<unk>  is estimated to have a prevalence of about one per million. Underdiagnosis and misdiagnosis hinder epidemiological information about the condition and may have led to its prevalence being underestimated. In the United Kingdom, 119 cases were identified between 2000 and 2005. It does not predominantly occur in any racial or ethnic group. The age of onset varies from about 30 to 60, and it most frequently occurs in people in their 40s. Five to ten percent of patients with<unk>  have the paraneoplastic variant of the condition. In one group of 127 patients, only 11 of them had paraneoplastic symptoms. About 35 percent of<unk>  patients have type I diabetes.
Stiff-person syndrome
Parkinson-plus syndrome
Dejerine–Roussy syndrome
Mauriac syndrome
Stiff skin syndrome
Dopamine-responsive dystonia
Huntington's disease-like syndrome
Benign fasciculation syndrome