To the Editor.
—We write concerning the epidemic of neuropathy that has been affecting Cubans since 1991. As of June 18, 1993, more than 45000 cases had been reported, with 86.6% of the patients between the ages of 25 and 64 years. The principal clinical forms are optic neuropathy and myeloneuropathy. This condition has been called epidemic neuropathy.1We believe that Leber's disease can be used as a theoretical model to explain greater susceptibility of certain persons to epidemic neuropathy. It is possible that the risk of developing epidemic neuropathy is higher in genetically susceptible persons and those with Leber's disease than among those lacking this genotype.Nikoskelainen et al2 observed that the frequency of preexcitation syndromes in patients with Leber's disease and their families was unusually high. The fact that this disease is mitochondrial would explain the electrocardiographic changes in the patients.3With this background information