Death etiology

Obviously, one looks for causes. That declines in one or another species have natural factor etiologies is unequivocal. The demise of American elms and of the chestnut were due to natural factors. Insect infestations, bacterial and fungal diseases, hurricanes, floods, freezes, droughts and many other stresses can cause extensive tree death (5). But in such declines typically only a single species is affected or climatic events caused decline in a delimited area. In almost all declines caused by natural events, the causal factors can be identified we know their precise etiologies. Natural events are always part of the natural environment and must be factored in when evaluating forest declines (Table I). 

Approximately 400,000 people die of sudden cardiac death annually in the United States. While some of these deaths occur as a result of asystole, the majority occur as a result of primary VF or VT that degenerates into VF. Etiologies of VF are presented in Table 6-10 and are similar to those of VT. 

PD affects approximately one million Americans (1% of people over 60 years of age). The average age of onset is 60 years of age, and PD is fairly uncommon in those under age 40. The etiology of PD is unknown, but genetic predisposition, environmental factors, or combinations of these have been proposed to explain why nerve cells in the substantia nigra deteriorate. About 15% of patients with PD have a first-degree relative with the disease. The pathogenesis of cell death (neuron degeneration) may be due to oxidative stress, mitochondrial... 

Khera, K.S. (1985). Maternal toxicity A possible etiological factor in embryo-fetal deaths and fetal malformations of rodent-rabbit species. 

Alterations in the ubiquitin-proteasome pathway have been connected to several neurodegenerative diseases (Table 9). In some instances, mutations in specific genes have been linked to the etiology of the disease. Although the perturbations in ubiquitin-proteasome-mediated proteolysis lead to pleiotropic effects on neurons including cell death or degeneration, one of the early effects is believed to be synaptic malfunction. 

In the U.S., fish and shellfish caused at least one in six food poisoning outbreaks with known etiologies, and 15% of the deaths associated with these outbreaks during 1988 to 1992. This is a marked increase over the preceding decade, when seafood consumption was associated with 10% of foodborne disease outbreaks that had identified etiologies (Ahmed, 1992 Centers for Disease Control and Prevention, 1996 Lipp and Rose, 1997). 

The reported number of cases of bacterial foodborne poisonings (BFBP) and the deaths they cause worldwide is enormous, both in developing and industrialized countries. In the U.S. alone, each year 76 million foodborne illnesses are reported and 325,000 patients are hospitalized, of which 5000 die. The etiological agent is identified only in 18% of cases, the rest remain undiagnosed or misdiagnosed (Mead et al., 1999). 

The results of MADIT II were met with some skepticism, but later confirmed by the recent Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT) [24]. This study evaluated the benefit of ICD therapy versus amiodarone or placebo as primary prevention in over 2,500 patients with stable NYHA class II or III heart failure and EF < 35%, without the requirement for NSVT or EPS. Patients with both ischemic and nonischemic etiologies for cardiomyopathy were included. Over a follow-up of 4 years, there was no benefit of amiodarone over placebo for overall mortality, but ICD therapy resulted in a significant 23% reduction in overall mortality [p = 0.007] (Fig. 3.5). The benefit of ICD therapy was comparable for ischemic and nonischemic cardiomyopathy. 

Bove FJ, Fulcomer MC, Klotz JB, et al. 1992a. Population-based surveillance and etiological research of adverse reproductive outcomes and toxic wastes. Report on Phase IV-A Public drinking water contamination and birthweight, fetal deaths, and birth defects. A cross-sectional study. New Jersey Department of Health. 

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