Global, regional, and national burden of disorders affecting the nervous system, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

BackgroundDisorders affecting the nervous system are diverse and include neurodevelopmental disorders, late-life neurodegeneration, and newly emergent conditions, such as cognitive impairment following COVID-19. Previous publications from the Global Burden of Disease, Injuries, and Risk Factor Study estimated the burden of 15 neurological conditions in 2015 and 2016, but these analyses did not include neurodevelopmental disorders, as defined by the International Classification of Diseases (ICD)-11, or a subset of cases of congenital, neonatal, and infectious conditions that cause neurological damage. Here, we estimate nervous system health loss caused by 37 unique conditions and their associated risk factors globally, regionally, and nationally from 1990 to 2021.MethodsWe estimated mortality, prevalence, years lived with disability (YLDs), years of life lost (YLLs), and disability-adjusted life-years (DALYs), with corresponding 95% uncertainty intervals (UIs), by age and sex in 204 countries and territories, from 1990 to 2021. We included morbidity and deaths due to neurological conditions, for which health loss is directly due to damage to the CNS or peripheral nervous system. We also isolated neurological health loss from conditions for which nervous system morbidity is a consequence, but not the primary feature, including a subset of congenital conditions (ie, chromosomal anomalies and congenital birth defects), neonatal conditions (ie, jaundice, preterm birth, and sepsis), infectious diseases (ie, COVID-19, cystic echinococcosis, malaria, syphilis, and Zika virus disease), and diabetic neuropathy. By conducting a sequela-level analysis of the health outcomes for these conditions, only cases where nervous system damage occurred were included, and YLDs were recalculated to isolate the non-fatal burden directly attributable to nervous system health loss. A comorbidity correction was used to calculate total prevalence of all conditions that affect the nervous system combined.FindingsGlobally, the 37 conditions affecting the nervous system were collectively ranked as the leading group cause of DALYs in 2021 (443 million, 95% UI 378–521), affecting 3·40 billion (3·20–3·62) individuals (43·1%, 40·5–45·9 of the global population); global DALY counts attributed to these conditions increased by 18·2% (8·7–26·7) between 1990 and 2021. Age-standardised rates of deaths per 100 000 people attributed to these conditions decreased from 1990 to 2021 by 33·6% (27·6–38·8), and age-standardised rates of DALYs attributed to these conditions decreased by 27·0% (21·5–32·4). Age-standardised prevalence was almost stable, with a change of 1·5% (0·7–2·4). The ten conditions with the highest age-standardised DALYs in 2021 were stroke, neonatal encephalopathy, migraine, Alzheimer's disease and other dementias, diabetic neuropathy, meningitis, epilepsy, neurological complications due to preterm birth, autism spectrum disorder, and nervous system cancer.InterpretationAs the leading cause of overall disease burden in the world, with increasing global DALY counts, effective prevention, treatment, and rehabilitation strategies for disorders affecting the nervous system are needed

Effect of Intravitreal Injection of Bevacizumab on Acute Central Serous Chorioretinopathy Patients who Visited Feiz Hospital during 2014–2015 Period

Background: Aim of this clinical trial is the evaluation of the effect of intravitreal injection of bevacizumab on acute central serous chorioretinopathy (CSC). Materials and Methods: In a nonrandomized clinical trial, 36 CSC eyes (with <1-month disease history) were examined. Initially, all the patients underwent posterior and anterior segment examinations as well as complete eye examination to evaluate the best spectacle-corrected visual acuity (BSCVA). Then, optical coherence tomography was performed to confirm the diagnosis. The patients were divided to the two groups each of 18 subjects, which 18 patients received intravitreal injection of bevacizumab (1.25 mg) and the rest of them did not receive any treatment (control group). The patients were health checked by the end of the 1st and 3rd months. Significance level was considered as P < 0.05. Results: In the BSCVA, no significant difference in visual improvement was observed in baseline vision compared to each other (P = 0.481). There was also no significant difference in the vision of intervention and control groups 1 and 3 months after injection (P = 0.379 and P = 0.557). A significant decrement existed in the intervention group compared with the control group in the maximum central macular thickness at 1 month after injection (P = 0.001); however, the difference was not significant when comparing the two groups at baseline and 3 months after injection (P = 0.925 and P = 0.338). Conclusion: In general, according to the results of this study, intravitreal injection of bevacizumab was not effective in improvement of patients with acute CSC, although it had no side effects

Ultrasonography in distinguishing optic neuritis from nonarteritic anterior ischemic optic neuropathy

Background and Objectives: Optic neuritis (ON) and nonarteritic anterior ischemic optic neuropathy (NAION) have some overlapping clinical profiles. We evaluated the usefulness of B-scan ultrasonography in distinguishing ON from NAION by measuring diameter of the optic nerve. Materials and Methods: Consecutive patients with an acute noncompressive unilateral optic neuropathy with relative afferent pupillary defect and onset of visual loss during the last 2 weeks were included. Diagnosis of ON was based on age ≤ 35 years, orbital pain associated with eye movement, and no disk edema, and diagnosis of NAION was based on age ≥ 60 years, no orbital pain associated with eye movement, and presence of disk edema. Age- and gender-matched subjects without ocular disease were selected for comparison. The diameter of the optic nerve was measured by a single radiologist with B-scan ultrasonography. Results: In ON patients, the mean diameter of the affected nerve was significantly larger than that of the unaffected nerve and also larger than that of the right nerve of young controls; P < 0.05. In NAION patients, however, there was no significant difference between the mean diameter of the affected nerve and of the unaffected nerve or the right nerve of elderly controls; P > 0.05. Also, the diameter of the affected nerve was significantly larger in ON than in AION patients; P < 0.05. Conclusion: B-scan ultrasonography is helpful in the early stages of optic neuropathy to distinguish ON from NAION in those cases for which the diagnosis is still uncertain after clinical evaluation

Characterization and identification of candiduria due to Candida species in diabetic patients

Background and Purpose: The presence of Candida yeasts in urine, known as candiduria, is an indicator of infection or colonization of the urinary tract by Candida species. This condition in diabetic patients can be hazardous due to diminished immune system response. The objective of this study was to investigate the incidence of candiduria in diabetic patients and to identify its causative agents. Furthermore, the demographic and laboratory (HbA1c, urine glucose and pH, urine culture colony count, and fasting blood sugar) data and their possible associations with candiduria were investigated. Materials and Methods: This cross-sectional, descriptive study was performed on 305 diabetic patients referred to the diabetes research center, Hamedan, Iran, during April 2015 to September 2015. Urine and blood specimens were collected and urine analysis, urine culture, FBS, and HbA1c tests were performed. Positive cases were subjected to colony count and the causative agents were subsequently identified through the routine identification tests, as well as colony color in CHROMagar Candida medium, and the assimilation patterns in API 20 C auxanographic method. Results: Among the 305 cases, 38 (%12.5) were positive for candiduria. Causative agents were identified as Candida glabrata (n=19, 50%), C. albicans (n=12, 31.6%), C. krusei (n=4, 10.5%), C. tropicalis (n=2, 5.3%), and C. kefyr (n=1, 2.6%). According to the results of the statistical analyses, there were significant association between candiduria and female gender, high FBS and urine glucose, uncontrolled diabetes (HbA1c &ge;8), and acidic urine pH (P<0.05). Conclusion: Considering the high incidence rate of candiduria in diabetic patients, control of diabetes, predisposing factors, and causal relationships between diabetes and candiduria should be highlighted