[Analysis of the cohort effect on the trend in mortality from motor neuron disease in Spain, 19551-1002].
BACKGROUND
An increase in the mortality due to motor neuron disease (MND) has been reported in Spain over the past 30-40 years. It has been suggested that this increase is due to the cohort effect, but his hypothesis has not been proven.


METHODS
The motor neuron disease (MND) mortality statistics by age and by gender were furnished from the Spanish National Institute of Statistics. The mortality specifically by age and the adjusted age-related rates were calculated. By Poisson regression, the cohort effect of birth on the mortality by ages has been analyzed, the cohort effect also having been analyzed by graphic methods.


RESULTS
The mortality adjusted by age was declining up until 1969, as of which time it has been on the rise. Each five-year birth cohort increases the risk of dying from MND by 8.5%.


CONCLUSIONS
The increase in the mortality due to MND in Spain is the result of a cohort effect.
Llorca Díaz
J
J
Cátedra de Medicina Preventiva y Salud Pública, Facultad de Medicina, Universidad de Cantabria. llorcaj@medi.unican.es
Prieto Salceda
M D
MD
Delgado-Rodríguez
M
M
D000328:Adult; D015988:Cohort Effect; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016472:Motor Neuron Disease / Q000453:epidemiology / Q000401:mortality*; D013030:Spain / Q000453:epidemiology
Análisis del effecto de cohorte en la evolución de la mortalidad por enfermedad de la motoneurona en España, 1951-1992.