Social Support and Cognitive Impairment: Results from a Portuguese 4-Year Prospective Study

(1) Background: In an ageing society, social relationships may benefit cognitive performance with an impact on the health of older people. This study aims to estimate the effect of different social support sources on the risk of cognitive impairment in a sample of older Portuguese people. (2) Methods: From the Portuguese EpiPorto cohort study, we followed a sample of participants with 60 to 85 years (N = 656) between 2009 and 2015 (4.63 mean years of follow-up). The participants' perception of social support from family, friends and significant others was evaluated. Cox's regression models were used to investigate the association between this and sociodemographic variables. (3) Results: It was found that social support from friends reduces the risk of cognitive impairment. Men, participants aged 60 to 64 and those not married have a lower risk of cognitive impairment after adjusting for other variables. Participants between 80 and 85 years old (p = 0.021), those with less than four years of education (p < 0.001), and those with cognitive impairment (p = 0.007) have perception of less social support from friends. (4) Conclusions: A social support network from friends reduces the risk of cognitive impairment for older people.