Years of education may protect against dementia

Attaining a higher level of education is considered to be important in order to keep up good cognitive functioning in old age. Moreover, higher education also seems to decrease the risk to develop dementia. This is of high relevance in so far that dementia is a terminal disease characterized by a long degenerative progression with severe impairments in daily functioning. Despite a great amount of research emphasizing the relevance of education, it is not entirely clear how education protects cognitive functioning in old age and how much education is possibly ‘enough’. Scientific theories assume mainly two mechanisms: first, individuals with a high level of education may engage in a healthier lifestyle which protects them against dementia, and second, higher education builds up a so called ‘cognitive reserve’, which is the ability to keep up a good cognitive performance despite of brain pathology.

In order to get a better understanding of the role of education in the risk of developing dementia, we investigated in more detail how education – its concepts and its operationalization – impacts dementia risk. Individuals aged 75 years and older were recruited from the population registry office in the city of Leipzig, Germany. A total of 1,692 community-dwelling individuals (with 11.3% living in retirement homes) were identified. We observed the incidence of dementia in up to five follow-up assessments at an interval of 1.5 years and a final assessment after 15 years.

We analyzed the impact of education on dementia taking into account the effects of other important risk factors of dementia (age, gender, living situation, having had a stroke, heart attack diabetes, and depression). Our results demonstrated that – even when taking into account those other risk factors – every additional year of education significantly decreased the risk to develop dementia. Moreover, our results pointed out that ‘having completed more than ten years of education’ or a ‘tertiary level of education’ could be an important threshold for significantly reducing dementia risk. Complex classifications of education, which focused on occupational expertise and hierarchy of levels, did not seem to be relevant concerning dementia risk.

This therefore leads to an important assumption: the protective effect of education against dementia seems to be primarily driven by the duration of mental training – i.e. years of education. A possible explanation could be that at the age when we typically go to school, the brain is in a major developmental phase and therefore more school years could influence the development of the brain over a longer period. However, this raises the question whether the content of education matters and what skills and training may result in the strongest protection against dementia. It would be very interesting to learn in further studies what educational content – acquiring knowledge or rather the formation of skills in critical thinking, interpersonal communication, goal setting, or interpretation of information – matters most in reducing the risk of developing dementia.

Overall, our findings support the theoretical propositions that education builds up a so called ‘cognitive reserve’ and in this way keeps up a good cognitive performance despite of brain pathology, irrespective of socioeconomic implications. Further studies are necessary to investigate whether education lowers dementia risk in addition to socioeconomic factors such as income and social rank. If adverse socioeconomic conditions during childhood increase the risk of developing dementia, can higher education overcome this disadvantage? Are there perhaps interacting effects? Moreover, it is not yet entirely clear how education influences dementia risk on a biological level. Further research should explore the details of the biological pathways from education to dementia risk considering definitions and operationalization. Only by being aware of the applied definitions and operationalization will it be possible to gain a better understanding of the biological processes which actively influence dementia risk. Nonetheless, as attaining a higher level of education is important to keep up good cognitive functioning in old age, it ought to be a major public health goal. Developing countries are expected to suffer from an increased burden due to dementia in the near future and universal education as a public health goal could be an essential factor in alleviating burden on health care systems and the society.

Featured image: Old friends by stevepb. CC0 Public Domain via Pixabay.