Changes in renal function during acute insulin-induced hypoglycaemia in patients with type 1 diabetes

An evidence-based practice-oriented review focusing on canagliflozin in the management of type 2 diabetes

Caring for patients with type 2 diabetes mellitus (T2DM) has entered an era with many recent additions to the regimens used to clinically control their hyperglycemia. The most recent class of agents approved by the Food and Drug Administration (FDA) for T2DM is the sodium–glucose-linked transporter type 2 (SGLT2) inhibitors, which work principally in the proximal tubule of the kidney to block filtered glucose reabsorption. In the few years attending this new class arrival in the market, there has been a great deal of interest generated by the novel mechanism of action of SGLT2 inhibitors and by recent large outcome trials suggesting benefit on important clinical outcomes such as death, cardiovascular disease and kidney disease progression. In this review, we focus on canagliflozin, the first-in-class marketed SGLT2 inhibitor in the USA. In some cases, we included data from other SGLT2 inhibitors, such as outcomes in clinical trials, important insights on clinical features and benefits, and adverse effects. These agents represent a fundamentally different way of controlling blood glucose and for the first time in T2DM care to offer the opportunity to reduce glucose, blood pressure, and weight with effects sustained for at least 2 years. Important side effects include genital mycotic infections and the potential for orthostatic hypotension and rare instances of normoglycemic ketoacidosis. Active ongoing clinical trials promise to deepen our experience with the potential benefits, as well as the clinical risks attending the use of this new group of antidiabetic agents.

Accelerated decline of renal function in type 2 diabetes following severe hypoglycemia

AIMS

This study aimed to evaluate whether the pronounced elevation in blood pressure during severe hypoglycemia is associated with subsequent renal insufficiency.

METHODS

We conducted a 3-year cohort study to assess the clinical course of renal function in type 2 diabetes patients with or without blood pressure surge during severe hypoglycemia.

RESULTS

Of 111 type 2 diabetes patients with severe hypoglycemia, 76 exhibited an extremely high systolic blood pressure before treatment, whereas 35 demonstrated no such increase (179.1 ± 27.7 mmHg vs. 131.1 ± 20.2 mmHg, P<0.001). At 12h after treatment, systolic blood pressure did not differ significantly (131.5 ± 30.7 mmHg vs. 123.5 ± 20.7 mmHg; P=0.39). The estimated glomerular filtration rate (GFR) before and at the time of severe hypoglycemia did not significantly differ between both groups. A multivariate Cox proportional hazards regression analysis revealed that blood pressure surge during severe hypoglycemia was independently associated with a composite outcome of a more than 15 mL/min/1.73 m(2) decrease in the estimated GFR and initiation of chronic dialysis (hazard ratio, 2.68; 95% confidence interval, 1.12-6.38; P=0.02).

CONCLUSIONS

Renal function after severe hypoglycemia was significantly worse in type 2 diabetes patients with blood pressure surge during severe hypoglycemia than those without blood pressure surge.

Association of hypoglycemia with incident chronic kidney disease in patients with type 2 diabetes: a nationwide population-based study

This article aims to investigate the long-term risk of incident chronic kidney disease (CKD) in type 2 diabetes mellitus (T2DM) patients with hypoglycemia.This nationwide, population-based, propensity score (PS)-matched cohort study involved 2 cohorts: a hypoglycemic cohort and a matched cohort without hypoglycemia. Data from 1.3 million patients with newly diagnosed T2DM between 2000 and 2010 were extracted from Taiwan's National Health Insurance Research Database. Hypoglycemic events were collected using inpatient, outpatient, and emergency department diagnoses. Patients aged <20 years and those with previous histories of CKD were excluded. The association between hypoglycemia and subsequent CKD risk in patients with T2DM was examined using Cox regression analysis after PS matching.During the mean follow-up period of 4.2 years, a total of 15,036 (1.7 %) patients experienced at least 1 episode of hypoglycemia and 15,036 matched controls without hypoglycemia were identified among 906,368 eligible patients. The incidence rates of subsequent CKD were 26.1 and 14.8 events per 1000 person-years in the hypoglycemic and matched cohorts, respectively. The hazard ratio (HR) of hypoglycemia for incident CKD was 1.77 (95% confidence interval [CI], 1.63-1.92; P < 0.001). Compared with those without hypoglycemia, HRs for 1 to 3 and ≥4 episodes of hypoglycemia for CKD were 1.65 (95% CI, 1.50-1.81) and 1.75 (95% CI, 1.34-2.29), respectively (P for trend <0.001).Our study supports the association of hypoglycemia with CKD development among patients with T2DM, possibly in a dose-dependent relationship.

SGLT-2 inhibitors and cardiovascular risk: proposed pathways and review of ongoing outcome trials

Given the multi-faceted pathogenesis of atherosclerosis in type 2 diabetes mellitus (T2DM), it is likely that interventions to mitigate this risk must address cardiovascular (CV) risk factors beyond glucose itself. Sodium glucose cotransporter-2 (SGLT-2) inhibitors are newer antihyperglycaemic agents with apparent multiple effects. Inherent in their mode of action to decrease glucose reabsorption by the kidneys by increasing urinary glucose excretion, these agents improve glycaemic control independent of insulin secretion with a low risk of hypoglycaemia. In this review, we outline those CV risk factors that this class appears to influence and provide the design features and trial characteristics of six ongoing outcome trials involving more than 41,000 individuals with T2DM. Those risk factors beyond glucose that can potentially be modulated positively with SGLT-2 inhibitors include blood pressure, weight, visceral adiposity, hyperinsulinaemia, arterial stiffness, albuminuria, circulating uric acid levels and oxidative stress. On the other hand, small increases in low-density lipoprotein (LDL)-cholesterol levels have also been observed for the class, which theoretically might offset some of these benefits. The potential translational impact of these effects is being tested with outcome trials, also reviewed in this article, powered to assess both macrovascular as well as certain microvascular outcomes in T2DM. These are expected to begin to report in late 2015.

Improved glucose control with weight loss, lower insulin doses, and no increased hypoglycemia with empagliflozin added to titrated multiple daily injections of insulin in obese inadequately controlled type 2 diabetes

OBJECTIVE

We investigated the efficacy and safety of the sodium glucose cotransporter 2 inhibitor, empagliflozin, added to multiple daily injections of insulin (MDI insulin) in obese patients with type 2 diabetes mellitus (T2DM).

RESEARCH DESIGN AND METHODS

Patients inadequately controlled on MDI insulin ± metformin (mean HbA1c 8.3% [67 mmol/mol]; BMI 34.8 kg/m(2); insulin dose 92 international units/day) were randomized and treated with once-daily empagliflozin 10 mg (n = 186), empagliflozin 25 mg (n = 189), or placebo (n = 188) for 52 weeks. Insulin dose was to remain stable in weeks 1-18, adjusted to meet glucose targets in weeks 19-40, then stable in weeks 41-52. The primary end point was change from baseline in HbA1c at week 18. Secondary end points were changes from baseline in insulin dose, weight, and HbA1c at week 52.

RESULTS

Adjusted mean ± SE changes from baseline in HbA1c were -0.50 ± 0.05% (-5.5 ± 0.5 mmol/mol) for placebo versus -0.94 ± 0.05% (-10.3 ± 0.5 mmol/mol) and -1.02 ± 0.05% (-11.1 ± 0.5 mmol/mol) for empagliflozin 10 mg and empagliflozin 25 mg, respectively, at week 18 (both P < 0.001). At week 52, further reductions with insulin titration resulted in changes from baseline in HbA1c of -0.81 ± 0.08% (-8.9 ± 0.9 mmol/mol), -1.18 ± 0.08% (-12.9 ± 0.9 mmol/mol), and -1.27 ± 0.08% (-13.9 ± 0.9 mmol/mol) with placebo, empagliflozin 10 mg, and empagliflozin 25 mg, respectively, and final HbA1c of 7.5% (58 mmol/mol), 7.2% (55 mmol/mol), and 7.1% (54 mmol/mol), respectively. More patients attained HbA1c <7% (<53 mmol/mol) with empagliflozin (31-42%) versus placebo (21%; both P < 0.01). Empagliflozin 10 mg and empagliflozin 25 mg reduced insulin doses (-9 to -11 international units/day) and weight (-2.4 to -2.5 kg) versus placebo (all P < 0.01) at week 52.

CONCLUSIONS

In obese, difficult-to-treat patients with T2DM inadequately controlled on high MDI insulin doses, empagliflozin improved glycemic control and reduced weight without increasing the risk of hypoglycemia and with lower insulin requirements.

Presence of macroalbuminuria predicts severe hypoglycemia in patients with type 2 diabetes: a 10-year follow-up study

OBJECTIVE

We investigated the factors that might influence the development of severe hypoglycemia in patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS

From January 2000 to December 2002, patients with type 2 diabetes aged 25-75 years without chronic kidney disease (estimated glomerular filtration rate ≥60 mL/min/1.73 m(2)) were consecutively recruited (n = 1,217) and followed-up in January 2011 and May 2012. Severe hypoglycemia (SH) was defined as an event requiring the assistance of another person to actively administer glucose, hospitalization, or medical care in an emergency department. We used Cox proportional hazard regression analysis to test the association between SH episodes and potential explanatory variables.

RESULTS

After a median 10.4 years of follow-up, 111 (12.6%) patients experienced 140 episodes of SH, and the incidence was 1.55 per 100 patient-years. Mean age and duration of diabetes were 55.3 ± 9.8 and 9.8 ± 6.5 years, respectively. The incidence of SH events was higher in older patients (P < 0.001), in those with a longer duration of diabetes (P < 0.001), in those who used insulin (P < 0.001) and sulfonylurea (P = 0.003), and in those who had macroalbuminuria (P < 0.001) at baseline. Cox hazard regression analysis revealed that SH was associated with longer duration of diabetes and the presence of macroalbuminuria (normoalbuminuria versus macroalbuminuria: hazard ratio, 2.52; 95% CI 1.31-4.84; P = 0.006).

CONCLUSIONS

The development of SH was independently associated with duration of diabetes and presence of macroalbuminuria, even with normal renal function in patients with type 2 diabetes.

An examination of the covariability of subclinical albuminuria in insulin-dependent diabetes mellitus: implications for monitoring microalbuminuria

We examined the covariability of subclinical albuminuria in a cohort of 160 insulin-dependent diabetics who underwent simultaneous measurements of overnight urinary albumin excretion rate (UAV) and several clinical variables on 7 occasions over a period of 18 months. After allowing for within-patient correlation between visits, significant within-patient associations were found between UAV and variations in tobacco consumption (regression coefficient = 0.006, S.E. = 0.002, P = 0.02), insulin dose (regression coefficient = 0.003, S.E. = 0.001, P = 0.01) and creatinine clearance (regression coefficient = 0.776, S.E. = 0.047, P < 0.0001); the association between UAV and creatinine clearance was not influenced by adjusting for urine flow rate. No significant associations were found between UAV and changes in blood pressure, glycaemic control or other variables. We then focused on 33 patients with intermittent microalbuminuria, defined as a UAV > 30 micrograms/min on at least one occasion, but not exceeding 3 consecutive occasions. These patients had a total of 52 episodes of microalbuminuria which were significantly associated at the 5% level with increases in creatinine clearance (P = 0.02), but not with changes in other variables. Our findings did not differ in patients with intermittent microalbuminuria defined with reference to a cut-off UAV of 20 micrograms/min. We conclude that changes in glomerular filtration rate (as reflected by creatinine clearance) may partly account for the within-patient variability in subclinical albuminuria in insulin-dependent diabetics, and that variables routinely measured in the clinic are not useful for deciding when to monitor patients for microalbuminuria.