The trend analysis of neurological disorders as major causes of death and disability according to human development, 1990-2019

This study aims to assess the trends in the incidence rate of neurological disorders in developed and developing countries worldwide during 1990-2019. The age-standardized incidence rate (per 100000 persons) of neurological disorders was the primary outcome, extracted from the Global Burden of Disease database for 189 countries and territories from 1990 to 2019. Using the Human Development Index (HDI), countries were classified into developed (HDI >= 0.7) and developing (HDI < 0.7) groups. Longitudinal analysis was performed using the Latent Growth Model (LGM) to assess the change in the incidence rate of neurological disorders over time in these groups. In developed countries, the most increasing rate is related to depressive disorders, with a rising rate of 40.15 in 100000 every five years (p = 0.001). Alzheimer's and dementia, Parkinson and multiple sclerosis are in the next rank, with increasing rates of 8.77, 1.24, and .02, respectively (all p < 0.001). Over time, the significant decreasing trend has been determined related to conducting disorder, attention-deficit and hyperactivity, meningitis, anxiety, and eating disorders, with the rates of - 13.92, - 4.96, - 2.7, - 1.6, and - 1.44, respectively (all p < 0.05). In developing countries, meningitis, conduct disorder, attention-deficit and hyperactivity, stroke, and autism spectrum showed a significant decreasing trend over time, with rates of - 15.45, - 5.84, - 2.56, - 1.86, and - 1.07, respectively (all p < 0.05). Headache disorder has the most increasing rate of 79.5, following depressive (rate 35.32), substance use (rate 14.99), anxiety (rate 7.18), and eating (rate 3.4) disorders. Also, Alzheimer's and dementia, bipolar disorder, schizophrenia, Parkinson's, brain and central nervous system cancer, and multiple sclerosis are in the next rank and had significant increasing trends (all p < 0.05). Given the high economic and social burden of neurological disorders, the rate of these diseases in most countries does not seem to have dropped remarkably. The heterogeneous incidence rate in some world countries seems to be due to underestimating and gaps in epidemiological information. It is necessary to provide exact registry systems for health policies, especially in developing countries.