Death rates from suicide, drug overdoses, liver disease and dozens of other causes have been rising over the past decade for young and middle-aged adults, driving down overall life expectancy in the United States for three consecutive years, according to a strikingly bleak study published Tuesday that looked at the past six decades of mortality data.

The report, published in the Journal of the American Medical Association, was immediately hailed by outside researchers for its comprehensive treatment of a still-enigmatic trend: the reversal of historical patterns in longevity.

The United States, despite massive expenditures on health care, has seen increasing mortality and falling life expectancy for people ages 25 to 64, who should be in the prime of their lives, while other wealthy nations have generally experienced continued progress in extending longevity. Although earlier research emphasized rising mortality among non-Hispanic whites, the broad trend detailed in this study cuts across gender, racial and ethnic lines. By age group, the highest relative jump in death rates from 2010 to 2017 - 29% - has been among people ages 25 to 34.