[Mortality due to multiple sclerosis in Spain, 1951-1992]

FOUNDATIONS: In this work, multiple sclerosis mortality trend in Spain from 1951 to 1992 is displayed. The purpose is to identify the pattern of age-adjusted mortality evolution and to measure the effect of environmental factors.

Multiple sclerosis mortality is standardized by age using the world standard population. In each year from 1951 to 1992, age-specific mortality rates are transversely fitted to the Gompertz law. The Longitudinal Gompertzian analysis is applied to the obtained coefficients to quantify the effects of competing risks and environmental factors.

Multiple sclerosis age-adjusted mortality increased from 1951 to 1968; a step-down is produced in 1969 (coinciding with change from 7th to 8th revision of the International Classification of Diseases) and a stability from 1970 on. Multiple sclerosis in Spain is a Gompertzian disease. Adjusting mortality for R0 (which in the Gompertz function represents the addition of the environmental factors acting in a point near the beginning of the life and the competing risks of death) the result was almost constant throughout the whole analyzed period.

It is suggested that multiple sclerosis mortality trend in Spain is due to changes in some environmental factor acting early and in a point; on the other hand, diet or other environmental factors acting for long time or genetic factors have and little or no influence in this trend.