Age-specific mortality analysis helps to explain all-cause mortality decline in Kazakhstan

Background In Kazakhstan, all-cause mortality declined by almost 20% between 2007 and 2012. This steep decline was the first sustained improvement in all-cause mortality in the country since the steep increases in mortality after the collapse of the Soviet Union in 1991. We hypothesize that reduced alcohol consumption was a major reason for the observed improvements. Methods Age-specific mortality rates in Kazakhstan from all-cause mortality, both for men and women, were derived from the WHO mortality database and analysed for the age groups 25-34, 35-54, 55-74, and 75+ for the period of 2007-2012. Results The decline in all-cause mortality was steepest in younger age groups, and much less pronounced or even barely detectable in older age groups. The mortality decline in the 25-34 age group was 42% for men and 37% for women, compared to 29% and 20% in the age group 35-54, and a decline of 18% and 16% respectively in the 55-74 age group. In the age group 75+, the decline was only 3% for men and 1% for women. Annual percentage changes were 9.2% for men and 8.2% for women in the 25-34 group; 6.6% and 4.7% respectively in the 35-54 group, 4.3% and 3.8% in the 55-74 group; and 0.7% and 0.4% in the 75+ group. The trends are in sharp contrast to mortality declines in Western Europe, where the biggest gains were observed in older age groups. Conclusions The sharp decline in all-cause mortality in younger age groups and the less pronounced decline in older age groups is consistent with the hypothesis that alcohol consumption was the main factor influencing the decline. Consistent policy measures on reduced alcohol consumption, such as through sustained tax increases, should be continued to sustain mortality declines. Key messages: The analysis of age-specific mortality can inform research and policy action to reduce premature mortality in Kazakhstan and other former USSR countries, where similar mortality trends can be observed