Imaging Predictors of Treatment Response in Depression

Altered activity of limbic structures has repeatedly been demonstrated in depression. To determine whether limbic activity could predict response to specific antidepressant therapies, investigators obtained baseline positron emission tomography (PET) scans of 82 patients with uncomplicated, nonpsychotic, mild-to-moderate major depression (mean Hamilton Rating Scale for Depression [HRSD] score, 19). Patients were then randomized to 12-week treatment with escitalopram (10–20 mg/day) or cognitive-behavior therapy (CBT).

Of 65 completers, 38 patients had both adequate PET scans and either remission (HRSD, ≤7) or poor response (≤30% decrease in HRSD). Among the 38 patients, hypermetabolism in the right anterior insula compared with whole brain me…