Effects of dependency among causes of death for cause elimination life table strategies

A study is made of the effects of associated causes of death, and of dependency among causes of death, by observing the relative importance of one cause of death when another is eliminated under various competing risk models. Two disease pairs, cancer and infectious disease and stroke and ischemic heart disease, are selected for analysis because they represent different types of disease dependence. Crude probabilities of death for each disease are calculated for the U.S. white male population in 1969. Next, the effects of the complementary disease in a pair are hypothetically eliminated in one of three ways: (a) a standard competing risk adjustment for cause elimination when deaths are singly caused (Chiang, 1968), (b) lethal defect-pattern of failure computations for multiply caused death when no causal order is inferred (Manton et al., 1976), and (c) relative susceptibility, computations for multiply caused deaths when causes are ordered (Wong, 1977). The paper closes with a discussion of the relative merits of the three types of adjustments.     

Temporal trends in U. S. multiple cause of death mortality data: 1968 to 1977

An analysis is made of the mortality trends over the period 1968 to 1977 indicated by two types of cause-specific mortality data. The first type of data is “underlying cause” of death data—the data heretofore used in national vital statistics reports on cause-specific mortality. The second type of data is “multiple cause” data which contain a listing of all medical conditions recorded on the death certificate. A comparison of trends in the two types of data yields useful insights on mortality declines over the study period for two reasons. First, these declines were largely due to a reduction in the mortality rates of circulatory diseases. Second, the multiple cause data contain considerably more information than the underlying cause data on the role of circulatory diseases, and many other chronic diseases, in causing death. This additional information is especially useful in examining mortality patterns among the elderly, where the prevalence at death of chronic degenerative diseases is high.     

Recent trends in mortality in Australia—an analysis of the causes of death through the application of life table techniques

The paper examines the post-1971 reduction in Australian mortality in light of data on causes of death. Multiple-decrement life tables for eleven leading causes of death by sex are calculated and the incidence of each cause of death is presented in terms of the values of the life table functions. The study found that in the overall decline in mortality over the last 20 years significant changes occurred in the contribution of the various causes to total mortality. Among the three leading causes of death, heart disease, malignant neoplasms (cancer), and cerebrovascular disease (stroke), mortality rates due to neoplasms increased and those of the other two causes decreased. The sex-age-cause-specific incidence of mortality changed and the median age at death increased for all causes except for deaths due to motor-vehicle accidents for both sexes and suicide for males. The paper also deciphers the gains in the expectation of life at birth over various time periods and the sex-differentials in the expectation of life at birth at a point in time in terms of the contributions made by the various sex-age-cause-specific mortality rates.     

Mortality in England and Wales from 1848 to 1947

This is a survey of the changing causes of death in England and Wales during the past 100 years. Based on the published mortality statistics of the General Register Office the framework of the survey is a series of specially prepared tables of death rates by sex, age and cause of death for the periods 1848–72, 1901–10, 1921, 1931, 1939 and 1947. Adjustments were made wherever necessary to compensate for changes in medical nomenclature and in the statistical classification of disease.

After allowance has been made for the changing age structure of the population, the male death rate at all ages in 1947 was 42% of the rate in 1846–50, and the female rate 35 %. Maximum improvement was among girls aged 5–9 years, whose death rate in 1947 was 9% of the rate 100 years before.

In 1848–72 the group to which were allocated the largest proportion of the deaths at all ages were the infectious diseases with one-third of the total; and these were followed by the respiratory, nervous and digestive diseases. In 1947, on the other hand, diseases of the circulatory system came first with rather more than one-third of the total at all ages, and these were followed by cancer.

Changes in proportionate mortality rates from various causes have been examined at successive ages from infancy to old age. There was a decline in proportionate mortality from the infectious diseases other than tuberculosis, but increased mortality from tuberculosis in the younger age groups and from violence, circulatory diseases and cancer.

The trends of absolute mortality from the various causes were also studied. The reduction in total mortality was such that whereas there were half a million deaths of civilians registered in England and Wales in 1947, the total would have been over a million had the death rates of 1848–72 still prevailed.

The article concludes with a brief review of the factors responsible for the changes that have taken place.     

Recent trends in multiple-caused mortality 1968 to 1982: Age and cohort components

Declines in mortality at advanced ages have been observed recently in the United States. These declines have been related to a reduction in the risk of major circulatory diseases, such as stroke and heart disease. In this paper we examine the contribution of two additional major factors in those declines. The first is the effect of conditions associated with circulatory diseases. This effect can be examined by using multiple-cause mortality data in which all conditions reported by the physician on the death certificates are recorded. The second is the contribution of cohort mortality differentials to temporal changes. If major cohort differentials are identified, we may be able to determine if recent declines in mortality are likely to continue-and to what levels. Such insights would be useful both in improving projections of the size and age structure of the U.S. elderly population and its entitlement groups and in helping to identify future patterns of needs for preventive and other health services.     

Are mortality projections always more pessimistic when disaggregated by cause of death?

"It is often observed that mortality projections are more pessimistic when disaggregated by cause of death. This article explores the generality and strength of this relationship under a variety of forecasting models. First, a simple measure of the pessimism inherent in cause-based mortality forecasts is derived. Second, it is shown that the pessimism of cause-based forecasts can be approximated using only data on the distribution of deaths by cause in two pervious time periods. Third, using Japanese mortality data during 1951-1990, the analysis demonstrates that the pessimism of cause-based forecasts can be attributed mainly to observed trends in mortality due to cancer and heart disease, with smaller contribution due to trends in stroke (women only), pneumonia/bronchitis, accidents, and suicide. The last point requires the important qualification, however, that observed trends in cancer and heart disease may be severely biased due to changes in diagnostic practice." (SUMMARY IN FRE)     

Trends in U.S. adult chronic disease mortality, 1960–1999: age,period, and cohort variations

In this paper, I examine temporal changes in U.S. adult mortality by chronic disease cause of death and by sex over a 40-year period in the second half of the twentieth century. I apply age-period-cohort (APC) analyses that combine conventional approaches and a new method of model estimation to simultaneously account for age, period, and cohort variations in mortality rates for four leading causes of deaths, including heart disease, stroke, lung cancer, and breast cancer. The results show that large reductions in mortality since the late 1960s continued well into the late 1990s and that these reductions were predominately contributed by cohort effects. Cohort effects are found to differ by specific causes of death examined, but they generally show substantial survival improvements. Implications of these results are discussed with regard to demographic theories of mortality reductions, differential cohort accumulation of health capital and lifetime exposures to socioeconomic and behavioral risk factors, and period changes in diagnostic techniques and medical treatment.     

Economic Conditions in Early Life and Circulatory Disease Mortality

I test the Developmental Origins of Health and Disease hypothesis using a cohort perspective on mortality. I combine data from the National Health Interview Survey Linked Mortality Files, 1986–2006, and U.S. economic data between 1902 and 1956 (403,746 respondents and 39,439 deaths), to estimate how exposures to adverse economic conditions in utero and during the first three years of life affect circulatory disease mortality risk in adulthood. I also examine cohort‐based variation in these associations. Findings suggest that in utero exposures to poor economic conditions increased risk of death from circulatory diseases. Results are consistent with theory and evidence suggesting that developmental processes early in life are strongly associated with circulatory disease susceptibility in older adulthood. However, findings indicate that the mortality effects of these early‐life exposures have likely weakened across birth cohorts.     

Health,wartime stress,and unit cohesion: Evidence from Union Army veterans

We find that Union Army veterans of the American Civil War who faced greater wartime stress (as measured by higher battlefield mortality rates) experienced higher mortality rates at older ages, but that men who were from more cohesive companies were statistically significantly less likely to be affected by wartime stress. Our results hold for overall mortality, mortality from ischemic heart disease and stroke, and new diagnoses of arteriosclerosis. Our findings represent one of the first long-run health follow-ups of the interaction between stress and social networks in a human population in which both stress and social networks are arguably exogenous.     

The racial crossover in comorbidity, disability, and mortality

This study analyzed one respondent per household who was age 70 or more at the time of the household's inclusion in Wave 1 (1993-1994) and whose survival status was determinable at Wave 2 (1995-1996) of the Survey on Asset and Health Dynamics Among the Oldest Old (AHEAD Survey). At age 76 at Wave 1, there was a racial crossover in the cumulative number of six potentially fatal diagnoses (chronic lung disease, cancer, heart disease, hypertension, diabetes, and stroke) from a higher cumulative average number for blacks to a higher average number for whites. Also, there was a racial crossover at age 86 in the cumulative average number of disabilities in the Advanced Activities of Daily Living (AADLs), from a higher average for blacks to a higher average for whites. Between Waves 1 and 2, there was a racial crossover in the odds of mortality from higher odds for blacks to higher odds for whites; this occurred at about age 81. The results are consistent with the interpretation that the racial crossover in comorbidity (but not the crossover in AADL disability) propelled the racial crossover in mortality.     

Macroeconomic fluctuations and mortality in postwar Japan

Recent research has shown that after long-term declining trends are excluded, mortality rates in industrial countries tend to rise in economic expansions and fall in economic recessions. In the present work, co-movements between economic fluctuations and mortality changes in postwar Japan are investigated by analyzing time series of mortality rates and eight economic indicators. To eliminate spurious associations attributable to trends, series are detrended either via Hodrick-Prescott filtering or through differencing. As previously found in other industrial economies, general mortality and age-specific death rates in Japan tend to increase in expansions and drop in recessions, for both males and females. The effect, which is slightly stronger for males, is particularly noticeable in those aged 45-64. Deaths attributed to heart disease, pneumonia, accidents, liver disease, and senility--making up about 41% of total mortality--tend to fluctuate procyclically, increasing in expansions. Suicides, as well as deaths attributable to diabetes and hypertensive disease, make up about 4% of total mortality and fluctuate countercyclically, increasing in recessions. Deaths attributed to other causes, making up about half of total deaths, don't show a clearly defined relationship with the fluctuations of the economy.     

Cardiovascular and Tuberculosis Mortality: The Contrasting Effects of Changes in Two Causes of Death

Tuberculosis was the largest source of deaths among younger adults, and cardiovascular disease among older adults, in the America of 1900. Decreases in deaths from tuberculosis since 1900 and cardiovascular disease since 1940 explain most of the mortality drops in those age groups over the century. This article, building on previous work by White and Preston, shows the results of increased survival from these two causes on the US population structure. Standard demographic cause-specific mortality calculations are used to generate life tables without deaths from cardiovascular disease or tuberculosis. Then fixed rates for these diseases from early in the century are assumed while all other causes of death are allowed to change as they did historically. Improvements in cardiovascular mortality and tuberculosis produce some seemingly illogical contrasts. More people are alive today because of the decrease in tuberculosis. Yet more deaths from cardiovascular disease have been prevented, and cardiovascular improvements have raised life expectancy more. Lower tuberculosis mortality had virtually no effect on the average age of the population. Lower cardiovascular mortality alone has raised that average more than all twentieth-century causes of improved mortality combined.     

Causes of death to women of reproductive age in two developing countries

Data on cause of death are deficient for most developing countries. Nevertheless, it is important for policy makers to have access to such information to plan the use of resources and to evaluate health programs. In this study, deaths among women of reproductive age (15 to 49) in two areas in developing countries were located, and family members were interviewed. Local physicians reviewed the completed interviews and determined the cause of death.Complications of pregnancy and childbirth were the cause of 23% of the deaths in Menoufia, Egypt and Bali, Indonesia. In Egypt, the first cause of death was circulatory system disease (28%), followed by complications of pregnancy and childbirth (23%), and trauma (14%, primarily burns). In Indonesia, complications of pregnancy and childbirth was the first cause of death, followed by infectious disease (22%, primarily tuberculosis), and circulatory system disease (13%).Although the method of data collection was unorthodox, findings for Menoufia are comparable to data from other sources for the country as a whole. There are few data with which to compare our findings for Bali, but their similarity to the data from the Egyptian study lends credence to their quality.     

A healthy economy can break your heart

Panel data methods are used to investigate how deaths from coronary heart disease (CHD) in the United States vary with macroeconomic conditions. A one-percentage-point reduction in unemployment is predicted to raise CHD mortality by 0.75%, corresponding to almost 3900 additional fatalities. The increase in relative risk is similar across age groups, implying that senior citizens account for most of the extra deaths. Direct evidence is obtained of a role for decreases in medical interventions treating coronary problems. CHD mortality increases rapidly when the economy strengthens but returns to or near its baseline level within five years for most groups.     

The Contribution of Health Care and Other Interventions to Black–White Disparities in Life Expectancy, 1980–2007

Black–white mortality disparities remain sizable in the United States. In this study, we use the concept of avoidable/amenable mortality to estimate cause-of-death contributions to the difference in life expectancy between whites and blacks by gender in the United States in 1980, 1993, and 2007. We begin with a review of the concept of “avoidable mortality” and results of prior studies using this cause-of-death classification. We then present the results of our empirical analyses. We classified causes of death as amenable to medical care, sensitive to public health policies and health behaviors, ischemic heart disease, suicide, HIV/AIDS, and all other causes combined. We used vital statistics data on deaths and Census Bureau population estimates and standard demographic decomposition techniques. In 2007, causes of death amenable to medical care continued to account for close to 2 years of the racial difference in life expectancy among men (2.08) and women (1.85). Causes amenable to public health interventions made a larger contribution to the racial difference in life expectancy among men (1.17 years) than women (0.08 years). The contribution of HIV/AIDS substantially widened the racial difference among both men (1.08 years) and women (0.42 years) in 1993, but its contribution declined over time. Despite progress observed over the time period studied, a substantial portion of black–white disparities in mortality could be reduced given more equitable access to medical care and health interventions.     

Causes of death contributing to changes in life expectancy in New York City between 1983 and 1992

Recent changes in life expectancy among race and sex groups in New York City were evaluated by analyzing the relative effects of different causes of death in 1983 and 1992, a period in which life expectancy at birth declined by 1.1 years among white males, remained unchanged among black males, and increased 1.2 years among white and black females. Heart disease was found to be the leading cause of death making positive contributions to changes in life expectancy regardless of race or sex, and HIV/AIDS was the leading negative contributor. Overall, deaths from infectious diseases and external causes are becoming more important compared to degenerative conditions in explaining trends in life expectancy in New York City. Past improvements in survival due to reductions in infant deaths are being reversed due to an increase in deaths from preventable causes such as violence and AIDS. Future gains in longevity may require a greater emphasis on policies and programs emphasizing conflict resolution and HIV prevention.     

Demographic crisis: The impact of the Bangladesh civil war (1971) on births and deaths in a rural area of Bangladesh

Summary In Matlab Bazaar Thana the Cholera Research Laboratory has registered the births, deaths and migrations in a population of approximately 125,000 since 1966. Although this rural area was not the scene of any significant armed encounters, striking changes in birth and death rates were registered during and after the conflict. Birth rates did not change during the relatively brief period of the civil war, but a small decline was registered for one year after the war. Fertility rates which had been declining slightly and irregularly in the pre-war baseline period may have increased slightly during the war and fell substantially in all age groups in the year following the war. The crude death rate, which rose by 37 per cent during the war, was a very sensitive reflection of the administrative and economic problems. Overall infant mortality rose by only 15 per cent over pre-war levels because all of the increase was observed in the post-neo-natal component, which traditionally accounts for less than one-third of the total infant mortality in Bangladesh. Children and older adults accounted for the majority of excess deaths which were largely attributed to acute diarrhoeas and other gastro-intestinal causes. The death rate at ages 1-4 rose by 43 per cent and at ages 5-9 soared to 208 per cent above pre-war baseline rates. All increases in age-specific mortality rates fell to baseline levels during the year following the war, except the 5-9-year age group, in which rates continued to be high largely because of deaths due to dysentery.     

Understanding the age and cause drivers of recent longevity trends in Australia

Longevity continues to increase in Australia. The period 1979–2011 saw increases in life expectancy at birth of 6.9 years to 84.7 years for females, and 9.5 years to 80.2 years for males. A decomposition analysis reveals that the majority of the increase, particularly for females, is attributable to mortality improvement at older ages, and that gains are being made at increasingly older ages over time. Improvements in circulatory disease mortality account for a very significant component of life expectancy gains over the period—75 % for females and 60 % for males—with land transport accidents, congenital and perinatal mortality, and neoplasms also making significant positive contributions. Dementia and Alzheimer’s disease, and lung neoplasms for females, have had a negative impact. Females currently outlive males by 4.5 years on average, with ischaemic heart disease and prostate and other neoplasms the important positive contributors to this differential, and breast cancer having a negative effect. With 93 % of females and 88 % of males now surviving to age 65 in Australia, continued life expectancy improvements will depend to a large extent on success in delaying death at the older ages.     

Russian Mortality Crisis and the Quality of Vital Statistics

Mortality from ill-defined conditions in Russia has the fastest rate of increase compared to all other major causes of death. High proportion of deaths in this category is indicative for low quality of mortality statistics. This article examines the trends and possible causes of mortality from ill-defined conditions in Russia. During 1991–2005, mortality from ill-defined conditions in Russia increased in all age groups. The pace of increase was particularly high at working ages and the mean expected age at death from ill-defined conditions has shifted to younger ages, particularly for men. The analysis of individual medical death certificates issued in Kirov and Smolensk regions of Russia demonstrate that 89–100% of working-age deaths from ill-defined conditions correspond to human bodies found in a state of decomposition. Data from Smolensk region shows that over 60% of these decedents were unemployed. Temporal trends of mortality from ill-defined conditions and injuries of undetermined intent in Moscow city suggest that deaths from the latter cause were probably misclassified as ill-defined conditions. This practice can lead to underestimation of mortality from external causes. Growing number of socially isolated marginalized people in Russia and insufficient investigation of the circumstances of their death contribute to the observed trends in mortality from ill-defined conditions.