People’s cognitive abilities begin to decline after the age of 45 years, long before the age of 60 years, once regarded as the threshold beyond which cognitive decline begins, say authors of a study by INSERM (Institut National de la Santé et de la Recherche Médicale – National Institute of Health and Medical Research, a public institution in France) and University College of London, informs AFP. “Our ability to think and understand begins to decline from the age of 45 years”, said researchers from the National Institute de la Santé and Recherche Medicale in a statement accompanying an article about this study, published Friday in the British Medical Journal (BMJ).
Tests of memory, vocabulary, reasoning and oral expression were performed on 5,198 men and 2,192 women aged between 45 and 70 years in a large study – Whitehall II – medical monitoring – of 10 years, based on individual tests. “The results show that cognitive performance (except for vocabulary tests) decreases with age, more quickly as people get older”, said scientists at INSERM. During a period of 10 years, reasoning performance declined by 3.6% for men in the age group 45-49 years and 9.6% for the age group 65-70 years. In women, the decrease is the same (-3.6%) for the first age group and less pronounced (-7.4%) for the second age groups.
Although it is already known that cognitive performance decreases with age, the time of commencement of this decline has always been a matter of controversy among researchers. Until recently, the authors of recent studies strongly stated that cognitive decline may not begin before the age of 60 years. The findings of this study is important because the drugs administered for Alzheimer’s disease, for example, would work better when people start to experience mental problems. It is believed that factors such as high blood pressure, high cholesterol, obesity and smoking would have an influence on the development of Alzheimer’s due to their effect on brain cells and blood vessel in the brain.
