Effects of hypoglycaemia on working memory and regional cerebral blood flow in type 1 diabetes: a randomised, crossover trial.
Diabetologia
; 61(3): 551-561, 2018 03.
Article
em En
| MEDLINE
| ID: mdl-29188338
ABSTRACT
AIMS/HYPOTHESIS:
The aim of this randomised, crossover trial was to compare cognitive functioning and associated brain activation patterns during hypoglycaemia (plasma glucose [PG] just below 3.1 mmol/l) and euglycaemia in individuals with type 1 diabetes mellitus.METHODS:
In this patient-blinded, crossover study, 26 participants with type 1 diabetes mellitus attended two randomised experimental visits one hypoglycaemic clamp (PG 2.8 ± 0.2 mmol/l, approximate duration 55 min) and one euglycaemic clamp (PG 5.5 mmol/l ± 10%). PG levels were maintained by hyperinsulinaemic glucose clamping. Cognitive functioning was assessed during hypoglycaemia and euglycaemia conditions using a modified version of the digit symbol substitution test (mDSST) and control DSST (cDSST). Simultaneously, regional cerebral blood flow (rCBF) was measured in pre-specified brain regions by six H215O-positron emission tomographies (PET) per session.RESULTS:
Working memory was impaired during hypoglycaemia as indicated by a statistically significantly lower mDSST score (estimated treatment difference [ETD] -0.63 [95% CI -1.13, -0.14], p = 0.014) and a statistically significantly longer response time (ETD 2.86 s [7%] [95% CI 0.67, 5.05], p = 0.013) compared with euglycaemia. During hypoglycaemia, mDSST task performance was associated with increased activity in the frontal lobe regions, superior parietal lobe and thalamus, and decreased activity in the temporal lobe regions (p < 0.05). Working memory activation (mDSST - cDSST) statistically significantly increased blood flow in the striatum during hypoglycaemia (ETD 0.0374% [95% CI 0.0157, 0.0590], p = 0.002). CONCLUSIONS/INTERPRETATION:
During hypoglycaemia (mean PG 2.9 mmol/l), working memory performance was impaired. Altered performance was associated with significantly increased blood flow in the striatum, a part of the basal ganglia implicated in regulating motor functions, memory, language and emotion. TRIAL REGISTRATION NCT01789593, clinicaltrials.govFUNDING:
This study was funded by Novo Nordisk.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Circulação Cerebrovascular
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Diabetes Mellitus Tipo 1
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Hipoglicemia
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Memória de Curto Prazo
Tipo de estudo:
Clinical_trials
Limite:
Adult
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Female
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Humans
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Male
/
Middle aged
Idioma:
En
Revista:
Diabetologia
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Dinamarca