of treatment effects on cardiovascular outcomes in subgroups defined by cognitive function at baseline.Conclusions/interpretationCognitive dysfunction is an independent predictor of clinical outcomes in patients with type 2 diabetes, but does not modify the effects of BP lowering or glucose control on the risks of major cardiovascular events.Trial registration:ClinicalTrials.gov NCT00145925Funding:Supported by grants from Servier and from the National Health and Medical Research Council of Australia.