TY - JOUR AU - Pushpanathan, Maria AU - Loftus, Andrea M AU - Gasson, Natalie AU - Thomas, Meghan G AU - Bucks, Romola S PY - 2019 DA - 2019/09/23 TI - Sleep Symptoms Differentially Predict Cognition in Younger and Older-Onset Parkinson's Disease JO - OBM Geriatrics SP - 075 VL - 03 IS - 03 AB - Abstract Background: Both disrupted sleep and cognitive impairment are frequent in Parkinson’s disease (PD), but the evidence for a relationship between self-reported sleep disturbance and cognitive symptoms has been equivocal. If sleep symptoms differentially predict cognition in different subtypes, effects may be obscured in a general PD sample. Objective: First, to determine whether the associations between participant and disease variables, sleep symptoms and cognitive performance vary by subtype (younger and older-onset); then to establish whether these effects remain when the sample is reanalysed as a whole. Methods: Multi-group path analyses were used to model the relationships between participant and PD variables; factor scores derived from our bifactor analysis of the Parkinson's Disease Sleep Scale-Revised; and, measures of memory and executive function. Path analyses were replicated as single group analyses. Results: Increased general sleep disturbance predicted better verbal recall in younger-onset PD and poorer visual episodic memory in older-onset PD. Increased insomnia scores predicted better verbal recognition memory in younger-onset PD, better verbal fluency in both groups and poorer spatial working memory (SWM) in older-onset PD. Higher OSA and RBD scores predicted poorer spatial recognition memory and spatial working memory in younger-onset PD, but did not predict cognition in older-onset PD. Many regression coefficients were weakened or reduced to non-significance in the single-sample models. Conclusions: The relationships between participant variables, sleep, and cognition were markedly different in younger and older-onset PD. The influence of sex and premorbid IQ as moderating variables warrant further investigation. SN - 2638-1311 UR - https://doi.org/10.21926/obm.geriatr.1903075 DO - 10.21926/obm.geriatr.1903075 ID - Pushpanathan2019 ER -