Neurological conditions now have the highest rates of disability and ill health worldwide.
The Disparity
Although more than 80% of the neurological deaths and nervous system disorders occur in lower income countries, people living in high-income countries have about seventy times the number of neurological professionals per 100,000 people. Dr. Tedros Ghebreyesus, Director-General of WHO said that the study is an urgent message that brings awareness of the increasing number of individuals who are in need of treatment and rehabilitation. Dr. Ghebreyesus emphasizes the need for an improved understanding of brain health starting in early childhood.
The Top Ten
As of 2021 the ten neurological conditions causing the highest loss of health were stroke, brain injury, dementia, migraine, nerve damage, epilepsy, meningitis, autism spectrum disorder, neurological complications occurring from preterm birth, and cancers of the nervous system. There has been an increase in the number of people either living with or dying from neurological disorders since 1990. This is an indication that the statistics are mostly driven by people living longer and by demographic change.
Diabetic Neuropathy
Diabetic neuropathy is currently growing faster than the aforementioned neurological conditions. It has tripled worldwide since 1990 reaching a high of about 206 million cases by 2021. The increase correlates with the global increase in diabetes. On a positive note, since 1990, neurological health loss resulting from other conditions has decreased by over 25% due to various new methods of prevention, including research, vaccines and improved healthcare. The list includes rabies, tetanus, meningitis, stroke, neural tube defects, parasitic infection affecting the CNS, inflammation and injury to the brain.
Modifiable Risk Factors
The Lancet study also analyzed 20 risk factors believed to be modifiable in preventing such neurological conditions as dementia, stroke, and intellectual disability due to an unknown cause (idiopathic).
It is believed that if various risk factors are eliminated such as high systolic blood pressure and household air pollution, 84% of disability adjusted light years (DALY) could be prevented. DALY is a measure of the number of years that are lost due to premature mortality.
The researchers reported that as we are aware, preventing lead exposure also reduces intellectual disability by a total 63.1%. Smoking is reported to have a significant effect on strokes, multiple sclerosis and risk of dementia.
Over 3.4 billion people, or 43 percent of the world’s population, reported a neurological condition in 2021. The U.S. IHME, which is recognized as the global reference for health statistics, conducted the analysis. The lead author at IHME was Jaimie Steinmetz, who said that issues with the nervous system are now the leading cause of disease burden in the world, having risen 59% within the past three decades. The obvious factor would be that the world’s population was aging and rapidly expanding.
In 2021 over 11 million people had died as a result of the 37 neurological conditions set out in the study. The data was used to estimate the number of healthy life years lost from each condition. It is called disability-adjusted life years (DALYs). Stroke, which had been previously counted as a heart disease, was listed as the most prevalent neurological condition analyzed.
The second disorder was a type of brain damage known as neonatal encephalopathy, followed by migraine, dementia (including Alzheimer’s disease), nerve damage resulting from diabetes, meningitis, and lastly, epilepsy. The list also included cognitive impairment from COVID-19. The WHO reclassified stroke, putting it into the neurological category, thereby causing conditions affecting the nervous system to outnumber cardiovascular disease.
Some factors that create a huge number of lost healthy years are conditions that effect children under the age of five such as birth trauma that leads to asphyxia, meningitis, or neonatal encephalopathy.
These conditions occur at such a young age that it results in a large contribution to years of life lost.
Currently there is no cure for most of these disorders.
The researchers can only suggest that attempts are made to reduce the risk of high blood pressure as well as diabetes and alcohol consumption. They remind the public that these disorders are disproportionately affecting poorer countries. That the neurological burden is growing rapidly and will assert even more pressure on health systems.
