Middle-aged men with chronically low serum cholesterol levels are more likely than other men to show symptoms of severe depression, concludes a new study conducted in The Netherlands.
The research subjects were randomly selected from a group of more than 30,300 men aged 40 to 70 years who had participated in a cholesterol screening survey in the Rotterdam metropolitan area. Three years after the initial screening, more than 700 of the men were invited to have their cholesterol levels rechecked.
One hundred and thirty of the men whose cholesterol levels had remained low, less than, or equal to 4.5 millimoles per liter (mmol/liter), were matched by age and socioeconomic background to 130 men whose cholesterol levels had remained between 6 and 7 mmol/liter. The study participants were not taking antidiabetic medication or cholesterol-lowering drugs and did not have kidney disease, thyroid disease, or cancer.
In addition to having their cholesterol levels checked, all of the study participants completed a questionnaire about medication use, chronic diseases, and diet, as well as psychological questionnaires to identify depressive symptoms, anger, hostility, and impulsivity.
The researchers found that the relative risk of having severe depressive symptoms was four to seven times higher in the men with chronically low cholesterol levels compared to the reference group. Recent weight loss and lower caloric intake also were associated with a higher risk of depressive symptoms. The researchers found no clear difference in the two groups' anger, hostility, or impulsivity, however. The research appears in the current issue of Psychosomatic Medicine.
"Studies looking at the relationship between cholesterol level and depressive symptoms are scarce," said study co-author Diederick E. Grobbee, MD, PhD, chair of the Julius Center for Patient Oriented Research, University Medical Center, Utrecht, The Netherlands.
"Because there has been so little research in this arena, the reasons why low cholesterol influences the occurrence of depressive symptoms are unknown," said Grobbee. "This study provides further evidence that there is a relationship and reinforces the need to look at the reasons for the relationship."
The research was supported by the Netherlands Prevention Fund and the Rotterdam Medical Research Foundation.
Psychosomatic Medicine, published bimonthly, is the official peer-reviewed journal of the American Psychosomatic Society. For information about the journal, contact Joel E. Dimsdale, MD, at (619) 543-5468.
Posted by the Center for the Advancement of Health < http://www.cfah.org . For information about the Center, call Petrina Chong, < pchong@cfah.org > (202) 387-2829.
Journal
Psychosomatic Medicine