The impact of the angiotensin-converting enzyme insertion/deletion polymorphism on severe hypoglycemia in Type 2 diabetes

High one-year mortality following hospitalization for severe hypoglycemia among patients with diabetes mellitus: findings of a retrospective cohort study at an acute tertiary care hospital in Singapore

OBJECTIVES

Little is known about the 1-year short-term mortality rate following hospital admissions with severe hypoglycemia. This study aimed to determine the factors associated with increased 1-year mortality rate following hospitalization in diabetes patients admitted with severe hypoglycemia to the Singapore General Hospital.

METHODS

Clinical, biochemical, and 1-year mortality data from diabetes patients who were admitted with severe hypoglycemia in the year 2014 were extracted from institutional medical records. Patients who passed away during the episode of admissions with severe hypoglycemia were excluded from the analysis. The clinical and biochemical factors between patients who survived and those who did not survive within 1 year following admission were compared using logistic regression analysis.

RESULTS

Three hundred and four patients (181 female and 123 male) were admitted with severe hypoglycemia in 2014, and the mean capillary blood glucose on admission was 2.3 ± 0.7 mmol/L. Sixty-three (20.7%) patients died within 1-year post-discharge from the hospital. Compared with patients who survived 1-year post-discharge from the hospital, non-survivors were older (69.3 ± 11.0 vs 75.5 ± 11.2 years, p < .001), had longer lengths of stay (LOS) (5.0 ± 7.4 vs 9.0 ± 12.8 days, p = .02), and had a higher Charlson Comorbidity Index (CCI) (4.1 ± 1.9 vs 5.9 ± 2.4, p < .001). Factors associated with increased 1-year mortality risk were age (odds ratio [OR] = 1.06; 95% confidence interval [CI] = 1.03-1.09, p < .01), LOS in hospital (OR = 1.01; 95% CI = 1.01-1.08, p < .01), and CCI (OR = 1.51; 95% CI = 1.31-1.75, p < .01), respectively.

CONCLUSIONS

Older diabetes patients with more comorbidities and longer LOS were at increased risk of dying within a year of discharge after hospitalization with severe hypoglycemia. Admission with severe hypoglycemia has important prognostic implications. Healthcare professionals should address hypoglycemia and other health issues during the hospital admissions.

Drug-induced hypoglycaemia in type 2 diabetes

INTRODUCTION

Hypoglycaemia is a side effect caused by some therapies for type 2 diabetes, which can cause physical, social and psychological harm. Hypoglycaemia also prevents attainment of treatment goals and satisfactory glycaemic control.

AREAS COVERED

The risk of hypoglycaemia associated with commonly prescribed therapies, including metformin, sulphonylureas, dipeptidyl peptidase-4 enzyme (DPP-4) inhibitors, glucagon-like peptide-1 (GLP-1) agonists and thiazolidinediones, is reviewed in this paper (insulin-induced hypoglycaemia is not included). Other medications that are frequently co-prescribed in type 2 diabetes are also discussed, including anti-hypertensive drugs, antibiotics and fibrates, along with various important patient-related risk factors.

EXPERT OPINION

Hypoglycaemia is a common and potentially dangerous side effect of some medications used for type 2 diabetes. The risk of hypoglycaemia should always be considered when selecting and implementing a therapy, with a focus on the individual. Future research into new therapies should measure the frequency of hypoglycaemia prospectively and accurately. Hypoglycaemia has been shown to be a potentially life-threatening metabolic stress; therefore therapies that effectively manage diabetes without the risk of hypoglycaemia are likely to be favoured in the future.

Angiotensin-converting enzyme insertion/deletion polymorphism and severe hypoglycemia complicating type 2 diabetes: the Fremantle Diabetes Study

AIMS/HYPOTHESES

The aim of this study was to determine whether the angiotensin-converting enzyme (ACE) gene I/D polymorphisms independently predict severe hypoglycemia in community-dwelling type 2 patients.

METHODS

Six hundred and two patients who were ACE genotyped at baseline and assessed in 1998 were followed up to the end of June 2006. Severe hypoglycemia was defined as that requiring documented health service use as the primary diagnosis. Cox proportional hazards modeling was used to determine the predictors of first episode and zero-inflated negative binomial regression modeling identified predictors of frequency.

RESULTS

Forty-nine patients (8.1%) experienced 63 episodes of severe hypoglycemia. After adjusting for previously identified significant independent predictors of time to first episode, both ACE DD genotype and ACE inhibitor therapy, but not their interaction, added to the model [hazard ratio (95% confidence interval): 2.34 (1.29-4.26), P = 0.006, and 1.77 (0.99-3.13), P = 0.052, respectively]. Similarly, after adjusting for previously identified risk factors for multiple episodes of severe hypoglycemia, ACE DD genotype was independently associated with increased risk [incidence relative risk (95% confidence interval): 1.80 (1.00-3.24), P = 0.050].

CONCLUSIONS/INTERPRETATION

ACE DD genotype was associated with an approximately 2-fold increased risk of the first episode of severe hypoglycemia and its subsequent frequency in well-characterized patients with type 2 diabetes. Consistent with previous case-control studies, ACE inhibitor therapy was a weak predictor of severe hypoglycemia. ACE I/D genotyping might provide useful adjunctive prognostic information when intensive glycemic control measures are contemplated.

Hypoglycemia, S-ACE and ACE genotypes in a Danish nationwide population of children and adolescents with type 1 diabetes

OBJECTIVE

High S-ACE levels have been shown to predispose to increased risk of hypoglycemia, however; some inconsistency relates to the risk of the ACE genotype. We investigated the association between S-ACE level at diagnosis and ACE genotype to long-term risk of severe hypoglycemia in more than 1000 children and adolescents with type 1 diabetes being part of the Danish Registry of Childhood diabetes over a 10-yr period.

RESEARCH DESIGN AND METHODS

The Registry provided annual registration of clinical data, e.g., HbA1c, blood glucose monitoring, insulin type and dosage and acute diabetic complications (hypoglycemia and DKA). A BioBank coupled to the Registry comprised serum for measuring S-ACE levels and DNA for ACE genotyping.

RESULTS

A total of 1037 individuals were included, aged 9.97 yr (SD 3.84). A total of 622 severe hypoglycemic episodes were observed in 270 individuals. Associations to increased risk of hypoglycemia generated from a negative binominal model were long diabetes duration (p < 0.0001) and high S-ACE level (p = 0.0497) when adjusted for ACE genotype. In the stratified analysis, S-ACE and insulin dosage were associated with hypoglycemia in girls (p = 0.026 and 0.028, respectively). An association of S-ACE level to ACE genotype was identified; however, no difference in the frequency of hypoglycemia, diabetes duration or HbA1c was demonstrated between ACE genotypes.

CONCLUSION

This large nationwide cohort has identified an increased risk for hypoglycemia associated with higher S-ACE level, however only in girls. A strong association was found between ACE genotype and S-ACE levels, but ACE genotype was not related to risk of hypoglycemia.

Angiotensin-converting enzyme and angiotensin II receptor subtype 2 genotypes in type 1 diabetes and severe hypoglycaemia requiring emergency treatment: a case cohort study

AIMS

In type 1 diabetes, individual susceptibility to severe hypoglycaemia is likely to be influenced by genetic factors. We have previously reported an association of the deletion (D-) allele of the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism and the A-allele of the angiotensin II receptor subtype 2 (AT2R) 1675 G>A polymorphism with risk of severe hypoglycaemia in such patients. The aim of this study was to test the hypothesis that these alleles are more frequent in patients suffering from the most severe episodes of hypoglycaemia requiring medical emergency treatment.

METHODS

The case cohort study consisted of 108 cases of type 1 diabetic patients with severe hypoglycaemia requiring medical emergency treatment during a 1-year period and 262 consecutive controls without such events. ACE I/D and AT2R 1675G>A genotype distributions were compared between cases and controls.

RESULTS

The proportion of D-allele carriers was higher amongst cases than controls (83 vs. 73%; P=0.032). In contrast, AT2R genotype distribution was similar in cases and controls. In a multiple regression analysis, D-allele carriage remained a significant risk factor for being a case [odds ratio: 1.9 (1.0-3.6)] together with male sex, impaired symptomatic awareness of hypoglycaemia and presence of nephropathy.

CONCLUSION

The D-allele of the ACE gene is associated with severe hypoglycaemia requiring emergency treatment in type 1 diabetic patients with preserved spontaneous ACE activity. This supports the association between high ACE activity and occurrence of severe hypoglycaemia.

Serum angiotensin-converting enzyme and frequency of severe hypoglycaemia in Type 1 diabetes: does a relationship exist?

AIMS

An association has been described between elevated serum angiotensin-converting enzyme (ACE) and an increased risk of severe hypoglycaemia (SH). To ascertain whether this reported association could be replicated in a different country, it was re-examined in 300 individuals with Type 1 diabetes.

METHODS

People with Type 1 diabetes, none of whom was taking renin-angiotensin system blocking drugs, were recruited. Participants recorded the frequency with which they had experienced SH. Glycated haemoglobin (HbA(1c)) and serum ACE were measured. The difference in the incidence of SH between different quartiles of ACE activity and the relationship between serum ACE and SH were examined using non-parametric statistical tests and a negative binomial model.

RESULTS

Data were obtained from 300 patients [158 male; HbA(1c) median (range) 8.2% (5.2-12.8%), median age 36 years (16-88); duration of diabetes 14.5 years (2-49)]. The incidence of SH was 0.93 episodes per patient year. The mean incidence of SH in the top and bottom quartiles of ACE activity was 0.5 and 1.7 episodes per patient year, respectively, but this difference was not statistically significant (P = 0.075). Spearman's test showed a very weak, although statistically significant, association between serum ACE level and SH incidence (r = 0.115, P = 0.047). The binomial model also showed a statistically significant (P = 0.002), but clinically weak, relationship between serum ACE and SH.

CONCLUSIONS

The present survey showed a weak relationship between serum ACE and the frequency of SH, the clinical relevance of which is unclear. This limits the proposed role for serum ACE as an index of risk for SH.