The study included 94 women and 13 men who were asked about their mood before having weight-loss surgery, and again six and 12 months after the procedure.
Most people had a normal or improved mood after weight-loss surgery, but some said they had negative mood changes. At 12 months after the operation, almost 4 percent of patients said they felt more depressed than before the procedure, the investigators found.
Even more patients (about 13 percent) reported increases in depressive symptoms between six and 12 months after weight-loss surgery, according to the study published recently in the journal Obesity Surgery.
There was also a significant association between negative mood changes and lower levels of self-esteem and social functioning, the study authors reported.
The findings suggest that between six and 12 months after weight-loss surgery may be a critical period for early detection and treatment of depression in patients, Valentina Ivezaj and Carlos Grilo of Yale University School of Medicine, said in a journal news release.
Ivezaj and Grilo pointed out that the levels of symptoms reported were those of a mild mood disturbance. They added it would be important to see if these symptoms worsen past the 12-month time period studied.
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