Looking Forward to a General Theory on Population Aging

The main theories on population aging based on recent data on human longevity, life expectancy, morbidity changes, disability trends, and mortality decrease are presented and discussed within their own geographic, cultural, socioeconomic, and medical contexts. The complex interactions between all these components do not facilitate trend forecasting of aging population (healthy aging versus disability pandemic). In the context of population aging, four elements were introduced with their implications: 1) an increase in the survival rates of sick persons, which would explain the expansion of morbidity, 2) a control of the progression of chronic diseases, which would explain a subtle equilibrium between the decrease in mortality and the increase in disability, 3) an improvement of the health status and health behaviors of new cohorts of elderly people, which would explain the compression of morbidity, and eventually 4) an emergence of very old and frail populations, which would explain a new expansion of morbidity. Obviously, all these elements coexist today, and future trend scenarios—expansion or compression of disability—depend on their respective weights leading to the need of elaborating "a general theory on population aging.” This theory has to be based on a world harmonization of functional decline measurements and a periodic "International Aging Survey” to monitor global aging through a sample of carefully selected countrie

The compression of deaths above the mode

Kannisto (2001) has shown that as the frequency distribution of ages at death has shifted to the right, the age distribution of deaths above the modal age has become more compressed. In order to further investigate this old-age mortality compression, we adopt the simple logistic model with two parameters, which is known to fit data on old-age mortality well (Thatcher 1999). Based on the model, we show that three key measures of old-age mortality (the modal age of adult deaths, the life expectancy at the modal age, and the standard deviation of ages at death above the mode) can be estimated fairly accurately from death rates at only two suitably chosen high ages (70 and 90 in this study). The distribution of deaths above the modal age becomes compressed when the logits of death rates fall more at the lower age than at the higher age. Our analysis of mortality time series in six countries, using the logistic model, endorsed Kannisto’s conclusion. Some possible reasons for the compression are discussed.compression of mortality, lexis model, logistic model, modal age of death, oldest old mortality decline, standard deviation

The use of the global activity limitation Indicator and healthy life years by member states and the European Commission

Background: In 2005, the European Union (EU) started to use a disability-free life expectancy, known as Healthy Life Years (HLY), to monitor progress in the strategic European policies such as the 2000 Lisbon strategy. HLY are based on the underlying measure: the Global Activity Limitation Indicator (GALI). Twelve years after its implementation, this study aims to assess its current use in EU Member States and the European Commission. Methods: In March 2017, a questionnaire was sent to 28 Member states and the European Commission. The questionnaire inquired how the GALI and HLY are used to set policy targets, in which surveys the GALI has been introduced since 2005, how the GALI and HLY are presented, and what the capacity in each country is to investigate the GALI and HLY. Results: The survey was answered by 22 Member States and by the Commission. HLY are often used to set targets and develop strategies in health such as national health plans. Analysis of HLY has even led to policy change. In some countries, HLY have become the main indicator for health, gaining more importance than life expectancy. More recently, the GALI and HLY have also been used for policy targets outside the health sector such as in the area of pension and retirement age or in the context of sustainable development. Regarding surveys, the GALI is mostly obtained from the EU-SILC, SHARE and EHIS, but is also increasingly introduced in national surveys. National health reporting systems usually present HLY on their national statistics websites. Most countries have up to three specialists working on the GALI and HLY, which has been consistent through time. Others have increased their capacity over various institutions. Conclusion: HLY is an indicator that is systematically used to monitor health developments in most EU countries. The SHARE, EU-SILC and EHIS are commonly used to assess HLY through the GALI. The results are then described in reports and presented on national statistics websites and used in different policy settings. Expertise to analyse the GALI and HLY is available in most countries

Harmonising summary measures of population health using global survey instruments.

measures of population health-health expectancies in particular-have become a standard for quantifying and monitoring population health. To date, cross-national comparability of health expectancies is limited, except within the European Union (EU). To advance international comparability, the European Joint Action on Healthy Life Years (JA: EHLEIS) set up an international working group. The working group discussed the conceptual basis of summary measures of population health and made suggestions for the development of comparable health expectancies to be used across the EU and Organisation for Economic Co-operation and Development (OECD) members. In this paper, which summarises the main results, we argue that harmonised health data needed for health expectancy calculation can best be obtained from 'global' survey measures, which provide a snapshot of the health situation using 1 or a few survey questions. We claim that 2 global measures of health should be pursued for their high policy relevance: a global measure of participation restriction and a global measure of functional limitation. We finally provide a blueprint for the future development and implementation of the 2 global measures. The blueprint sets the basis for subsequent international collaboration, having as a core group Member States of the EU, the USA and Japan. Other countries, in particular OECD members, are invited to join the initiative

Assessing the validity of the Global Activity Limitation Indicator in fourteen European countries.

BACKGROUND: The Global Activity Limitation Indicator (GALI), the measure underlying the European indicator Healthy Life Years (HLY), is widely used to compare population health across countries. However, the comparability of the item has been questioned. This study aims to further validate the GALI in the adult European population. METHODS: Data from the European Health Interview Survey (EHIS), covering 14 European countries and 152,787 individuals, were used to explore how the GALI was associated with other measures of disability and whether the GALI was consistent or reflected different disability situations in different countries. RESULTS: When considering each country separately or all combined, we found that the GALI was significantly associated with measures of activities of daily living, instrumental activity of daily living, and functional limitations (P < 0.001 in all cases). Associations were largest for activity of daily living and lowest though still high for functional limitations. For each measure, the magnitude of the association was similar across most countries. Overall, however, the GALI differed significantly between countries in terms of how it reflected each of the three disability measures (P < 0.001 in all cases). We suspect cross-country differences in the results may be due to variations in: the implementation of the EHIS, the perception of functioning and limitations, and the understanding of the GALI question. CONCLUSION: The study both confirms the relevance of this indicator to measure general activity limitations in the European population and the need for caution when comparing the level of the GALI from one country to another

Evaluating the performance of a climate-driven mortality model during heat waves and cold spells in Europe.

The impact of climate change on human health is a serious concern. In particular, changes in the frequency and intensity of heat waves and cold spells are of high relevance in terms of mortality and morbidity. This demonstrates the urgent need for reliable early-warning systems to help authorities prepare and respond to emergency situations. In this study, we evaluate the performance of a climate-driven mortality model to provide probabilistic predictions of exceeding emergency mortality thresholds for heat wave and cold spell scenarios. Daily mortality data corresponding to 187 NUTS2 regions across 16 countries in Europe were obtained from 1998-2003. Data were aggregated to 54 larger regions in Europe, defined according to similarities in population structure and climate. Location-specific average mortality rates, at given temperature intervals over the time period, were modelled to account for the increased mortality observed during both high and low temperature extremes and differing comfort temperatures between regions. Model parameters were estimated in a Bayesian framework, in order to generate probabilistic simulations of mortality across Europe for time periods of interest. For the heat wave scenario (1-15 August 2003), the model was successfully able to anticipate the occurrence or non-occurrence of mortality rates exceeding the emergency threshold (75th percentile of the mortality distribution) for 89% of the 54 regions, given a probability decision threshold of 70%. For the cold spell scenario (1-15 January 2003), mortality events in 69% of the regions were correctly anticipated with a probability decision threshold of 70%. By using a more conservative decision threshold of 30%, this proportion increased to 87%. Overall, the model performed better for the heat wave scenario. By replacing observed temperature data in the model with forecast temperature, from state-of-the-art European forecasting systems, probabilistic mortality predictions could potentially be made several months ahead of imminent heat waves and cold spells

Contribution of chronic diseases to the disability burden in a population 15 years and older, Belgium, 1997-2008.

BACKGROUND: Age-associated disability reduces quality of life in older populations and leads to wide-range implications for social and health policy. The identification of diseases that contribute to the disability burden is crucial to the development of prevention and intervention strategies to reduce disability. In this study, we assessed the contribution of chronic diseases to the prevalence of disability in Belgium. METHODS: Data from 35,837 individuals aged 15 years or older who participated in the 1997, 2001, 2004, or 2008 Belgian Health Interview Surveys were used. Disability was defined as difficulties in doing at least one of six activities of daily living (transfer in and out of bed, transfer in and out of chair, dressing, washing hands and face, feeding, and going to the toilet) and/or mobility limitations (ability to walk without stopping less than 200 m). Multiple additive regression models were fitted separately for men and women to estimate the age-specific background disability rate (experienced by everyone, independent of the presence of specific diseases) and disease-specific disability rates (disability rate in subjects who reported selected chronic diseases). RESULTS: Musculoskeletal, cardiovascular, and respiratory diseases were the main contributors to the disability burden in Belgium. Musculoskeletal diseases were the most prevalent diseases in men and women in all age groups. Neurological diseases and stroke were the most disabling diseases, i.e. caused the highest level of disability among the diseased individuals, in all age groups for men and women, respectively. Back pain was the main cause of disability in men aged 15 to 64 years, while heart attack was the major contributor to the disability prevalence in men aged 65 or older. Likewise, arthritis was the main cause of disability among women across all age groups. Depression was also an important contributor in young subjects (15-54 years). Cancer was not an important contributor to the disability prevalence in Belgium. CONCLUSIONS: To reduce the burden of disability in Belgium, interventions should target musculoskeletal, cardiovascular and respiratory diseases especially among elderly. Furthermore, attention should also be given to depression in young individuals

Contribution of chronic diseases to the disability burden in a population 15 years and older, Belgium, 1997-2008

Background: Age-associated disability reduces quality of life in older populations and leads to wide-range implications for social and health policy. The identification of diseases that contribute to the disability burden is crucial to the development of prevention and intervention strategies to reduce disability. In this study, we assessed the contribution of chronic diseases to the prevalence of disability in Belgium. Methods: Data from 35,837 individuals aged 15 years or older who participated in the 1997, 2001, 2004, or 2008 Belgian Health Interview Surveys were used. Disability was defined as difficulties in doing at least one of six activities of daily living (transfer in and out of bed, transfer in and out of chair, dressing, washing hands and face, feeding, and going to the toilet) and/or mobility limitations (ability to walk without stopping less than 200 m). Multiple additive regression models were fitted separately for men and women to estimate the age-specific background disability rate (experienced by everyone, independent of the presence of specific diseases) and disease-specific disability rates (disability rate in subjects who reported selected chronic diseases). Results: Musculoskeletal, cardiovascular, and respiratory diseases were the main contributors to the disability burden in Belgium. Musculoskeletal diseases were the most prevalent diseases in men and women in all age groups. Neurological diseases and stroke were the most disabling diseases, i.e. caused the highest level of disability among the diseased individuals, in all age groups for men and women, respectively. Back pain was the main cause of disability in men aged 15 to 64 years, while heart attack was the major contributor to the disability prevalence in men aged 65 or older. Likewise, arthritis was the main cause of disability among women across all age groups. Depression was also an important contributor in young subjects (15-54 years). Cancer was not an important contributor to the disability prevalence in Belgium. Conclusions: To reduce the burden of disability in Belgium, interventions should target musculoskeletal, cardiovascular and respiratory diseases especially among elderly. Furthermore, attention should also be given to depression in young individuals