ABSTRACT
AIMS: To examine whether severe hypoglycaemia and impaired hypoglycaemic awareness, a principal predictor of severe hypoglycaemia, are associated with all-cause mortality or cardiovascular mortality in Type 1 diabetes mellitus. METHODS: Mortality was recorded in two cohorts, one in Denmark (n = 269, follow-up 12 years) and one in the Netherlands (n = 482, follow-up 6.5 years). In both cohorts, awareness class was characterized and numbers of episodes of severe hypoglycaemia either during lifetime (Danish cohort) or during the preceding year (Dutch cohort) were recorded. In addition, episodes of severe hypoglycaemia were prospectively recorded every month for 1 year in the Danish cohort. Follow-up data regarding mortality were obtained through medical reports and registries (Danish cohort). RESULTS: All-cause mortality was 14% (n = 39) in the Danish and 4% (n = 20) in the Dutch cohort. In either cohort, neither presence of episodes with severe hypoglycaemia nor impaired hypoglycaemia awareness were associated with increased mortality in age-truncated Cox proportional hazard regression models. Variables associated with increased risk of all-cause mortality in both cohorts were evidence of macrovascular disease and reduced kidney function. CONCLUSIONS: Severe hypoglycaemia and hypoglycaemia unawareness are not associated with increased risk of all-cause or cardiovascular mortality in people with Type 1 diabetes mellitus.
Subject(s)
Cardiovascular Diseases/epidemiology , Diabetes Mellitus, Type 1/therapy , Diabetic Angiopathies/epidemiology , Diabetic Cardiomyopathies/epidemiology , Diabetic Nephropathies/epidemiology , Diagnostic Self Evaluation , Hypoglycemia/diagnosis , Alcohol Drinking/adverse effects , Cardiovascular Diseases/complications , Cardiovascular Diseases/mortality , Cohort Studies , Denmark/epidemiology , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/complications , Diabetic Angiopathies/complications , Diabetic Angiopathies/mortality , Diabetic Cardiomyopathies/complications , Diabetic Cardiomyopathies/mortality , Diabetic Nephropathies/complications , Diabetic Nephropathies/mortality , Female , Follow-Up Studies , Humans , Hypoglycemia/mortality , Hypoglycemia/physiopathology , Hypoglycemia/prevention & control , Male , Middle Aged , Mortality , Netherlands/epidemiology , Outpatient Clinics, Hospital , Prevalence , Prospective Studies , Registries , Risk Factors , Severity of Illness Index , Survival AnalysisABSTRACT
Hypoglycemic events have been proven to be associated with measurable EEG changes. Several works in the literature have evaluated these changes by considering approaches at the single EEG channel level, but multivariate analyses have been scarcely investigated in Type 1 diabetes (T1D) subjects. The aim of the present work is to assess if and how hypoglycemia affects EEG coherence in a subset of EEG channels acquired in a hospital setting where eye- and muscle activation-induced artifacts are virtually absent. In particular, EEG multichannel data, acquired in 19 T1D hospitalized subjects undertaken to an insulin-induced hypoglycemia experiment, are considered. Computation of Partial Directed Coherence (PDC) through multivariate autoregressive models of P3-A1A2, P4-A1A2, C3-A1A2 and C4-A1A2 EEG channels shows that a decrease in the value of coherence, most likely related to the progressive loss of cognitive function and altered cerebral activity, occurs when passing from eu- to hypoglycemia, in both theta ([4, 8] Hz) and alpha ([8, 13] Hz) bands.
