Dead-in-bed syndrome in diabetes mellitus.

SIR—Ragnar Hanas (Aug 16, p 492) suggests that the dead-in-bed syndrome among patients with insulin-dependent diabetes mellitus (IDDM) may be due to an accidental overdose of shortacting insulin before retiring to bed. Though Hanas’ entry was published as a research letter, it did not, in fact, include any research findings to support this hypothesis. Hanas seems to suggest that the mistake occurs in patients on four times daily insulin regimens (shortacting insulin before meals and intermediate-acting insulin at bedtime), but only a few cases reported as dead in bed are on such regimens. For example, in the original report of the syndrome by Tattersall and Gill, four (18%) of the 22 cases were on four daily injections of insulin, 16 were on twice daily insulin, and two on once daily insulin. Furthermore, nocturnal hypoglycaemia is common in insulindependent diabetic patients whereas the dead-in-bed syndrome is rare. Hypoglycaemia could be important in the pathogenesis of sudden nocturnal death in IDDM, and accidental insulin overdose may contribute in some cases but certainly not all. It is noteworthy that patients with this syndrome are found in undisturbed beds with no signs of sweating, struggle, or seizure. This finding implies that other mechanisms alongside nocturnal hypoglycaemia are involved in the pathogenesis of sudden death in these cases—for example, accompanying cardiac arrhythmias.