CSF monoamine metabolites in old age dementias

Cerebrospinal Fluid (CSF) levels of the main metabolites of monoamines (HMPG, 5-HIAA, and HVA) were measured in patients with early onset (AD) and late-onset (SDAT) Alzheimer’s disease, vascular dementia (VD), and elderly controls. Psychobehavioral assessment was carried out by means of MMSE and GBS. Mean HMPG levels did not differ from controls; 5-HIAA was lower in VD when compared to both controls and SDAT. HVA was decreased in AD, SDAT, and VD with respect to controls. Significant correlations between HVA and psychobehavioral parameters were observed in SDAT and VD groups, whereas no relationship was documented in AD. The SDAT group was divided in SDAT-A (age at onset: >65≤80 yr) and SDAT-B (age at onset: >80 yr). SDAT-A had significantly lower CSF HVA values than SDAT-B (165±64 vs 235.7±85). SDAT-B HVA levels were similar to those observed in controls. Correlation analysis between HVA and neuropsychological variables was significant in SDAT-A, but not in SDAT-B. These results might support the evidence of SDAT heterogeneity.