New York, Sep 26 (IANS): Most obese people feel better after weight-loss surgery but unfortunately, this is not true for some, says a study.

Symptoms of depression worsened for many patients when the levels of depression in patients were measured six to 12 months after they have had bariatric surgery, the findings showed.

For the study, the researchers set out to investigate if depressive symptoms increase markedly or not at all, after post-surgery.

The study involved 107 patients with extreme obesity.

Consistent with previous research, the researchers observed that most people who had undergone this procedure were in much better spirits.

However, in some cases negative mood changes started to creep in between six and 12 months after the operation, with 3.7 percent of patients reporting that they felt discernibly more depressed 12 months post-surgery.

Between six and 12 months after the operation, however, even more patients (13.1 percent) reported increases in depressive symptoms.

These changes went hand-in-hand with significantly lower levels of self-esteem and social functioning.

“The majority of patients whose mood had worsened discernibly experienced these mood changes between six and 12 months post-surgery, suggesting this may be a critical period for early detection and intervention, as needed,” explained Valentina Ivezaj from Yale University School of Medicine in the US.

“The increases in symptoms of depression are also notable given that they were associated with other difficulties including lower self-esteem and social functioning,” Carlos Grilo from Yale University School of Medicine in the US added.

The study appeared in the journal Obesity Surgery.