RESUMO
OBJECTIVE: In 2000, the global density of neurosurgeons was estimated at 1 per 230,000 population, which remains the most recent estimate of the global neurosurgeon workforce density. In 2004, the World Health Organization (WHO) estimated that there were 33,193 neurosurgeons worldwide, including trainees. There have been no updates to this estimate in the past decade. Moreover, only WHO region-level granularity regarding neurosurgeon distribution exists; country-level estimates are limited. The neurosurgery workforce is a crucial component to meeting the growing burden of neurosurgical diseases, which not only represent high absolute incidences and prevalences, but also represent correspondingly high disability-adjusted life years affecting hundreds of millions of people worldwide. Combining the lack of knowledge about the availability of the neurosurgical workforce and the increasing demand for neurosurgical services underscores the need for a system of neurosurgical workforce density surveillance. METHODS: This study involved 3 key steps: 1) global survey/literature review to obtain the number of working neurosurgeons per WHO-recognized country, 2) regression to interpolate any missing data, and 3) calculation of workforce densities and comparison to available historical data by WHO region. RESULTS: Data for 198 countries were collected (158) or interpolated (40). The global total number of neurosurgeons was estimated at 49,940. Overall, neurosurgeon density ranged from 0 to 58.95 (standardized to per 1,000,000 population) with a median of 3.56 (IQR 0.29-8.26). Thirty-three countries were found to have no neurosurgeons (zero). The highest density, 58.95, was in Japan, where 7495 neurosurgeons are taking care of a population of 127,131,800. CONCLUSIONS: In 2015, the Lancet Commission on Global Surgery estimated that 143 million additional surgical procedures are needed in low- and middle-income countries each year, and a subsequent study revealed that approximately 15% of those surgical procedures are neurosurgical. Based on our results, we can conclude that there are approximately 49,940 neurosurgeons currently, worldwide. The availability of neurosurgeons appears to have increased in all geographic regions over the past decade, with Southeast Asia experiencing the greatest growth. Such remarkable expansion should be assessed to determine factors that could play a role in other regions where the acceleration of growth would be beneficial.
RESUMO
OBJECTIVE: The global magnitude of neurosurgical disease is unknown. The authors sought to estimate the surgical and consultative proportion of diseases commonly encountered by neurosurgeons, as well as surgeon case volume and perceived workload. METHODS: An electronic survey was sent to 193 neurosurgeons previously identified via a global surgeon mapping initiative. The survey consisted of three sections aimed at quantifying surgical incidence of neurological disease, consultation incidence, and surgeon demographic data. Surgeons were asked to estimate the proportion of 11 neurological disorders that, in an ideal world, would indicate either neurosurgical operation or neurosurgical consultation. Respondent surgeons indicated their confidence level in each estimate. Demographic and surgical practice characteristics-including case volume and perceived workload-were also captured. RESULTS: Eighty-five neurosurgeons from 57 countries, representing all WHO regions and World Bank income levels, completed the survey. Neurological conditions estimated to warrant neurosurgical consultation with the highest frequency were brain tumors (96%), spinal tumors (95%), hydrocephalus (94%), and neural tube defects (92%), whereas stroke (54%), central nervous system infection (58%), and epilepsy (40%) carried the lowest frequency. Similarly, surgery was deemed necessary for an average of 88% cases of hydrocephalus, 82% of spinal tumors and neural tube defects, and 78% of brain tumors. Degenerative spine disease (42%), stroke (31%), and epilepsy (24%) were found to warrant surgical intervention less frequently. Confidence levels were consistently high among respondents (lower quartile > 70/100 for 90% of questions), and estimates did not vary significantly across WHO regions or among income levels. Surgeons reported performing a mean of 245 cases annually (median 190). On a 100-point scale indicating a surgeon's perceived workload (0-not busy, 100-overworked), respondents selected a mean workload of 75 (median 79). CONCLUSIONS: With a high level of confidence and strong concordance, neurosurgeons estimated that the vast majority of patients with central nervous system tumors, hydrocephalus, or neural tube defects mandate neurosurgical involvement. A significant proportion of other common neurological diseases, such as traumatic brain and spinal injury, vascular anomalies, and degenerative spine disease, demand the attention of a neurosurgeon-whether via operative intervention or expert counsel. These estimates facilitate measurement of the expected annual volume of neurosurgical disease globally.
