Hypoglycaemia Unawareness in Long-Standing Type 1 Diabetes: A Narrative Review of Restoring Awareness
DOI:
https://doi.org/10.5281/zenodo.22238757Keywords:
Type 1 diabetes, Impaired awareness of hypoglycaemia, Gold score, Severe hypoglycaemia, Continuous glucose monitoringAbstract
Losing the warning symptoms of hypoglycaemia is among the more dangerous developments in long-standing type 1 diabetes, and
it is identified in clinic by questionnaire. How many people have it depends heavily on which questionnaire is used: applied to the
same cohort, the Gold, Clarke and Pedersen-Bjergaard instruments classified 33.3, 43.7 and 77.0 per cent respectively as having
impaired awareness. All three identify a group at real risk, with reported increases in severe hypoglycaemia of six-fold, 4.63-fold
and 5.83-fold. The difficulty is what they miss. In a contemporary cohort of 782 adults, 49 per cent of those who reported a severe
episode had a Gold score below the impairment threshold, and the score achieved a sensitivity of 51 per cent for classifying risk.
Impaired awareness is also associated with socioeconomic deprivation and with a positive depression screen, so it is not a purely
physiological finding. This review sets out the physiology, the measurement problem, what technology has changed, and why a
reassuring questionnaire should not end the conversation.
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