Glycemic variability and all-cause mortality in a large prospective southern European cohort of patients with differences in glycemic status

Effect of glucose variability on the mortality of adults aged 75 years and over during the first year of the COVID-19 pandemic

BACKGROUND

To our knowledge, only one study has examined the association between glucose variability (GV) and mortality in the elderly population with diabetes. GV was assessed by HbA1c, and a J-shaped curve was observed in the relationship between HbA1c thresholds and mortality. No study of GV was conducted during the COVID-19 pandemic and its lockdown. This study aims to evaluate whether GV is an independent predictor of all-cause mortality in patients aged 75 years or older with and without COVID-19 who were followed during the first year of the COVID-19 pandemic and its lockdown measures.

METHODS

This was a retrospective cohort study of 407,492 patients from the AGED-MADRID dataset aged 83.5 (SD 5.8) years; 63.2% were women, and 29.3% had diabetes. GV was measured by the coefficient of variation of fasting plasma glucose (CV-FPG) over 6 years of follow-up (2015-2020). The outcome measure was all-cause mortality in 2020. Four models of logistic regression were performed, from simple (age, sex) to fully adjusted, to assess the effect of CV-FPG on all-cause mortality.

RESULTS

During follow-up, 34,925 patients died (14,999 women and 19,926 men), with an all-cause mortality rate of 822.3 per 10,000 person-years (95% confidence interval (CI), 813.7 to 822.3) (739 per 10,000; 95% CI 728.7 to 739.0 in women and 967.1 per 10,000; 95% CI 951.7 to 967.2 in men). The highest quartile of CV-FPG was significantly more common in the deceased group (40.1% vs. 23.6%; p < 0.001). In the fully adjusted model including dementia (Alzheimer's disease) and basal FPG, the odds ratio for mortality ranged from 1.88 to 2.06 in patients with T2DM and from 2.30 to 2.61 in patients with normoglycaemia, according to different sensitivity analyses.

CONCLUSIONS

GV has clear implications for clinical practice, as its assessment as a risk prediction tool should be included in the routine follow-up of the elderly and in a comprehensive geriatric assessment. Electronic health records can incorporate tools that allow its calculation, and with this information, clinicians will have a broader view of the medium- and long-term prognosis of their patients.

The unique pathophysiological features of diabetes mellitus secondary to total pancreatectomy: proposal for a new classification distinct from diabetes of the exocrine pancreas

INTRODUCTION

Diabetes of the exocrine pancreas (DEP; a.k.a. pancreatic diabetes or pancreatogenic diabetes or type 3c diabetes mellitus or T3cDM) refers to different diabetes types resulting from disorders of the exocrine pancreas. DEP is characterized by the structural and functional loss of glucose-normalizing insulin secretion in the context of exocrine pancreatic dysfunction. Among these forms, new-onset diabetes mellitus secondary to total pancreatectomy (TP) has unique pathophysiological and clinical features, for which we propose a new nomenclature such as post-total pancreatectomy diabetes mellitus (PTPDM).

AREAS COVERED

TP results in the complete loss of pancreatic parenchyma, with subsequent absolute insulinopenia and lifelong need for exogenous insulin therapy. Patients with PTPDM also exhibit deficiency of glucagon, amylin and pancreatic polypeptide. These endocrine abnormalities, coupled with increased peripheral insulin sensitivity, deficiency of pancreatic enzymes and TP-related modifications of gastrointestinal anatomy, can lead to marked glucose variability and increased risk of iatrogenic (insulin-induced) severe hypoglycemic episodes ('brittle diabetes').

EXPERT OPINION

We believe that diabetes mellitus secondary to TP should not be included in the DEP spectrum in light of its peculiar pathophysiological and clinical features. Therefore, we propose a new classification for this entity, that would likely provide more accurate prognosis and treatment strategies.

Glycaemic variability and risk of adverse cardiovascular events in acute coronary syndrome

OBJECTIVE

The relationship between different glycaemic variability (GV) indexes and adverse cardiovascular outcomes is not well understood. This study aims to determine whether GV is related to the occurrence of adverse cardiovascular events in patients with acute coronary syndrome (ACS).

METHODS

PubMed, EMBASE, and Web of Science were comprehensively searched from the establishment of databases to 29 June 2022. The relationship between two important GV indexes, including the mean amplitude of glycemic excursion (MAGE) and standard deviation (SD), and the adverse cardiovascular events in ACS patients were evaluated, respectively.

RESULTS

A total of 11 studies with 3709 ACS patients were included. Pooled results showed that patients with higher GV had significantly increased risk of adverse cardiovascular events, including MAGE (relative risk [RR] = 1.76, 95% CI: 1.40 to 2.22, p < 0.001, I² = 25%) and SD (RR = 2.14, 95% CI: 1.73 to 2.66, p < 0.001, I² = 0%).

CONCLUSIONS

Increased GV is related to the poor prognosis in patients with ACS. Additionally, more well-designed studies comparing different indicators of GV with adverse cardiovascular events in ACS patients are still warranted.