Research suggests that older adults with symptoms of depression are more likely to gain abdominal fat (compared to other types of fat) over a five-year period. In light of the fact that about 10 percent to 15 percent of older adults have symptoms of depression, this could represent a serious health risk. Depression has been associated with weight gain and the onset of diabetes, cardiovascular disease, and cardiac mortality.
According to the researchers of this study, published in the December issue of Archives of General Psychiatry, there research helps explain why depression is often followed by diabetes and/or cardiovascular disease.
The head researcher, Nicole Vogelzangs, and her colleagues studied 2,088 adults age 70 to 79 years. Participants were screened for depression at the beginning of the study and their overall and abdominal obesity was recorded then and measured again after five years.
Measures of overall obesity included body mass index and body fat percentage. Abdominal obesity was assessed using waist circumference, sagittal diameter (distance between the back and the highest point of the abdomen) and visceral fat (fat between the internal organs) measured by computed tomography.
At the beginning of the study, 4 percent of participants had some level of depression. At the five yeasr mar, depression was associated with an increase in sagittal diameter and visceral fat over five years.
According to the researchers, “Such an association was not found for an increase in overall obesity and also appeared to be independent of changes in overall obesity, suggesting that depressive symptoms are rather specifically associated with fat gain in the visceral region,”
The researchers noted that there are several mechanisms by which depression might increase abdominal fat. Chronic stress and depression can activate certain brain areas and lead to increased levels of the hormone cortisol, which promotes the accumulation of abdominal fat.
Additionally, individuals with depression may have unhealthier lifestyles, including a poor diet, which can interact with other physiological factors to produce an increase in abdominal obesity.
The researchers concluded that, “Our longitudinal results suggest that clinically relevant depressive symptoms give rise to an increase in abdominal obesity, in particular visceral fat, which seems to be stronger than and independent of overall obesity.”