Living alone may be bad for your health.

Danish researchers began studying 3,346 men, average age 63, in 1985, tracking their health for 32 years. Over the period, 89 percent of the men died, 39 percent from cardiovascular diseases.

The analysis, in European Heart Journal Quality of Care & Clinical Outcomes, controlled for a variety of health and behavioral characteristics, including body mass index, smoking, blood pressure, diabetes and blood lipid levels. Still, men who lived alone had a 23 percent increased risk for dying prematurely from any cause and a 36 percent increased risk for cardiovascular death.

Living alone was not associated with dying prematurely for those in the highest socioeconomic group — the 19 percent of study participants who had a university degree or worked in an executive position. But for the rest, the lower the socioeconomic status, the higher the risk for death. The authors emphasize that the remaining 81 percent of the population was not deprived or living in poverty, but consisted mainly of middle-class and skilled and unskilled workers.

“It’s paradoxical that the more we live in concentrated populations in big cities, the more people are living alone” said the lead author, Dr. Magnus T. Jensen, a researcher at Copenhagen University Hospital. “Social isolation is a global problem and won’t be solved on an individual level. Structurally, how can we design cities so that they are built for social interaction?”