Adults undergoing bariatric surgery who are more physically active are less likely to be depressed, according to a new study, which found that being active for as little as eight minutes a day made a difference.
Obese adults are nearly twice as likely to have a major depressive disorder (13.3 percent) or anxiety disorder (19.6 percent) compared to the general population (7.2 and 10.2 percent), according to Wendy C. King, Ph.D., an epidemiologist at the University of Pittsburgh Graduate School of Public Health.
“Typically, clinical professionals manage their patients’ depression and anxiety with counseling and/or antidepressant or anti-anxiety medication,” she said. “Recent research has focused on physical activity as an alternative or adjunct treatment.”
Just one hour of moderate-intensity physical activity a week — or eight minutes a day — was associated with 92 percent lower odds of treatment for depression or anxiety among adults with severe obesity.
Similarly, just 4,750 steps a day — less than half the 10,000 steps recommended for a healthy adult — reduced the odds of depression or anxiety treatment by 81 percent.
“It could be that, in this population, important mental health benefits can be gained by simply not being sedentary,” said King, who also was the lead author of the study.
The researcher notes it is important to treat depression and anxiety prior to bariatric surgery. Preoperative depression and anxiety increase the risk of these conditions occurring after surgery — and have been shown to have a negative impact on long-term surgically induced weight loss.
As part of the Longitudinal Assessment of Bariatric Surgery-2, an observational study designed to assess the risks and benefits of bariatric surgery, King and her colleagues assessed participants’ physical activity for a week prior to undergoing bariatric surgery using a small electronic device worn above the ankle. Participants also completed surveys to assess mental health, symptoms of depression, and treatment for psychiatric and emotional problems, including depression and anxiety.
The study included 850 adults who were seeking bariatric surgery between 2006 and 2009 from one of 10 different hospitals throughout the United States.
Approximately one-third of the participants reported symptoms of depression, while two in five reported taking medication or receiving counseling for depression or anxiety.
The researchers noted that the link between physical activity and less depression was strongest when only moderate intensity physical activity was considered. However, the number of steps a person walked each day, no matter the pace, also was related.
“Another goal of this study was to determine physical activity thresholds that best differentiated mental health status,” said King. “We were surprised that the thresholds were really low.”
Because this was an observational, cross-sectional study — meaning patients’ regular physical activity and symptoms of depression were measured at the same time — the study could not prove that a patient’s physical activity influenced mental health.
“Results of the study are provocative, but we would need further research to verify that physical activity was responsible for lower levels of depressive symptoms in this patient population,” said study co-author Melissa A. Kalarchian, Ph.D., associate professor at Western Psychiatric Institute and Clinic, part of University of Pittsburgh Medical Center (UPMC). “Nonetheless, physical activity is a key component of behavioral weight management, and it is encouraging to consider that it may have a favorable impact on mental health as well.”
The study is published in the Journal of Psychosomatic Research.