Mortality is falling in the global South but inequalities persist

In an article published in Population (2017-2), Dominique Tabutin and Bruno Masquelier assess mortality trends in 108 low- and middle-income countries and examine how inequalities in mortality have evolved since 1990.

Two of the article’s main focuses are life expectancy and child mortality levels.

Life expectancy trends

From 1990 to 2015, life expectancy at the global level rose from 64 to 71 years; in middle-income countries it rose from 63 to 70 years, and in low-income countries from 49 to 61 years. All the major regions of the world experienced considerable gains but inequalities between them remain substantially the same. Sub-Saharan Africa is still 17 years behind Latin America and 10 years behind Southern Asia.

Évolution de l’espérance de vie à la naissance (sexes réunis) de 108 pays du Sud de 1990 à 2015, selon leur niveau de revenu.
Source : Nations Unies (2015).

In all but ten countries, life expectancy rose, but the number of years gained varies from 2 at the lowest end of the scale to 18 at the highest; the most commonly found gain was 6 or 7 years. Inequalities between countries, already spectacular in 1990 (37 and 76 years at the extremes), remain so in 2015 (49 and 80). The six countries in which life expectancy either remained stable or fell over the period were countries particularly hard-hit by AIDS or war (Syria since 2011).

Overall, the life expectancy of a country’s inhabitants is related to its income level. But poor countries have caught up to some degree: life expectancy in the poorest countries improved more rapidly than in all other types over the 25-year period, with average annual gains of 0.5 years as against 0.28 years.


Infant and child mortality

Gains have been particularly strong among children. According to UNICEF (2015), the number of deaths under 5 years of age fell from 12.7 million in 1990 to 5.9 million in 2015, and mortality risk for the same group fell from 91 to 43 deaths per 1,000 births. Nearly 98% of those deaths are now concentrated in low- and middle-income countries.

Évolution des quotients de mortalité infanto-juvénile entre 1990 et 2015 dans les 108 pays à faible et moyen revenu.
Source : UN IGME (2015).

Mortality among children aged 1 to 5 has decreased more quickly than any other, as this is an age group particularly receptive to improvements in public health and welfare. At the lower end (Sub-Saharan and North Africa), child mortality fell by 65%; at the upper end (eastern Asia) by as high as 84%. However, at under one month of age, children are particularly vulnerable and least receptive to medical treatment due to the nature of the risks involved and the cost of care; mortality among infants in these first weeks of life—neonatal mortality—declined more slowly. These differences have gradually concentrated infant mortality in the first weeks of life: in 2015, 45% of infant deaths in low- and middle-income countries occurred in the first 28 days.

One encouraging point is the acceleration of change in the 2000s, particularly from 2005 on. In approximately 20 countries, including some of the world’s poorest, mortality declined twice as fast after 2004; this was the case for Cambodia, Kenya, Senegal, Burkina Faso and Mexico. In countries severely affected by AIDS, the recent acceleration in the decline of the mortality rate can be attributed in part to programmes for preventing mother-to-child transmission of the HIV virus and diffusion of antiretroviral treatments. Elsewhere it is due above all to renewed vaccination campaigns, purification of and improved access to drinking water, and the use of insecticide-treated mosquito nets to combat infection by malaria.

Most countries today have attained mortality rates much lower than those predicted for them 15 or 20 years ago, and this is particularly true of very poor countries. The considerable falls affect all ages but especially young children. They have also benefited young girls and women and all social groups, though the rate of improvement varies greatly by country. What can we expect in the future, in new and emerging epidemiological contexts where non-contagious, behavior-dependent diseases (nutrition, drinking, smoking and others) and environment-related diseases (pollution) together with population ageing will explain increasing shares of mortality? In a context of escalating macroeconomic inequalities, health system privatization in some countries and rising living expenses, there is reason to fear that inequalities between countries and social groups within them will either remain stable or widen.

Source: Bruno Masquelier et Dominique Tabutin, 2017, Mortality Inequalities and Trends in Low- and Middle-Income Countries,1990-2015, Population 2017, 2.

Contacts: Bruno Masquelier et Dominique Tabutin

Online: November 2017