Erythrocyte choline concentrations and cluster headache.

Erythrocyte choline concentrations were measured in patients with cluster headache and age related control subjects. Concentrations were significantly reduced in the patients with headache both during a cluster period and between clusters, being 58% and 55% of the control value, respectively. After two weeks' treatment with lithium, choline concentrations in the patients with cluster headache increased to 78 times the control value (mean 369.2 mumol/l (3840 micrograms/100 ml) compared with 4.7 mumol/l (49 micrograms/100 ml]. The presence of depressed erythrocyte choline concentrations during and between cluster attacks indicates that this may be a predisposing condition which results in a cluster attack only when associated with a trigger factor.