Baseline saliva level of 3-methoxy-4-hydroxyphenylglycole (MHPG) associates with a consequent cognitive decline in non-demented elderly subjects: Three-years follow-up study

The aim of the study was to explore the relation between saliva level of 3-methoxy-4-hydroxy-phenylglycol (MHPG) and a later cognitive decline in non-demented elderly subjects. We have reported that sMHPG in 214 elderly subjects living in the community (age 74.5 ± 5.9 years) was associated with scores on the Mini-Mental State Examination (MMSE) and the Frontal Assessment Battery (FAB) in 2004 to 2006 (Time A). The same cohort underwent these cognitive tests again from 2007 to 2009 (Time B). The cognitive function of the 147 of 214 subjects could be reassessed by the same cognitive tests. The score on the FAB, but not the MMSE, was significantly reduced at Time B (14.6 ± 2.6) compared with that of Time A (15.2 ± 1.9). There was a significant negative correlation between the baseline sMHPG and the changes in the FAB score subtracted from Time B to Time A or the scores on the FAB at Time B in men, but not at Time A. These correlations were not found in women. These data indicate that high sMHPG might be associated with subsequent cognitive decline assessed by the FAB in non-demented elderly men living in the community.