During one of the greatest economic booms in the history of the world, working-age men had trouble staying alive.

That is the disheartening news from China, where its insurance regulator recently updated a more-than 10-year-old table of mortality rates. A key finding: Mortality rates among Chinese men aged 41 to 60, who account for nearly three-quarters of the working-age population, increased by 12% over the decade through 2013, the most recent data available. This was even as mortality rates generally improved across other age groups and genders.

It could be that financial success breeds bad health habits. Disposable income per capita has risen 90% in the past six years and probably more than that over the past decade, though official government data is limited. Chinese liquor consumption—where men consume 60% more than women—has risen 5% compounded annually over the past 15 years, considered fast by global standards, according to Bernstein analysts. Richer diets go along with high incidence of lung and coronary issues for Chinese men.