A follow-up study of painful diabetic neuropathy: physical and psychological aspects.

Twenty-one patients with painful diabetic neuropathy were followed up for about 18 months by means of physical and psychological tests. Patients with painful diabetic neuropathy had significantly more neurotic, anxious and depressive traits than those with non-painful diabetic neuropathy. During the course of the study, 17 patients out of 21 were found to be relieved of their neuropathic symptoms with improved blood glucose control and medications. However, despite this improvement, diabetic retinopathy and nephropathy of the patients deteriorated. Patients with improved neuropathy had gained body weight, with a concomitant relief of depression, nervous tendency and anxiety. However, lack of extroversion was not changed at all. Patients with painful diabetic neuropathy were significantly less extroversive than those with non-painful diabetic neuropathy, even when their neuropathic symptoms might have improved. This study shows that although nervousness, anxiety and depressive tendencies may be secondary to the symptoms of painful diabetic neuropathy, lack of extroversion can be a primary characteristic trait which may easily induce painful diabetic neuropathy.