Death Characteristics of Neurological Diseases in Inner Mongolia between 2008 and 2015

Background: There are no studies of death from neurological diseases found, however, neurological diseases were the leading cause of disability-adjusted life years in 2015 worldwide. Aim: The scientific aim of this study is to ana-lyze the death characteristics of neurological diseases in Inner Mongolia occurring between 2008 and 2015. Methods: The data collected from Death Registry System (DRS) were categorized by gender, ethnicity, age, and death location. The subjects were divided into age groups for every 10 years from the age of 20. Mortality and gender: age-specific mortality was calculated for every 100,000 people from 2008 to 2015. Results: We found that Alzheimer’s disease has the highest proportion which equated to over one-fifth of all neurological diseases. Males displayed a higher mortality rate than females in all neurological diseases. The neurological diseases mortality showed a total potential year of life lost (PYLL) of about 20,151 years, and it was 2.03 times higher for male than that for female. The average potential years of life lost (APYLL)


Introduction
Neurological diseases were the leading cause of disability-adjusted life years (DALYs) in 2015 worldwide although there have been no studies on death from neurological diseases [1]. Infections of the central nervous system (CNS) are frequent causes of neurological disorders [2], with viruses being among the most important causes of infectious neurologic illness worldwide [3]. Among the neurological disorders examined in the Global Burden of Disease, Injuries, and Risk Factors Study (GBD) 2015, extrapyramidal and movement disorders (mainly for Parkinson's disease) were the fastest growing in prevalence, disability, and the number of deaths [4]. World Health Organization (WHO) Study Group identified epilepsy to be a disorder that also has a high prevalence in developing countries and represents potentially severe consequences [5]. However, the burden of neurological disorders is more severe in low-and middle-income countries [1]. Previous work has revealed a significant correlation between motor disability and neurological diseases, and demonstrated that the severity of disability is higher in the elderly, people with less education, the self-employed, and widows [6].
Here we study the neurological diseases using data obtained from the Death Registry System (DRS) in Inner Mongolia. Our results show the characteristics of neurological diseases in Inner Mongolia and provide theoretical support for further studies.

Data Source
The data used in this study included the total population of Inner Mongolia be-

Statistical Analysis
The data collected from DRS were categorized by gender, ethnicity, age and death location. Ethnicity was divided into Mongolian, Han, and other nationality. The death location was divided into died at the hospital, died at home, died on the way to the hospital, and other location. Gender was divided into male and female. The subjects were divided into age groups for every 10          Note: n-is n-n + 9 years old group (e.g. 20-means 20 -29 years old group; 80-means ≥80 years old group).

Discussion
The present study provides a profile and determines the severity of diseases of the nervous system in Inner Mongolia between the years 2008 and 2015. We found that the mortality rates of neurological diseases fluctuated within a small range during the period of observation.
Nervous system diseases include a large number of disorders, and deaths from each individual disease are very small. We found that Alzheimer disease, epilepsy, sleep disorders and cerebral palsy account for the top four diseases which totals approximately half of all neurological diseases. Alzheimer's disease is the most prevalent disease with the highest mortality rate, more than twice as high as cerebral palsy which ranks as the second most prevalent neurological disorder in Inner Mongolia. People with cerebral palsy or epilepsy display a higher loss of life than those with Alzheimer's disease. This was due to the smaller age of onset and death in patients with either cerebral palsy or epilepsy, where Alzheimer's disease is more common in the elderly. The loss of life in cerebral palsy and epilepsy is more significant in assessing the residents' health.
Examining demographic characteristics, we found the mortality rate for neurological diseases to be generally higher in males than in females, and this may be related to differences in gene expression in the brains of males and females [8]. The average mortality for neurological diseases increased with age between 2008 and 2015, which conforms to the general pattern of diseases between these time periods. At the same time, as they grow older, they are likely to be accompanied by other diseases [9], which will also cause the rate of mortality to increase. Among all deaths in neurological diseases, the Han nationality has a much higher proportion than the Mongolian nationality, which was the second most represented. Most people die at home, which may be due to epilepsy is usually a sudden unexpected death [10], and Alzheimer disease, sleep disorders and cerebral palsy are chronic diseases [11] [12] [13], which pre-death symptoms, are not easily noticed, decreasing the likeliness of receiving timely medical treatment.

Conclusion
Alzheimer disease, epilepsy, sleep disorders and cerebral palsy are the top four most represented neurological diseases diagnosed throughout Inner Mongolia.
Alzheimer disease is the most serious disease with the highest mortality rate.
However, cerebral palsy and epilepsy showed the greatest loss in life expectancy.
Mortality of neurological diseases is generally higher in males than in females.
The average mortality for neurological diseases increased with age. Among all deaths in neurological diseases, the Han nationality displayed the highest proportion, and most people die at home.