Retrospective birth dating of cells in humans
Although decreased volumes of the striatum and cerebral white matter could represent early degenerative changes, the finding of an enlarged cortex suggested that developmental pathology occurs in HD. (2007) compared psychiatric manifestations among 29 HD mutation carriers with no clinical symptoms, 20 HD mutation carriers with mild motor symptoms, 34 manifesting HD patients, and 171 nonmutation controls.The mild motor symptoms group and the manifesting HD group showed significantly higher scores for obsessive-compulsive behavior, interpersonal sensitivity, anxiety, paranoia, and psychoticism compared to the nonmutation control group.Dysphagia and dysarthria appeared to be caused by a 'cough-like movement' just before or during speaking or swallowing.Because the 'cough-like movement' progressed for 3 years and was eventually suppressed with disappearance of dysphagia after administration of haloperidol, this symptom was thought to be due to HD. (2006) studied the brain structure of 24 preclinical HD patients as measured by brain MRI and compared them to 24 healthy control subjects matched by age and gender.For example, gene carriers lost to follow-up, those deceased before onset of disease, and those who had not yet manifested the disease at the time of data collection were excluded from the observed distribution of age at onset.Shiwach (1994) performed a retrospective study of 110 patients with Huntington disease in 30 families.However, the whole group of heterozygous and homozygous normal at-risk individuals showed a significantly greater number of psychiatric episodes than did their 43 spouses, suggesting stress from the uncertainty associated with belonging to a family segregating this disorder. (1995) performed extensive neuropsychologic evaluations on 8 genotype-positive individuals comparing them to 8 genotype-negative individuals from families with Huntington disease.They found no significant differences between these 2 groups, casting further doubt on earlier reports that suggested cognitive impairments are premonitory signs of the classical neurologic syndrome of Huntington disease. (1995) performed a double-blind study on 33 persons at risk for HD who had applied for genetic testing.
In normal individuals, the range of repeat numbers is 9 to 36.
They found that psychomotor skills showed the most significant consistent decline among cognitive functions assessed. (1996) described an unusual HD family in which all 4 affected members presented first with a severe psychiatric syndrome which in 3 cases was schizophreniform in nature.
Two other living members with no apparent signs of motor disorder had received psychiatric treatment, 1 for schizophrenia. (1999) described a case of late-onset Huntington disease with the first symptom of dysphagia.
The age at onset was highly variable: some showed signs in the first decade and some not until over 60 years of age.
Shiwach and Norbury (1994) clashed with the conventional wisdom that psychiatric symptoms are a frequent presentation of Huntington disease before the development of neurologic symptoms.