Non-cancer Causes Of Death Research Articles

Longevity is the most appropriate measure of health effects of radiation.

It has been known for about a century that large doses of radiation, which are now uncommon, increase the risk of cancer. In this communication, I present evidence that moderate-dose-rate radiation significantly increases longevity without an increase in cancer. I suggest that longevity is a more appropriate measure of health effects of radiation than is cancer mortality. A double-blind study of humans would be necessary, however, to determine the health effects of low-dose radiation (1). I believe that the 100-year (1897–1997) study of British radiologists is the most important study of health effects of moderate-dose-rate radiation ever published (2). In the study, the death rates of British radiologists from cancer, noncancer, and all causes were compared with those of all male nonradiologist physicians in England and Wales, hereafter referred to as the controls. Findings of the study showed that radiologists who joined a radiologic society between 1897 and 1920 had 75% greater cancer mortality than did the controls. There is no doubt that the significant cancer increase (P .001) was caused by their high radiation doses. The increased radiation appeared to have had an important beneficial effect on deaths from noncancer that was not noticed at the time. The 1897–1920 radiologists’ death rate from noncancer was 14% lower (P .05) than that of the controls. This reduced noncancer death rate canceled out the increased death rate from cancer. The radiologists’ deaths from all causes were slightly fewer than those of the controls. Thus, the overall longevity of the earliest radiologists’ as a group was not reduced despite their high radiation doses and despite their increased cancer. The abstract of the article (2) concludes that “[t]here was no evidence of an effect of radiation on diseases other than cancer even in the earliest radiologists, despite the fact that doses of the size received by them have been associated with more than a doubling in the death rate among the survivors of the Japanese atomic bombings.” I believe the authors overlooked the fact that the significant decrease (P .05) in radiologists’ deaths from noncancer can only be explained as a reduction of deaths from diseases other than cancer compared with that of the controls. The article (2) concludes with the true statement that “[f]or non-cancer causes of death there was not evidence of an increased risk in any group, even among those registering before 1921.” However, it does not mention the 14% decrease (P .05) in deaths from noncancer before 1921 and the 14% decrease (P .001) in deaths from noncancer for the 100 years, as was pointed out in my letter to the editor (3). A similar study of U.S. radiologists suggests that their health was better than that of other medical specialists after 1940 (4). Present radiation protection limits for workers and the public are based largely on cancer deaths of atomic bomb survivors. The significant increase in deaths from noncancer of the atomic bomb survivors who received high doses of radiation compared with the significant reduction in deaths from noncancer of the radiologists, who received higher doses but over a longer period of time, indicates that atomic bomb survivor data are not appropriate for predicting longevity for radiation workers or the public. The longevity data obtained from the study of the British radiologists indicate that the dose limit of 0.2 R/day (about 50 rad/year) recommended for radiation workers by the International Commission for Radiological Health in 1934 did not need to be lowered. The very high doses of radiation received by the earliest radiologists did not reduce their overall longevity as a group. British radiologists who joined a society after 1920 also had a 14% lower (P .001) death rate from noncancer and an 8% lower (P .01) death rate from all causes than did the controls. British radiologists who joined a radiologic society after 1920 never had a statistically significant excess of cancer mortality compared with that of the controls. This contradicts the present dogma of a linear increase of cancer with dose. The abrupt decrease in cancer Opinion

Ageism in the management of lung cancer.

age-related differences in the treatment of lung cancer patients have been reported in the past, but most previous studies have not recorded case-mix factors, nor have they studied the impact of such ageism on survival. a questionnaire-based study of diagnostic and case-mix factors was carried out across 48 hospital Trusts in the UK between 1997 and 1998. We identified 1,652 patients and followed through with regard to their treatment and survival for 6 months after diagnosis. the median age of the population was 69 years, and for this analysis, was divided into three age groups: under 65 years, 65-74 and 75 years and over. There were significant inverse correlations between age and histological diagnosis, any active treatment and survival, even when corrected for case-mix factors and non-cancer causes of death. For example, the surgical resection rate in patients with confirmed non-small cell lung cancer with good performance status, no chronic obstructive pulmonary disease and limited disease was 37% in the younger patients compared with 15% in those 75 and over. The overall mortality rates at 6 months ranged from 42% in patients under 65 to 58% in the over 75s. this national study of lung cancer care in the UK has shown large age-related differences in management and survival in patients with lung cancer, largely independent of case-mix factors. The reasons for this are complex but such under-treatment in the elderly may be one factor underlying the poor outcomes in lung cancer patients in the UK.

Pathogenic effects of low dose irradiation: dose–effect relationships

There is no evidence of pathogenic effects in human groups exposed to less than 100 mSv at low dose-rate. The attributed effects are therefore the result of extrapolations from higher doses. The validity of such extrapolations is discussed from the point of view of epidemiology as well as cellular and molecular biology. The Chernobyl accident resulted in large excess of thyroid cancers in children; it also raised the point that some actual sanitary effects among distressed populations might be a direct consequence of low doses. Studies under the control of UN have not confirmed this point identifying no dose–effect relationship and “ severe socio-economic and psychological pressures… poverty, poor diet and living conditions, and lifestyle factors” as the main cause for depressed health. Some hypothesis are considered for explaining the dose-dependence and high prevalence of non-cancer causes of death among human groups exposed to more than 300 mSv. To cite this article: R. Masse, C. R. Physique 3 (2002) 1049–1058.

100 years of observation on British radiologists: mortality from cancer and other causes 1897–1997

Radiologists and radiotherapists were one of the earliest occupational groups to be exposed to ionizing radiation. Their patterns of mortality provide information on the long-term effects of fractionated external radiation exposure. British radiologists who registered with a radiological society between 1897 and 1979 have now been followed-up until 1 January 1997, and the mortality experience examined among those who registered with a society after 1920, when the first radiological protection recommendations were published. The observed number of cancer deaths in those who registered after 1920 was similar to that expected from death rates for all medical practitioners combined (SMR=1.04; 95% CI 0.89-1.21). However, there was evidence of an increasing trend in risk of cancer mortality with time since first registration with a radiological society (p=0.002), such that in those registered for more than 40 years there was a 41% excess risk of cancer mortality (SMR=1.41; 95% CI 1.03-1.90). This is probably a long-term effect of radiation exposure in those who first registered during 1921-1935 and 1936-1954. There was no evidence of an increase in cancer mortality among radiologists who first registered after 1954, in whom radiation exposures are likely to have been lower. Non-cancer causes of death were also examined in more detail than has been reported previously. There was no evidence of an effect of radiation on diseases other than cancer even in the earliest radiologists, despite the fact that doses of the size received by them have been associated with more than a doubling in the death rate among the survivors of the Japanese atomic bombings.

Registration of cancer mortality data in a developing area: Chennai (Madras, India) experience.

This study was carried out to evolve a method to improve the registration of cancer mortality data in Chennai (Madras, India). Data on cancer deaths have been collected from the Vital Statistics Department (VSD) by a population-based cancer registry (PBCR) in Chennai only since 1982. The low mortality-to-incidence ratio during 1982-84 suggested under-registration of mortality data. Since 1985, the PBCR has taken special effort to ascertain the vital status of cancer cases by sending reply-paid postcards and/or making house visits. The data on all deaths occurring in Chennai, irrespective of stated cause of death in the death certificate, have been collected from the VSD since 1992. Deaths that occurred in Chennai and obtained by sending reply-paid postcards and/or making house visits were registered in VSD as non-cancer causes of death; hence, these data were not collected from VSD. The sensitivity and positive predictive values of death certificates on cancer diagnosis based on 1992 and 1993 mortality data were 57 percent and 99.5 percent, respectively. Since the accuracy of death certificate information on cancer diagnosis is relatively low in a developing country such as in India, collecting data on all deaths will improve the mortality data registration in PBCRs.

Report of the Conference on Low Blood Cholesterol: Mortality Associations.

A National Heart, Lung, and Blood Institute (NHLBI) Conference was held October 9-10, 1990, to review and discuss existing data on U-shaped relations found between mortality rates and blood total cholesterol levels (TC) in some but not other studies. Presentations were given from 19 cohort studies from the United States, Europe, Israel, and Japan. A representative of each study presented its findings and also submitted tables of proportional hazards regression coefficients for entry TC levels in regard to death, and these were incorporated into a formal statistical overview adjusted for age, diastolic blood pressure, cigarette smoking, body mass index, and alcohol intake, as available. The U-shape for total mortality in men and the flat relation in women resulted largely from a positive relation of TC with coronary heart disease death and an inverse relation with deaths caused by some cancers (e.g., lung but not colon), respiratory disease, digestive disease, trauma, and residual deaths. Risk for combined noncardiovascular, noncancer causes of death decreased steadily across the range of TC. The conference considered possible explanations for the statistical associations found between low TC levels or active TC lowering and certain causes of death. One is that TC is lowered by some disease conditions themselves, such as wasting in chronic pulmonary disease or reduced production and secretion of cholesterol-bearing lipoproteins with liver disease. In this sort of situation, the TC:mortality association found in observational studies may be due to preexisting disease. This was addressed by excluding early deaths from the analysis, which did not change the results. The conference considered as well the biological function of cholesterol, which, if seriously deranged, might hypothetically cause a wide variety of diseases and dysfunction. The conference also considered the biological functions that might provide plausible mechanisms for the associations found. Definitive interpretation of the associations observed was not possible, although most participants considered it likely that many of the statistical associations of low or lowered TC level are explainable by confounding in one form or another. The conference focused on the apparent existence and nature of these associations and on the need to understand their source rather than on any pertinence of the findings for public health policy. Further research is recommended to explain the observed associations of low TC levels (and TC lowering) with certain noncardiovascular diseases. This includes studies of the time course of TC change in disease, the relation of TC to morbidity, further studies of possible epidemiological confounding, monitoring of population trends in TC and mortality, further studies of the relations in women, auditing of noncardiovascular events in trials, studies of cell membrane, genetic and molecular links to cholesterol metabolism, TC level and disease, studies of disease manifestations in specific lipid disorders, and further study of the proposed causal mechanisms linking low TC and hemorrhagic stroke.

Cancer Mortality, Aging, and Patterns of Comorbidity in the United States: 1968 to 1986

Cancer is often reported as contributing to the risk of noncancer causes of death. The age variation of these reports was studied using U.S. data on all causes of death listed on death certificates for 1968 to 1986. The occurrence of cancer as a nonunderlying cause of death increased with age and was higher for treatable and slowly growing tumor types. These patterns persisted even if the cancer manifested changes in occurrence. Nonunderlying occurrences were highest in the 85 to 94 age group and were correlated with cancer survival. This suggests increased importance of cancer as a cause of death and a comorbid condition among oldest-old persons. The high rate of occurrence as an associated cause of death suggests that if life expectancy increases due to declines in circulatory and other chronic disease mortality, cancer could become the preeminent cause of death in the United States.

Population based mortality surveillance in carbon products manufacturing plants.

The utility of a population based, corporate wide mortality surveillance system was evaluated after a 10 year observation period of one of the company's divisions. The subject population, 2219 white male, long term employees from Union Carbide Corporation's carbon based electrode and specialty products operations, was followed up for mortality from 1974 to 1983. External comparisons with the United States male population were supplemented with internal comparisons among subgroups of the study population, defined by broad job categories and time related variables, adjusting for important correlates of the healthy worker effect. Significant deficits of deaths were observed for all causes and the major non-cancer causes of death. The numbers of deaths due to malignant neoplasms and respiratory cancer were less than, but not statistically different from, expected. There was a non-significant excess of deaths from lymphopoietic cancer, occurring predominantly among salaried employees. When specific locations were examined, operations with potential exposure to coal tar products exhibited a mortality pattern similar to that of the total cohort. The risk for lung cancer was significantly raised (five observed, 1.4 expected) in one small, but older, location which did not involve coal tar products during the period of employment of these individuals, but which historically used asbestos materials for several unique applications. Although these findings are limited by small numbers and a short observation period, the population based surveillance strategy has provided valuable information regarding the mortality experience of the population, directions for future research, and the allocation of epidemiological resources.