Comparison between DSQIID total / sub-item scores and plasma p- tau elevation in adults with Down’s syndrome

Abstract Dementia screening questionnaire for individuals with intellectual disabilities (DSQIID) has been an appropriate screening tool for detecting dementia in Down’s syndrome. However, whether this questionnaire reflects the neuropsychiatric signs of Alzheimer’s disease in DS (DS-AD) still remains unknown. To address this issue, we compared plasma phosphorylated tau (P181tau: p-tau) of a representative AD biomarker with the total score and each sub-score of the DSQIID. DSQIID was completed in 43 of the 56 individuals with DS enrolled. DSQIID total scores tended to be positively associated with age, and some of the sub-scores were age-dependently elevated. DSQIID total scores and some sub-scores also positively correlated with plasma p-tau, while all those significant correlations disappeared after age-adjustment. Moreover, one sub-score appeared to have a significant negative correlation with plasma p-tau after age adjustment. DSQIID likely reflects age-associated behavioral changes in DS. The fact that their scores did not correlate with plasma p-tau after age-adjustment leads us to infer that there might be room for improvement in the DSQIID for detecting DS-AD.