TABLE 1.
Demographics and Clinical Characteristics of the 13 Patients With Psychogenic Tremor
| Sex | AAO | DD | Acute Onset | Spontaneous Remissions | Placebo Response | Remission with Psychotherapy | Absent When Unobserved | Underlying Psychopathology | FH | Other Somatizations | Tremor Distribution | Distract ability* | Entrain ment | Unusual Variability | Coactiva tion | Other Features | Level** | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| P1 | F | 53 | 1 | Y | N | Y | N | N | MLE | N | N | RA, LA | Y | N | Y | Y | Uses wheelchair, fatigue | A |
| P2 | M | 68 | 3 | Y | N | Y | N | N | N | N | N | RA, LA | Y | N | N | N | N | A |
| P3 | F | 22 | 8 | Y | N | Y | N | N | N | N | DA, UP | RA, LA, LL | N | N | Y | N | Unusual parkinson-like gait | A |
| P4 | F | 17 | 2 | N | N | NA | N | N | ED | N | N | H, RA, LA | N | N | N | Y | N | B |
| P5 | F | 48 | 6 | Y | N | Y | N | N | D | N | N | RA, LA, RL, LL | N | N | Y | Y | Unusual gait | A |
| P6 | M | 60 | 4 | Y | N | Y | N | N | D | N | N | RA, RL | Y | Y | N | Y | Unusual gait | A |
| P7 | M | 39 | 7 | N | N | Y | N | N | N | N | N | H, RA | Y | N | N | N | Unusual gait and slowness | A |
| P8 | F | 33 | 3 | N | N | Y | N | N | ED, S | N | N | RA, LA | N | N | Y | N | N | A |
| P9 | F | 18 | 11 | Y | N | Y | N | N | D | N | UP, UV | RA, LA, RL | N | N | Y | Y | N | A |
| P10 | M | 34 | 20 | N | Y | NA | N | N | N | N | N | RA, LA | N | N | Y | Y | Unsteadiness | B |
| P11 | F | 35 | 17 | Y | N | Y | N | N | D | N | UP, UB | RA, LA, RL, LL | N | N | Y | Y | Unusual gait, uses wheelchair | A |
| P12 | M | 41 | 4 | Y | N | NA | N | N | N | N | N | LA | N | N | Y | Y | Give-way weakness | B |
| P13 | M | 39 | 18 | Y | N | Y | N | N | N | N | N | LA | Y | N | Y | Y | Position-specific tremor | A |
P1-13, psychogenic tremor patients.
Distractibility (with counting backward, arithmetics, performing a tapping sequence with the other hand, and recognizing a letter being written by the examiner on the patient's back). AAO, age at onset in years; DD, disease duration in years; Y, yes; N, no; NA, not applicable; placebo response, a nonphysiological (placebo) response to botulinum toxin injections, defined as tremor cessation immediately after injections lasting more than 1 hour; MLE, major life event before tremor onset, such as sexual abuse; D, depression; ED, eating disorder; S, history of self-harm; AD, anxiety disorder; FH, positive family history for tremor or another movement disorder in a first-degree relative; DA, Dermatitis artefacta; UP, medically unexplained pain disorder; UV, medically unexplained vomiting; UB, medically unexplained bladder dysfunction requiring self-catheterization; H, head; RA, right arm; LA, left arm; RL, right leg; LL, left leg; T, trunk.
Level of diagnostic certainty of psychogenic tremor according to current clinical diagnostic criteria (A: documented; B: clinically established; C: probable; D: possible).2