LONGITUDINAL GOMPERTZIAN ANALYSIS OF PRIMARY MALIGNANT BRAIN-TUMOR MORTALITY IN THE UNITED-STATES 1962-1987 - RISING MORTALITY IN THE ELDERLY IS THE NATURAL CONSEQUENCE OF COMPETITIVE DETERMINISTIC DYNAMICS

Age-adjusted mortality rates for primary malignant brain tumors (PMBT) in the United States from 1962 to 1987 were subjected to longitudinal Gompertzian analysis. Age-adjusted PMBT mortality rate distributions between age 25 and 65 years were determined by a variable environmental factor and a common intersect point. The environmental factor declined (improved) 1.58-fold for men and 2.34-fold for women in 1987 as compared to 1962. The age at the common intersect point was 68.4 years for men and 64.1 years for women. Between 1962 and 1987, non-age-standardized annual crude PMBT mortality rates increased 14.5%, for men and 37.8%, for women. However, PMBT mortality rates at age 77.5 years rose 25% for men and 409%, for women between 1962 and 1987. Longitudinal Gompertzian analysis of PMBT mortality data suggests that rapidly rising PMBT mortality rates in the elderly are the natural consequence of competitive deterministic mortality dynamics and should not be attributed to environmental factors, past or present, that are directly contributing to PMBT mortality. Furthermore, longitudinal Gompertzian analysis demonstrates that PMBT mortality should not be studied in isolation, but rather should be examined in relation to other causes of death. When viewed from this perspective, the basis for the dramatic rise in PMBT mortality in the elderly becomes quite evident.