Trends in mortality from sporadic Creutzfeldt-Jakob disease in France 1992-7.

This study examined trends in mortality from sporadic Creutzfeldt-Jakob disease in France for 1992-7 by age, genotype at the codon 129 of the prion protein gene, and geographical area. Case ascertainment was based on notifications by neurologists, neuropathologists, and laboratories; 324 deaths from definite or probable Creutzfeldt-Jakob disease were registered during the study period. The yearly number of deaths increased significantly between 1992 and 1997. The rise was higher for older age groups. It was also higher in those who were homozygous for valine compared with other genotypes. Eighteen departments (geographical administrative areas) out of 95 showed a significant increase in the number of deaths from sporadic Creutzfeldt-Jakob disease. Intensive epidemiological surveillance is a likely explanation for the apparent increase in the number of sporadic cases of Creutzfeldt-Jakob disease over the 1992-7 period, particularly in older age groups and in departments with low mortality rate at the beginning of the study period. Intensive surveillance may also have led to a better identification of atypical valine homozygous cases.