Accelerate aging is a worldwide problem. In underdeveloped countries, it is occurring without adequate planning and is attributed due to falling mortality and fertility, which contributed to increase life expectancy. However, aging was not accompanied by improvement in living conditions and health assistance. Poor sanitation and diet, low incomes and education levels contributed to increasing the prevalence of chronic diseases in elderly.

Data obtained in other countries could not represent the national population; objective was to describe a Brazilian frailty elderly sample.

Determine cognitive impairment prevalence in Brazilian frailty elderly.

1952 frailty elderly were analyzed. Social data, tobacco and alcohol consumption were verified and mini-mental state examination was applied from February to August in 2010.

Female elderly was predominant (68.8%). They were almost married (47.5%), followed by widow (37%), single (8.1%), divorced (7.4%). White people were predominant (69.2%); black (14.6%) and brown (16.2%) were presented at the same proportion. 823 frailty elderly (64.9%) studied until 4 years; 7.7% studied between 4–8 years; 1.9% went to college and 25.6% were illiterate. Only 10.6% were smokers and 2.8% drank alcohol. The majority (79.4%) were younger than 80 years-old. Cognitive impairment prevalence were 17.2% in illiterate; 15.2% in elderly who studied until 4 years and lower, 5.3%, in the group who studied between 4–8 years.

The prevalence of cognitive impairment was dependent on years of study and we presented data obtained in a Brazilian sample. These data can be used to compare cognitive impairment in different countries.