title: Associations between social networks, social contacts, and cognitive function among Chinese nonagenarians/centenarians.
abstract: OBJECTIVE
  To explore the associations between social networks, social contacts, and cognitive impairment in the very elderly aged 90-108 years.
  
  
  METHODS
  Data were from subjects of the Project of Longevity and Ageing in Dujiangyan, China. The socio-demographic, social networks, and social contacts data were collected and cognitive function was assessed in all subjects using the Mini-Mental State Examination (MMSE).
  
  
  RESULTS
  764 Chinese nonagenarians and centenarians (67.41% women, mean age 93.47 years) were included. The mean MMSE score was 14.99 ± 5.93). The prevalence of cognitive impairment was 64.53%. The mean social contact score was 4.37 ± 1.86. There were significantly different cognitive function scores among individuals with different marital status, number of close friends, and different social contact levels (all P<0.05). Spearman rank correlation analysis showed that number of close friends and social contact scores were significantly positively but single status was significantly negatively correlated with the MMSE scores (all P<0.05). Multiple logistic regression analysis showed that there were associations between single status, no close friend, and low level of social contact with cognitive impairment (all P<0.05), but not other social network variables.
  
  
  CONCLUSIONS
  Single status, no close friend, and low level of social contact were associated with increased risk of cognitive impairment in Chinese nonagenarians and centenarians. Our finding might add new information for social networks, social contacts, and cognitive research in the elderly.
authors: Department of Geriatrics, West China Hospital, Sichuan University, Chengdu, China; Department of Geriatrics, Second People's Hospital of Chengdu, Chengdu, China.
authors: Binyou
authors: B
authors: Wang
authors: Department of Respiratory Diseases, Third People's Hospital of Chengdu, Chengdu, China.
authors: Ping
authors: P
authors: He
authors: Department of Geriatrics, West China Hospital, Sichuan University, Chengdu, China; The Center of Coordination and Innovation for Aging Care and Health Promotion of Sichuan, Chengdu, China. Electronic address: birongdong@163.com.
authors: Birong
authors: B
authors: Dong
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000523:psychology*; D002681:China / Q000453:epidemiology; D003071:Cognition / Q000502:physiology*; D003072:Cognition Disorders / Q000453:epidemiology* / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008609:Mental Status Schedule; D015995:Prevalence; D012919:Social Behavior; D012944:Social Support
keywords: Cognitive impairment; Mini-Mental State Examination; Nonagenarians and centenarians; Social contacts; Social networks