Hypoglycaemia: Hypoglycaemia was usually symptomatic

Clinical bottom line (level 1b)

  1. In patients with insulin-dependent diabetes mellitus (IDDM) symptoms of hypoglycaemia were rarely absent with blood sugars <3mmol/L (LR+8.3) (LR-0.56)
  2. In IDDM patients with symptoms of hypoglycaemia, about a third of cases were biochemically confirmed
Pramming et al: J Internal Medicine 1990; 228: 641-646
Expires February 2003

The study

Setting: out-patients at a Danish University Hospital

90 patients (aged mean 33.4y (range 17-59), ?% male) randomly selected IDDM out-pts

Independent unblinded reference standard, applied in all patients from a ?consecutive appropriate spectrum.
Reference standard:
  • capillary measurement of blood glucose <3mmol/L
Diagnostic test: symptoms of hypoglycaemia, either at a pre-determined test-time or any other time
  • Multiple tests were taken for 7 days; aiming to detect asymptomatic hypoglycaemia
  • 24 patients did not complete tests fully and were excluded

The evidence

pre-test probability of hypoglycaemic episodes (regular and symptom-driven measurements): 6%, (95% CI: 5.0% to 6.9%)
pre-test probability of hypoglycaemia (symptom-driven tests only): 29%, (95% CI: 22% to 35%)

diagnostic test hypoglycaemia normoglycaemic LR+
(95% CI)		 post-test probability LR-
(95% CI)		 post-test probability
symptoms of hypoglycaemia 69 131 8.3
(6.5 to 10.5) 		35% 0.56
(0.48 to 0.66) 		3%
total 149 2346

Comments

  1. Good attempt at including in the study episodes of asymptomatic hypoglycaemia

Citation

  1. Pramming S, Thorsteinsson B, Bendtson I: The relationship between symptomatic and biochemical hypoglycaemia in insulin-dependant diabetic patients.. J Internal Medicine 1990; 228: 641-646
Contributor: MJ Taylor and Bob Phillips, February 1998
Reviewer: .

Clinical Question.
Patient In diabetic patients with suspected hypoglycaemia
Intervention or Exposure the symptoms of hypoglycaemia
Outcome reflect biochemical hypoglycaemia