Low IQ and poor cardiovascular fitness in teens increases risk of early-onset dementia

Harold Mandel's picture
Young teens staying in shape

Possibly being hit with the gradual worsening of cognitive abilities, or dementia, is a significant concern as we age. An increased understanding of this tragic condition often leads younger people to consider making a commitment to healthy lifestyles, such as daily exercise and good nutrition, to help avoid dementia. It appears these measures can be taken relatively early in life to attempt to avoid dementia from setting in as we age.

Patients suffering from early-onset dementia are being seen as occurring with increasing prevalence, reported the journal Brain. Good epidemiological studies dealing with this problem have been limited and there has been a lack of studies dealing with modifiable risk factors, such as physical fitness. Researchers decided to investigate the associations which exist between cardiovascular fitness in individuals and in combination with cognitive performance at age 18 and the risk of early-onset dementia and mild cognitive impairment later in life.

The researchers performed a population-based cohort study of over 1.1 million Swedish, 18-year-old, male conscripts, who took conscription exams between 1968 and 2005. These subjects were than followed for up to 42 years. During the conscription exams objective data on cardiovascular fitness and cognitive performance were collected. The research found that lower cardiovascular fitness and cognitive performance during early adulthood were associated with an increased risk of being hit with early-onset dementia and mild cognitive impairment later in life. Individuals with a combination of low cardiovascular fitness and low cognitive performance had the greatest risks.

Men who have poorer cardiovascular fitness and/or a lower IQ more at the age of 18 years are often found to suffer from dementia before the age of 60, reports the University of Gothenburg in Sweden, in a review of this research. Researchers at the Sahlgrenska Academy, University of Gothenburg, had previously analyzed Swedish men's conscription results and they were able to show an association between cardiovascular fitness as a teenager and health problems in later life. In their most recent study the Gothenburg research team observed that those individuals with poorer cardiovascular fitness and/or lower IQ during their teenage years more often suffered from early-onset dementia.


Sahlgrenska Academy researcher Jenny Nyberg, who headed the study, said, "Previous studies have shown the correlation between cardiovascular fitness and the risk of dementia in old age. Now, for the first time, we can show that the increased risk also applies to early-onset dementia and its precursors." The men who when conscripted had poorer cardiovascular fitness were found to be 2.5 times more likely to develop early-onset dementia in later life. There was a 4 times greater risk with a lower IQ. With a combination of both poor cardiovascular fitness and low IQ there was a 7 times greater risk of early-onset dementia.

Professor Georg Kuhn, senior author of the study, said, "We already knew that physical and cognitive exercise reduces the risk of neurological disease. Physical exercise increases nerve cell complexity and function and even generation of new nerve cells in the adult brain, which strengthens our mental and physiological functions." The bottom line is therefore that good cardiovascular fitness helps the brain become more resistant to damage and disease.

People who are hit with early-onset dementia are generally of working age and can have children
who are still living at home. Therefore, the consequences of this condition for both the sufferers and their families are often particularly tragic. Nevertheless, patients suffering from early-onset dementia are a relatively overlooked group. Nyberg points out that it is therefore important to initiate more research into how physical and mental exercise affect the prevalence of various types of dementia. It appears possible exercise can be used as both a prophylactic and as a treatment for people who are at risk for early-onset dementia.

It truly is very sad to see individuals hit with early-onset dementia. In this era of an increased potential for longer lives due to advances in the medical sciences this is very tragic. The well being of entire families are often put in jeopardy when early-onset dementia strikes, particularly when the added income from the person afflicted was needed.

It is therefore clearly advisable for physicians and public health officials to help educate the general public about how staying active, along with good nutrition, early in life, may help avoid this problem. It is also advisable for educators to join in with the sharing of knowledge about why it is so vitally important to keep your brain active at all times in your life. With these initiatives we should be able to lower rates of early-onset dementia.