title: Stage-Specific Relationship between Frailty and Cognitive Impairment in a Specialist Memory Clinic Setting.
abstract: BACKGROUND
  It is unclear if the complex relationship between physical frailty and cognition varies across the severity of cognitive impairment.
  
  
  OBJECTIVE
  We therefore aimed to explore if there are stage-specific differences in the relationship between frailty and cognitive impairment.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  A specialist Memory Clinic setting.
  
  
  METHODS
  Mild cognitive impairment (MCI) and mild-moderate Alzheimer's disease (AD) community-dwelling subjects.
  
  
  METHODS
  We obtained data on demographics, multimorbidity, cognition-related measures, nutrition, neuroimaging measures, muscle mass, Vitamin D level, apolipoprotein - e (APOE) status and physical performance measures. Frailty measures of gait speed, hand grip strength, question on exhausation and weight loss, classified subjects according to the Buchmann criteria into non-frail and frail categories.
  
  
  RESULTS
  Forty-five MCI, 64 mild AD and 13 moderate AD subjects (total n=122) were studied. The prevalence of frailty for MCI, mild AD and moderate AD was 35.6%, 21.9% and 46.2% respectively, indicating a u-shaped trend. Significant differences were noted in fatigue, grip strength and gait speed frailty sub-items. Significant correlation of frailty with cognition were noted in mild-moderate AD (Spearman's coefficient 0.26, p<0.05) but not in MCI (0.01, p=0.6). No other differences in multimorbidity, Vitamin D, APOE, nutritional measures, white matter lesions were observed. Sarcopenia interestingly had an inverse stage-specific relationship unlike frailty.
  
  
  CONCLUSIONS
  Our results suggest a U-shaped relationship between frailty and cognition, characterized by initial dissociation with cognitive impairment and subsequent convergence at later stages. Future studies incorporating immune markers and endocrine pathways with longitudinal follow-up could potentially elucidate intermediary mechanisms in the frailty cascade.
authors.affiliation: Dr Chong Mei Sian, Senior Consultant, Institute of Geriatrics and Active Ageing, Tan Tock Seng Hospital, 11 Jalan Tan Tock Seng, S308433, Singapore, Email address: Mei_Sian_Chong@ttsh.com.sg, Telephone: (65)63596251, Fax number: (65)63596294.
authors.forename: M S
authors.initials: MS
authors.lastname: Chong
authors.forename: L
authors.initials: L
authors.lastname: Tay
authors.forename: M
authors.initials: M
authors.lastname: Chan
authors.forename: W S
authors.initials: WS
authors.lastname: Lim
authors.forename: R
authors.initials: R
authors.lastname: Ye
authors.forename: W C
authors.initials: WC
authors.lastname: Wong
authors.forename: J P
authors.initials: JP
authors.lastname: Lim
authors.forename: E K
authors.initials: EK
authors.lastname: Tan
authors.forename: Y Y
authors.initials: YY
authors.lastname: Ding