Altered cerebral blood flow patterns associated with pathologic worry in the elderly

Background: Generalized anxiety disorder (GAD) is the most prevalent anxiety disorder among the elderly and has high functional and cognitive morbidity. However, late-life GAD is relatively understudied and its functional neuroanatomy is uncharted. Several imaging studies have suggested abnormalities in the cognitive control systems of emotion regulation in anxiety disorders in young adults. The aim of this study was to examine the neural correlates of emotion regulation in late-life GAD. Method: We compared 7 elderly GAD subjects and 10 elderly nonanxious comparison subjects using functional MRI. Regional cerebral blood flow (rCBF) was measured using pulsed arterial spin labeling perfusion MRI at rest and during an emotion regulation paradigm. Results: Relative to the rest condition, elderly nonanxious comparison subjects had increased rCBF during worry induction (WI) in the right insula, bilateral amygdala, and associative temporooccipital areas. Elderly GAD subjects had increased rCBF during WI in the associative temporooccipital areas, but not in the insula or the amygdala. During worry suppression (WS), elderly nonanxious comparison subjects had increased rCBF in the prefrontal cortex (PFC) and dorsal ACC. Elderly GAD subjects had no changes in rCBF during WS in the PFC. Conclusions: When attempting to regulate their emotional responses, elderly anxious subjects failed to activate prefrontal regions involved in the downregulation of negative emotions. These results, showing that elderly anxious subjects are not effectively engaging the PFC in suppressing worry, may be clinically relevant for developing personalized therapeutic strategies for the treatment of latelife GAD.