Causes of Secondary Hyperhidrosis: Hyperhidrosis and Psychiatric Illness, Incl Social Anxiety Disorder
Several psychiatry texts state that patients with hyperhidrosis have excessive anxiety. This characterization is apparently based on case reports of successful decrease in symptoms through psychotherapy. Several small studies of the incidence of psychopathology in hyperhidrosis gave conflicting results and used “suboptimal measures of personality.” Forty-two patients scheduled for sympathectomy with primary hyperhidrosis were evaluated with two psychometric instruments, the Minnesota Multiphasic Personality Inventory (MMPI) and the State-Trait Anxiety Inventory (STAI). Scales of the MMPI measuring anxiety, depression, and conversion phenomena were within the normal range for 88% of patients, and 86% had normal scores on the STAI. The authors concluded that most patients with hyperhidrosis have no psychopathology and that symptoms of anxiety, depression, and social isolation in some of the patients were a reaction to the disorder rather than the cause.
Hyperhidrosis is a common symptom in social anxiety disorder (SAD), seen as part of increased physiologic arousal along with other symptoms such as blushing and tremor. A retrospective review of data from several studies of patients with social anxiety disorder determined that 25% to 32% of patients had symptoms of hyperhidrosis at baseline, depending on the assessment used. Patients with hyperhidrosis had more disability, fear, avoidance, and other arousal symptoms. Patients were treated with fluoxetine, clonazepam, gabapentin, cognitive behavior therapy, or placebo. Statistically significant reductions in hyperhidrosis were found only with fluoxetine using one assessment scale and with gabapentin using another. It was concluded that hyperhidrosis is common in patients with SAD, correlates with higher amounts of other physiologic symptoms, and has a variable response to psychopharmocologic therapy. Treating hyperhidrosis associated with social anxiety by endoscopic thoracic sympathectomy (ETS) in 51 patients, Teleranta reported a significant decrease in hyperhidrosis, blushing, tachycardia, tremor, and anxiety, leading to speculation that a central effect on anxiety occurs with alleviation of peripheral symptoms, possibly by feedback inhibition. A similar interruption of the cycle of anxiety-hyperhidrosis-anxiety may be obtained by using botulinum toxin A injections as adjunctive therapy in SAD patients.