If it's true that salaried employees are more at risk due to Japan's labor shortage, then certainly being overworked can contribute to more early deaths. Despite Japan's critical labor shortage, some employers won't hire, insisting that existing employees work longer and harder. Salaried employees can certainly suffer more in such circumstances as, although their salary may be based on a certain of hours a week, an employer can insist that they take on more work and work more hours without offering more benefits, more money or compensatory time off.
In Japan, there's not even a term for "work-life balance". What there is, though, is a word for "death by overwork." It's "karoshi", and it's considered such an inevitable result of Japan's notoriously gruelling work culture that it's hardly even discussed. But every year here, hundreds, maybe thousands, of Japanese people literally work themselves to death.
I just watched a show on this the other day. A young father left for work looking exhausted. It was reported later that there was an issue at the company and that his superiors did not respond to requests for help. He had a heart attack; he was 30 years old. There needs to be more public awareness in that country so it doesn't keep happening.
Trends either fall or rise, no matter by what degree. I can't imagine Karoshi is declining in Japan. In this current economy, in a setting where manual labor is the norm, combined with the characteristic of a notoriously hard-working race of people, I can,t imagine this trend would do anything but increase as people strive to maintain or improve their quality of life.