Forget the red Porsches, promiscuous escapades, and questionable clothing choices. The real marker of a midlife crisis seems to be a much more serious issue that is difficult to treat, and Americans appear to deal with it more often than their peers.

In the late 1950s, a psychoanalyst named Elliott Jaques was the first to argue that people in their mid-thirties, primarily men, could experience a yearslong bout of depression brought on by the realization of one’s own mortality. Thus, the “midlife crisis” was born, exhibited by a sudden urge to seize control of respective circumstances and to reinvent oneself in increasingly improbable ways.

Because of longer life expectancies, the onset of symptoms thankfully was not static at 35, but regardless of when people entered their midlife crisis, evidence of the phenomenon was observed around the world. Jaques himself was Canadian-born, and he first presented his thesis in 1957 to the British Psychoanalytical Society in London. But in the decades since, as some countries have taken steps toward reducing the burden of midlife depression in their society, mental health for the middle-aged has become a distinctly American problem.

While middle-aged adults in many modern nations are seeing their health and well-being stabilize or even improve, Americans born between the 1930s and 1970s are comparatively faring much worse, according to a study published Monday in the journal Current Directions in Psychological Science, led by researchers at Arizona State University. Leading the list of afflictions are unprecedented levels of loneliness, depression, and cognitive decline.