Michel Guillot

The burden of disease among the global poor

BACKGROUND Global and regional estimates show that non-communicable diseases in old age are rising in importance relative to other causes of ill health as populations age, and as progress continues against communicable diseases among infants and children. However, these estimates, which cover population groups at all income levels, do not accurately reflect conditions that prevail among the poor. We estimated the burden of disease among the 20% of the global population living in countries with the lowest per capita incomes, compared with the 20% of the worlds people living in the richest countries. METHODS Estimates for the global poorest and richest 20% were prepared for 1990 for deaths and disability-adjusted life years (DALYs), by a procedure used in a prominent recent study of the global disease burden. Projected mortality rates in the year 2020 were established for the worlds poorest and richest 20% under various assumptions about the future rate of decline in communicable and non-communicable diseases. FINDINGS In 1990, communicable diseases caused 59% of death and disability among the worlds poorest 20%. Among the worlds richest 20%, on the other hand, non-communicable diseases caused 85% of death and disability. A raised baseline rate of communicable disease decline between 1990 and 2020 would increase life-expectancy among the worlds poorest 20% around ten times as much as it would the richest 20% (4.1 vs 0.4 years). However, the poorest 20% would gain only around a quarter to a third as much as the richest 20% from a similar increase in non-communicable diseases (1.4 vs 5.3 years). As a result, a faster decline in communicable diseases would decease the poor-rich gap in 2020, but under an accelerated rate of overall decline in non-communicable diseases, the poor-rich gap would widen. INTERPRETATION Our estimates are crude, but despite their limitations, they give a more accurate picture of changes in attributable mortality among the worlds poor than do the global averages in current use.

Modified logit life table system: principles, empirical validation, and application

Despite its widespread use, the Coale-Demeny model life table system does not capture the extensive variation in age-specific mortality patterns observed in contemporary populations, particularly those of the countries of Eastern Europe and populations affected by HIV/AIDS. Although relational mortality models, such as the Brass logit system, can identify these variations, these models show systematic bias in their predictive ability as mortality levels depart from the standard. We propose a modification of the two-parameter Brass relational model. The modified model incorporates two additional age-specific correction factors ( γx and θ x ) based on mortality levels among children and adults, relative to the standard. Tests of predictive validity show deviations in age-specific mortality rates predicted by the proposed system to be 30-50 per cent lower than those predicted by the Coale-Demeny system and 15-40 per cent lower than those predicted using the original Brass system. The modified logit system is a two-parameter system, parameterized using values of l 5 and l 60 .

The cross-sectional average length of life (CAL): A cross-sectional mortality measure that reflects the experience of cohorts

This paper presents a summary mortality index, the cross-sectional average length of life (CAL). By combining the mortality experience of various cohorts in a cross-sectional fashion, CAL complements traditional one-period or one-cohort indexes and enriches our understanding of population processes. First, CAL provides an alternative insight into the analysis of mortality. By taking into account the real mortality conditions to which individuals in a population have been subject, it tends to yield less favourable mortality levels than e0 and produces different rankings of mortality levels across countries. Second, CAL is a relevant index for the study of population dynamics. In particular, change in CAL over time shows the direct impact of mortality change on population growth, and the e0/CAL ratio for a given year shows the mortality-induced growth that can be expected given current mortality levels. It illustrates that mortality can play a non-negligible role in future population growth, even in the absence of future mortality improvements.

Tempo effects in mortality: An appraisal

This study examines the existence of tempo effects in mortality and evaluates the procedure developed by Bongaarts and Feeney for calculating a tempo-adjusted life expectancy. It is shown that the performance of Bongaarts and Feeney’s index as an indicator reflecting current mortality conditions depends primarily on specific assumptions regarding the effects of changing period mortality conditions on the timing of future cohort deaths. It is argued that, currently, there is no clear evidence about the existence of such effects in actual populations. This paper concludes that until the existence of these effects can be demonstrated, it is preferable to continue using the conventional life expectancy as an indicator of current mortality conditions 1Center for Demography and Ecology, University of Wisconsin-Madison, 1180 Observatory Drive, Madison, WI 53706, USA. E-mail: mguillot@ssc.wisc.edu http://www.demographic-research.org 1 Guillot: Tempo effects in mortality

Child mortality estimation: A global overview of infant and child mortality age patterns in light of new empirical data.

Michel Guillot and colleagues did a systematic evaluation to assess what proportion of under-five mortality occurs below age one compared with at age one and above, to determine how much observed values deviate from so called “model age patterns” of under-five mortality

The dynamics of the population sex ratio in India, 1971¿96

This paper reconstructs the trend in the population sex ratio in India between 1971 and 1996 from available information on changes in sex differentials in mortality in the country since the beginning of the century. It is estimated that, although the mortality of females relative to that of males in India has improved since 1968, the population sex ratio increased between 1971 and 1981, stayed constant between 1981 and 1991, and started to decrease only after 1991. This implies that the recorded decrease and increase in the periods 1971–81 and 1981–91 respectively were both spurious and were the results of undercounts of females in 1971 and 1991. Another implication of this finding is that, owing to the lagged effect of past mortality on current trends in the population sex ratio, this ratio is a bad proxy for use in the study of changes in differential mortality by sex.

Understanding the “Russian Mortality Paradox” in Central Asia: Evidence from Kyrgyzstan

In the former Soviet republics of central Asia, ethnic Russians have exhibited higher adult mortality than native ethnic groups (e.g., Kazakh, Kyrgyz, Uzbek) in spite of the higher socioeconomic status of ethnic Russians. The mortality disadvantage of ethnic Russians at adult ages appears to have even increased since the breakup of the Soviet Union. The most common explanation for this “Russian mortality paradox,” is that deaths are better reported among ethnic Russians. In this study, we use detailed mortality data from Kyrgyzstan between 1959 and 1999 to evaluate various explanations for the Russian mortality paradox: data artifacts, migration effects, and cultural effects. We find that the most plausible explanation is the cultural hypothesis because the personal behaviors that appear to generate a large part of the observed mortality differences (alcohol consumption, in particular) seem to be closely tied to cultural practices. We examine the implications of this finding for understanding the health crisis in post-Soviet states.

The momentum of mortality change.

Mortality change is not usually assigned much importance as a source of population growth when future population trends are discussed. Yet it can make a significant contribution to population momentum. In populations that have experienced mortality change, cohort survivorship will continue varying for some time even if period mortality rates become constant. This continuing change in cohort survivorship can create a significant degree of mortality-induced population change, a process we call the ‘momentum of mortality change’. The momentum of mortality change can be estimated by taking the ratio of e 0 (the period life expectancy at birth) to CAL (the cross-sectional average length of life) for a given year. In industrialized nations, the momentum of mortality change can attenuate the negative effect on population growth of declining fertility or sustained below-replacement fertility. In India, where population momentum has a value of 1.436, the momentum of mortality change is the greatest contributor to its value.

Infant mortality in Kyrgyzstan before and after the break-up of the Soviet Union

There is a great deal of uncertainty over the levels of, and trends in, infant mortality in the former Soviet republics of Central Asia. As a result, the impact of the break-up of the Soviet Union on infant mortality in the region is not known, and proper monitoring of mortality levels is impaired. In this paper, a variety of data sources and methods are used to assess levels of infant mortality and their trend over time in one Central Asian republic, Kyrgyzstan, between 1980 and 2010. An abrupt halt to an already established decline in infant mortality was observed to occur during the decade following the break-up of the Soviet Union, contradicting the official statistics based on vital registration. Infants of Central Asian ethnicity and those born in rural areas were also considerably more at risk of mortality than suggested by the official sources. We discuss the implications of these findings, both for health policy in this seldom studied part of the former Soviet Union and for our understanding of the health crisis which it currently faces.

Divergent Paths for Adult Mortality in Russia and Central Asia: Evidence from Kyrgyzstan

Adult mortality has been lower in Kyrgyzstan vs. Russia among males since at least 1981 and among females since 1999. Also, Kyrgyzstan’s mortality fluctuations have had smaller amplitude. This has occurred in spite of worse macro-economic outcomes in Kyrgyzstan. To understand these surprising patterns, we analyzed cause-specific mortality in Kyrgyzstan vs. Russia for the period 1981-2010, using unpublished official data. We find that, as in Russia, fluctuations in Kyrgyzstan have been primarily due to changes in external causes and circulatory causes, and alcohol appears to play an important role. However, in contrast with Russia, mortality from these causes in Kyrgyzstan has been lower and has increased by a smaller amount. As a result, the mortality gap between the two countries is overwhelmingly attributable to external and cardio-vascular causes, and more generally, to causes that have been shown to be strongly related to alcohol consumption. These cause-specific results, together with the existence of large ethnic differentials in mortality in Kyrgyzstan, highlight the importance of cultural and religious differences, and their impact on patterns of alcohol consumption, in explaining the mortality gap between the two countries. These findings show that explanatory frameworks relying solely on macro-economic factors are not sufficient for understanding differences in mortality levels and trends among former Soviet republics.