Individuals in stable, long-term relationships have lower rates of depression and alcohol abuse.
For the purposes of the study, published in the British Journal of Psychiatry, researchers at the University of Otago surveyed 1,000 New Zealand residents.
Sixteen percent of those who were not in a relationship reported symptoms of depression, as compared to 23 percent of those in a short-term relationship of less than two years. However, the rate dipped to less than ten percent for those who had been in a relationship for two to four years, and only nine percent for those who were in a relationship of over five years.
The same trend was seen in alcohol dependence where the rate was 12 percent for those not in a relationship versus 13.5 percent of those in a short-term relationship. Again the rate dipped, down to four percent for those in a relationship of two to four years, and less than three percent for those who had been in a relationship of over five years.
"[I]t was the length of the relationship that had a positive effect on people’s mental health – and it did not matter if the couple was married or cohabiting. This is a contrast to previous studies, which have reported lower rates of mental health problems among people in legal marriages than in cohabiting relationships," said lead researcher Dr. Sheree Gibb.