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J J Barendregt

Publications and source records attributed to J J Barendregt.

At least 19 recordsLinked to original sources
PubMed2001

Stochastic league tables: communicating cost-effectiveness results to decision-makers.

The presentation of the results of uncertainty analysis in cost-effectiveness analysis (CEA) in the literature has been relatively academic with little attention paid to the question of how decision-makers should interpret the information particularly when confidence intervals overlap. This question is especially relevant to sectorial CEA providing information on the costs and effects of a wide range of interventions. This paper introduces stochastic league tables to inform decision-makers about the probability that a specific intervention would be included in the optimal mix of interventions for various levels of resource availability, taking into account the uncertainty surrounding costs and effectiveness. This information helps decision-makers decide on the relative attractiveness of different intervention mixes, and also on the implications for trading gains in efficiency for gains in other goals such as reducing health inequalities and increasing health system responsiveness.

Communication↗
PubMed2000

An indirect estimate of the incidence of non-insulin-dependent diabetes mellitus.

Our goal was to estimate non-insulin-dependent diabetes mellitus incidence in the Netherlands in the absence of equivocal empirical data. Incidence can be expressed as a function of age, sex, prevalence, and mortality. We obtained prevalence data from a study that pooled existing prevalence estimates. We calculated diabetes-related mortality using relative risks on all-cause mortality. Sensitivity for the rate of excess mortality was determined using the 95% confidence intervals (95% CI) of the relative risks. The estimated incidence increases exponentially with age, with a doubling time of 10 years for men and 9 years for women. The rate increases from 8.1 per 10,000 (95% CI = 7.7-8.8) for men ages 40-44 years and 7.0 (95% CI = 6.8-8.0) for women to 79.7 per 10,000 (95% CI = 69.5-90.9) for men ages 75-79 years and 85.8 (95% CI = 80.6-91.0) for women. When empirical estimates of incidence are largely lacking, the methodology described offers a useful alternative, in particular for the assessment of potential intervention effects.

Adolescent↗
PubMed1999

[Primary prevention remains expensive, notwithstanding the consensus on lowering serum cholesterol levels].

Recently guidelines for cholesterol lowering therapy by means of 'statines' (HMG-CoA reductase inhibitors) were published by the National Organization of Quality Assurance in Hospitals. The part about primary prevention of cardiovascular disease is based on absolute risks for coronary heart disease as calculated by the Framingham Heart Study risk functions and on a cost-effectiveness analysis. However, the function predicts risk of disease such as silent infarction and angina pectoris. The incidence thus produced is higher than any observed clinical incidence. Absolute risk increases exponentially with age, but remaining life expectancy, and thus benefit, decreases. Therefore, decisions about treatment levels are based on arbitrary assumptions. The function is ultimately only used to advise treatment to the smoker, while the better choice is always to stop smoking. The effectiveness is overestimated by using a long time horizon of treatment of 25 years in the cost-effectiveness analysis. Primary prevention of coronary heart disease according to the new guidelines is still very expensive.

Adult↗
PubMed1999

The new old epidemic of coronary heart disease.

OBJECTIVES: This study quantified the consequences for prevalence of increased survival of coronary heart disease (CHD) in the Netherlands from 1980 to 1993. METHODS: A multistage life table fitted observed mortality and registration rates from the nationwide hospital register. The outcome was prevalence by age, sex, period, and disease state. RESULTS: The prevalence of CHD from 1980 to 1993 was 4.4% (men, aged 25 to 84 years) and 1.4% (women, aged 25 to 84 years). Between 1980-1983 and 1990-1993, the incidence changed little, but age-adjusted prevalence increased by 19% (men) and 59% (women). CONCLUSIONS: Sharply decreasing mortality but near-constant attack rates of CHD caused distinct increases in prevalence, particularly among the elderly.

Adult↗
PubMed1999

The burden of mortality of diabetes mellitus in The Netherlands.

Our objective was to estimate the excess mortality and the reduction in life expectancy related to diabetes mellitus. We developed a life table to describe the Dutch population in two states, diabetic and non-diabetic, using age- and sex-specific prevalence of diabetes mellitus and risks of dying for diabetic subjects. We compared the calculated excess deaths with registered deaths. The cause-of-death registration practice underestimates diabetes-related mortality. The method used in this study, combining mortality data with data from epidemiologic studies, provides an assessment of the impact of diabetes on the Dutch population.

Aged↗
PubMed1998

Preventing fatal diseases increases healthcare costs: cause elimination life table approach.

OBJECTIVES: To examine whether elimination of fatal diseases will increase healthcare costs. DESIGN: Mortality data from vital statistics combined with healthcare spending in a cause elimination life table. Costs were allocated to specific diseases through the various healthcare registers. SETTING AND SUBJECTS: The population of the Netherlands, 1988. MAIN OUTCOME MEASURES: Healthcare costs of a synthetic life table cohort, expressed as life time expected costs. RESULTS: The life time expected healthcare costs for 1988 in the Netherlands were 56,600 Pounds for men and 80,900 Pounds for women. Elimination of fatal diseases--such as coronary heart disease, cancer, or chronic obstructive lung disease--increases healthcare costs. Major savings will be achieved only by elimination of non-fatal disease--such as musculoskeletal diseases and mental disorders. CONCLUSION: The aim of prevention is to spare people from avoidable misery and death not to save money on the healthcare system. In countries with low mortality, elimination of fatal diseases by successful prevention increases healthcare spending because of the medical expenses during added life years.

Accidents↗
PubMed1998

The expiry date of man: a synthesis of evolutionary biology and public health.

In industrialised countries, mortality and morbidity are dominated by age related chronic degenerative diseases. The health and health care needs of future populations will be heavily determined by these conditions of old age. Two opposite scenarios of future morbidity exist: morbidity might decrease ("compress"), because life span is limited, and the incidence of disease is postponed. Or morbidity might increase ("expand"), because death is delayed more than disease incidence. Optimality theory in evolutionary biology explains senescence as a by product of an optimised life history. The theory clarifies how senescence is timed by the competing needs for reproduction and survival, and why this leads to a generalised deterioration of many functions at many levels. As death and disease are not independent, future morbidity will depend on duration and severity of the process of senescence, partly determined by health care, palliating the disease severity but increasing the disease duration by postponing death. Even if morbidity might be compressed, health care needs will surely expand.

Aging↗
PubMed1997

The health care costs of smoking.

BACKGROUND: Although smoking cessation is desirable from a public health perspective, its consequences with respect to health care costs are still debated. Smokers have more disease than nonsmokers, but nonsmokers live longer and can incur more health costs at advanced ages. We analyzed health care costs for smokers and nonsmokers and estimated the economic consequences of smoking cessation. METHODS: We used three life tables to examine the effect of smoking on health care costs - one for a mixed population of smokers and nonsmokers, one for a population of smokers, and one for a population of nonsmokers. We also used a dynamic method to estimate the effects of smoking cessation on health care costs over time. RESULTS: Health care costs for smokers at a given age are as much as 40 percent higher than those for nonsmokers, but in a population in which no one smoked the costs would be 7 percent higher among men and 4 percent higher among women than the costs in the current mixed population of smokers and nonsmokers. If all smokers quit, health care costs would be lower at first, but after 15 years they would become higher than at present. In the long term, complete smoking cessation would produce a net increase in health care costs, but it could still be seen as economically favorable under reasonable assumptions of discount rate and evaluation period. CONCLUSIONS: If people stopped smoking, there would be a savings in health care costs, but only in the short term. Eventually, smoking cessation would lead to increased health care costs.

Adolescent↗
PubMed1997

[Future increase of the incidence of mesothelioma due to occupational exposure to asbestos in the past].

OBJECTIVE: To estimate the future course of mesothelioma mortality as a result of occupational exposure to asbestos in the past. DESIGN: Cohort age model. SETTING: Department of Public Health, Erasmus University Rotterdam, the Netherlands. METHODS: A cohort age model was developed, based upon age-specific rates of pleural mesothelioma mortality during 1969-1994. This model was linked to the future trend in mortality among Dutch men as projected by the Central Bureau for Statistics in order to predict the future course of mesothelioma mortality in the period 1995-2030. RESULTS: In the next 35 years about 20,000 cases of pleural mesothelioma among men are expected. The projection results in a peak of annual male mesothelioma deaths of approximately 700 in about the year 2018. After 2020 the annual mortality will rapidly decline to about 450 cases in 2030. It is expected that this rapid decline will continue after 2030. In the 1943-1947 birth cohort pleural mesothelioma may account for 0.87% of all deaths. Exposure to asbestos at work largely explains this particular mortality pattern. CONCLUSION: Exposure to asbestos at work has created an important public health problem among Dutch men.

Asbestos↗
PubMed1997

Regression analysis of recent changes in cardiovascular morbidity and mortality in The Netherlands.

OBJECTIVES: To test whether recent declines in mortality from coronary heart disease were associated with increased mortality from other cardiovascular diseases. DESIGN: Poisson regression analysis of national data on causes of death and hospital discharges. SETTING AND SUBJECTS: Population of the Netherlands, 1969-93. MAIN OUTCOME MEASURES: Annual changes in mortality from coronary heart disease, stroke, and other cardiovascular diseases and annual changes in hospital discharge rates for acute coronary events, stroke, and congestive heart failures. RESULTS: Patterns of cardiovascular mortality changed abruptly in 1987-93. Annual decline in mortality from coronary heart disease increased sharply for women and men: from -1.9% (95% confidence interval -2.2% to -1.6%) and -1.7% (-1.9% to -1.4%) respectively in 1979-86 to -3.1% (-3.5% to -2.6%) and -4.2% (-4.6% to -3.9%) in 1987-93. The longstanding decline in mortality from stroke levelled off: from annual change of -3.3% (-3.7% to -2.8%) and -3.2% (-3.7% to -2.8%) in 1979-86 to -0.1% (-0.7% to 0.4%) and -1.1% (-1.7% to -0.5%) in 1987-93. Mortality from other cardiovascular diseases, however, started to increase: from -2.0% (-2.4% to -1.6%) and -0.2% (-0.5% to 0.2%) in 1979-86 to 1.5% (1.0% to 2.0%) and 1.9% (1.5% to 2.3%) in 1987-93. Hospital discharge rates for acute coronary heart disease, congestive heart failure, and stroke increased during 1980-6. During 1987-93 discharge rates for stroke and coronary heart disease stabilised but rates for congestive heart failure increased. CONCLUSION: Improved management of coronary heart disease seems to have reduced mortality, but some of the gains are lost to deaths from stroke and other cardiovascular diseases. The increasing numbers of patients with coronary heart disease who survive will increase demands on health services for long term care.

Cardiovascular Diseases↗
PubMed1996

[Aging as a cause of hip fractures; a theoretic mathematical model].

OBJECTIVE: To estimate the numbers of hip fractures among Dutch women caused by senescence in contrast to decreasing postmenopausal bone loss. DESIGN: A Markov chain model in a multi-state life table. SETTING: Department of Public Health, Erasmus University of Rotterdam, the Netherlands. METHOD: Cross-sectional data of prevalences of femoral neck bone mineral density, measured in an epidemiological survey (1993), were related to numbers of hospital admissions for hip fractures among women aged 55 and older, using a (published) relative risk for hip fracture of 2.6 (95% confidence limits: 1.9-3.6) per decrease by I SD of bone mineral density. We varied the prevalences of bone mineral density in the multi state life table and looked at changes in the expected number of fractures. RESULTS: If bone loss were to cease after the age of 55, this would decrease the number of fractures by 39.4% (30.4%-45.2% in sensitivity analysis). If bone loss were delayed by 7.5 years, the number of hip fractures would decrease by 14.8% (10.0%-19.9% after 5 to 10 years' delay). If compliance decreases by age (3% per year), then the number of hip fractures would decrease by 5.6% (3.4%-11.0% after 1%-5% decrease of compliance per year). CONCLUSION: Bone loss is only one of the many age related causes of hip fractures. Population based interventions targeting only bone mineral density, while ignoring comorbidity, have only a limited potential for preventing hip fractures.

Aged↗
PubMed1996

DALYs: the age-weights on balance.

In studies for the 1993 World development report: investing in health Murray et al. developed the disability-adjusted life year (DALY). This article examines one particular aspect of the DALY methodology: the weighting of life years by age. For the quantitative implementation of this notion Murray proposed a general equation to weight life years by age, which specifies that the years lived between the ages of 9 and 54 years have a weight greater than unity, and for the years outside this range less than unity. The age-weighted life years are used to calculate the "expected years of life lost" (EYLL). Comparison of age-weighted and unweighted age-specific life expectancies shows that the age range which becomes more important due to weighting is not 9-54 years, but 0-27 years. This happens because the EYLL is an age-weighting system in itself, emphasizing the young. The result of piling one age-weighting system on top of the other gives an even stronger emphasis on the young than the EYLL generates by itself. Although this is unlikely to upset the results from the Global Burden of Disease study, we do not think it is desirable. And it is certainly different from what we were led to expect.

Adolescent↗
PubMed1995

Diverging trends in colorectal cancer morbidity and mortality. Earlier diagnosis comes at a price.

In developed countries, time trends in the incidence of colorectal cancer differ markedly from trends in mortality. This study sought to explain simultaneously changes in both colorectal cancer incidence and mortality. Data on first admissions, interventions and outcome from the national hospital registry over the period 1978-1989 and data on mortality from Statistics Netherlands over the same period were analysed by age-period models and subsequently entered in a Markov chain model, simulating disease history from first admission to death. Over the period 1978-1989, age adjusted numbers of first admissions and interventions increased by 37% and 32%, respectively, while mortality declined by 8%. For every 100 patients admitted between 1987 and 1989, 13 more will survive compared with 1978-1980. Of these, 3 will be saved by improving results of primary treatment but the other 10 will survive their diagnosis for the subsequent 10 years. Although progress in treatment has been made, therapeutic improvement can account only for the smaller part of the divergence between morbidity and mortality. Increased diagnostic activity, raising incidence and lowering mortality simultaneously, is the most likely cause of the unexplained divergence.

Adult↗