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

BACKGROUND

Disorders 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.

METHODS

We 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.

FINDINGS

Globally, 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.

INTERPRETATION

As 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.

FUNDING

Bill & Melinda Gates Foundation.

Development of RNA-based assay for rapid detection of SARS-CoV-2 in clinical samples

Introduction

The ongoing spread of pandemic coronavirus disease-19 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is of growing concern. Rapid diagnosis and management of SARS-CoV-2 are crucial for controlling the outbreak in the community. Here, we report the development of a first rapid-colorimetric assay capable of detecting SARS-CoV-2 in the human nasopharyngeal RNA sample in less than 30 min.

Method

We utilized a nanomaterial-based optical sensing platform to detect RNA-dependent RNA polymerase gene of SARS-CoV-2, where the formation of oligo probe-target hybrid led to salt-induced aggregation and change in gold-colloid color from pink to blue visibility range. Accordingly, we found a change in colloid color from pink to blue in assay containing nasopharyngeal RNA sample from the subject with clinically diagnosed COVID-19. The colloid retained pink color when the test includes samples from COVID-19 negative subjects or human papillomavirus-infected women.

Results

The results were validated using nasopharyngeal RNA samples from positive COVID-19 subjects (n = 136). Using real-time polymerase chain reaction as gold standard, the assay was found to have 85.29% sensitivity and 94.12% specificity. The optimized method has detection limit as little as 0.5 ng of SARS-CoV-2 RNA.

Conclusion

We found that the developed assay rapidly detects SARS-CoV-2 RNA in clinical samples in a cost-effective manner and would be useful in pandemic management by facilitating mass screening.

Development of RNA-Based Assay for Rapid Detection of SARS-CoV-2 in Clinical Samples

INTRODUCTION

The ongoing spread of pandemic coronavirus disease-19 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is of growing concern. Rapid diagnosis and management of SARS-CoV-2 are crucial for controlling the outbreak in the community. Here, we report the development of a first rapid-colorimetric assay capable of detecting SARS-CoV-2 in the human nasopharyngeal RNA sample in less than 30 min.

METHOD

We utilized a nanomaterial-based optical sensing platform to detect RNA-dependent RNA polymerase gene of SARS-CoV-2, where the formation of oligo probe-target hybrid led to salt-induced aggregation and change in gold-colloid color from pink to blue visibility range. Accordingly, we found a change in colloid color from pink to blue in assay containing nasopharyngeal RNA sample from the subject with clinically diagnosed COVID-19. The colloid retained pink color when the test includes samples from COVID-19 negative subjects or human papillomavirus-infected women.

RESULTS

The results were validated using nasopharyngeal RNA samples from positive COVID-19 subjects (n = 136). Using real-time polymerase chain reaction as gold standard, the assay was found to have 85.29% sensitivity and 94.12% specificity. The optimized method has detection limit as little as 0.5 ng of SARS-CoV-2 RNA.

CONCLUSION

We found that the developed assay rapidly detects SARS-CoV-2 RNA in clinical samples in a cost-effective manner and would be useful in pandemic management by facilitating mass screening.

Influence of genetic polymorphism in renin-angiotensin system-candidate genes on urinary trefoil family factor 3 levels in children with congenital anomalies of kidney and urinary tract

BACKGROUND

This cross-sectional study aimed to determine the influence of genetic polymorphism in two renin-angiotensin system (RAS)-candidate genes on urinary trefoil family factor 3 (TFF3) levels in children with congenital anomalies of kidney and urinary tract (CAKUT).

METHODS

The study included fifty children with CAKUT (PUV, VUR, and PUJO) and twenty age-matched controls. Urinary TFF3 levels were measured by enzyme-linked immunosorbent assay. Detection of genetic polymorphisms in two genes, i.e., I/D polymorphism (SNP at rs4340) in angiotensin-converting enzyme (ACE) and A/T polymorphism in the angiotensin II receptor type-2 (AT2R) due to point mutation at rs3736556 was performed by polymerase chain reaction. Progressive deterioration in kidney function was defined as fall in GFR to < 60 ml/min/1.73 m² and/or progressive scarring.

RESULTS

In our cohort, the genotypic distribution of patients and controls showed no difference. Progressive functional deterioration was significantly associated with the presence of D allele (p = 0.0004), A allele (p = 0.005), and both (p < 0.0001) in patients. Significantly raised TFF3 levels were detected in the urine of children having D allele (D/D > I/D > I/I; p < 0.0001) and A allele (A/A > A/T > TT; p < 0.0001). Also, children with both D/D and A/A allelic genotypes had significantly elevated urinary TFF3 compared to those having either of them.

CONCLUSIONS

The presence of D allele and/or A allele is significantly associated with progressive functional deterioration and elevated urinary TFF3 levels. These findings support the role of angiotensin II-AT2R-NF-κB interaction in progressive deterioration of kidney function and subsequent TFF3 expression in CAKUT.

Prevalence of hearing loss in India

Background Despite abundant literature, a clear and coherent understanding of hearing loss (HL) in India is limited by the wide disparity in studies. Methods We did a review of published peer-reviewed journal articles. Studies reporting the prevalence and degree of HL in India from 1980 to 2020 were included. Information was gathered on the population characteristics, methodology applied and the prevalence of hearing impairment. The data were analysed to identify trends and at-risk sections of population in various categories. Results Four hundred and forty studies were identified after a database search; 29 full-length articles were selected for final analysis. Using a 3-step screening protocol, hearing impairment (abnormal auditory brainstem response/auditory steady state response) in neonates ranged between 1.59 and 8.8 per 1000 births. Among 'at risk' neonates, it ranged from 7 to 49.18 per 1000 births. In children the prevalence of HL was 6.6% to 16.47%. Otitis media was the most common cause of HL in children. Community-based studies (all ages) reported prevalence of HL between 6% and 26.9% and prevalence of disabling HL between 4.5% and 18.3%. Rural areas and elderly showed a higher prevalence of hearing impairment. Conclusion Despite India's improving health indices, hearing disability remains persistently high. It is a major contributor to the loss of personal potential and a financial strain for the individual and the country. A large-scale multicentric study to identify the degree and type of HL, social awareness campaigns, widespread neonatal screening, strengthening treatment facilities and well-funded rehabilitation programmes can counter the rising prevalence of hearing impairment.

Association of kidney functions with a cascade of care for diabetes and hypertension in two geographically distinct Indian cohorts

AIM

Type 2 diabetes (T2DM) and hypertension (HTN) are the main modifiable risk factors of chronic kidney disease (CKD), among the known traditional and non-traditional risk factors.

METHODS

We determined the prevalence and care-cascade of these modifiable CKD-risk factors and their association with socioeconomic status in adjoining Lucknow and Puducherry cities of India.

RESULTS

439 participants reported no CKD were recruited. Serum analysis revealed an Estimated Glomerular Filtration Rate (eGFR) ≥ 90 ml/min/1.73 m² in 60.36% of the population. Of them, 55.85% had HTN and/or T2DM as CKD-risk factors; however, less than half of this population was unaware of their CKD-risk status. Awareness and treatment were significantly higher in Puducherry and were associated with literacy, occupation, and residence place. Although the CKD-risk population was about two times higher in Puducherry than Lucknow, the populations with mild-low eGFR were comparable in the two regions. Moreover, in Lucknow, mild-low eGFR and low awareness were more prevalent among the younger participants (<30 years), relative to Puducherry.

CONCLUSIONS

Despite a higher prevalence of CKD-risk factors in Puducherry, populations with mild-low eGFR were comparable to Lucknow. More heightened awareness and better care cascade for CKD-risk factors in Puducherry may prevent or delay eGFR reduction.

MO649DIAGNOSTIC TESTS OF NOVEL URINARY BIOMARKERS TO IDENTIFY EARLY STAGES OF NEPHROPATHY IN NON HYPERTENSIVE TYPE 2 DIABETIC MELLITUS

Background and Aims

Activation of RAS and tubulointerstitial damage might be seen in pre-albuminuria stage of diabetic nephropathy. Here, diagnostic tests of urinary Angiotensinogen, Cystatin C, Neutrophil gelatinase associated lipocalin and IL 18 have been studied in pre-microalbuminuria diabetic patients.

Method

Total 952 Diabetic screened for Nephropathy (e-GFR ≥120&ACR≥30), among them 120 cases were followed up for one year. At one year they were classified in to Hyperfiltration43, Normoalbuminuria29 and Microalbuminuria48 groups. Another 63 Diabetes without nephropathy were included as controls. Hypertension, on ACEI/ARB, e-GFR&lt;60ml/min/1.73m2 and all Macroalbuminuria conditions were excluded. All were subjected to urine protein, ACR, HbA1c,e-GFR, along with urinary bio markers(IL-18, Cystatin-C, NGAL and Angiotensinogen). Comparative analysis of all groups, Diagnostic tests, correlation and logistic regression were analysed.

Results

Urinary IL18/Cr, Cystatin /Cr. and Angiotensiogen /Cr. levels were higher in groups of hyper filtration (13.47, 12.11 & 8.43mg/g), Normoalbuminuria (9.24,11.74&9.15mg/g) and microalbuminuria(11.59,14.48&10.24mg/g) than controls(7.38,8.39&1.26mg/g) but not NGAL/Cr. in all groups. High levels were significant in all except Cystatin/Cr. & IL18/Cr. in normoalbuminuria group. The AUC, sensitivity and specificity of Angiotensinogen (0.9, 90% and 80%) ACR (0.69, 40% and 100%) and e-GFR (0.6,37 and 100%)respectively. AUC of other biomarkers viz, IL 18/cr. Cystatin/Cr and NGAL/Cr. were 0.65, 0.64 and 0.51 respectively. Angiotensinogen/Cr and IL18/Cr showed correlation with log albuminuria r-0.3 p 0.00 and r-0.28 p 0.00 respectively; NGAL with log e-GFR (r-0.28 p0.00).Multivariate logistic analysis showed Odds of contracting nephropathy is 7.5 times having higher values of Log Angio/Cr.

Conclusion

Urinary Angiotensinogen has higher diagnostic value than ACR and e-GFR followed by IL 18 and Cystatin to diagnose DN at the pre-albuminuric stages but not urinary NGAL.

Ethylmalonic encephalopathy ETHE1 p. D165H mutation alters the mitochondrial function in human skeletal muscle proteome

Ethylmalonic encephalopathy (EE) is a rare autosomal recessive inborn error of metabolism. To study the molecular effects of ETHE1 p. D165H mutation, we employed mass spectrometry-based mitochondrial proteome and phosphoproteome profiling in the human skeletal muscle. Eighty-six differentially altered proteins were identified, of which thirty-seven mitochondrial proteins were differentially expressed, and most of the proteins (37%) were down-regulated in the OXPHOS complex-IV. Also, nine phosphopeptides that correspond to eight mitochondrial proteins were significantly affected in EE patient. These altered proteins recognized are involved in several pathways and molecular functions, predominantly in oxidoreductase activity. This is the first study that has integrated proteome and phosphoproteome of skeletal muscle and identified multiple proteins associated in the pathogenesis of EE.

Options of Renal Replacement Therapy in CKDu

Patients with advanced Chronic Kidney Disease of Unknown origin (CKDu) need to plan for renal replacement therapy. The patients usually affected are probably best served with living-related renal transplantation. Potential donors from the same area are possibly at risk for developing CKDu and need close monitoring post kidney donation. Peritoneal dialysis (PD) is probably a better option as hemodialysis (HD) centers are located in urban areas only and patients have the convenience of receiving therapy at home. The “PD first” pilot project of Sri Lanka is a unique initiative that trains community physicians to offer PD to patients with advanced CKDu. In Telengana and Andhra Pradesh, the Aarogyasri insurance scheme provides for poor patients to avail of free HD and transplantation in government and private hospitals. Much more needs to be done to care for all those who are affected. A public–private partnership model for providing comprehensive care to patients with advanced CKDu can be undertaken in all areas affected by CKDu that makes renal replacement therapy (RRT) available and accessible, irrespective of financial and social limitations.

A Systematic Study of the Prevalence and Risk Factors of CKD in Uddanam, India

Introduction

Despite reports of a high prevalence of chronic kidney disease (CKD) from the coastal Uddanam region of Andhra Pradesh, India, there are no accurate data on the distribution of kidney function abnormalities and CKD risk factors in this region.

Methods

A total of 2419 participants were recruited through multistage cluster random sampling from 67 villages. Serum creatinine and urine protein creatinine ratio were measured using validated methodologies. All abnormal estimated glomerular filtration rate (eGFR) and urine protein creatinine ratio values were reconfirmed after 3 months. A range of sociodemographic factors were evaluated for their association with CKD using Poisson regression.

Results

Of 2402 eligible subjects (mean ± SD age, 45.67 ± 13.29 years; 51% female), 506 (21.07%) had CKD (mean ± SD age, 51.79 ± 13.12 years; 41.3% female). A total of 246 (10.24%) had eGFR <60 ml/min/1.73 m², whereas 371 (15.45%) had an elevated urine protein creatinine ratio (>0.15 g/g). The poststratified estimates, adjusted for age and sex distribution of the region for CKD prevalence, are 18.7% (range, 16.4%–21.0%) overall and 21.3% (range, 18.2%–24.4% ) and 16.2% (range, 13.7%–18.8%) in men and women, respectively. Older age, male sex, tobacco use, hypertension, and family history of CKD were independently associated with CKD. Compared with those with higher eGFR, those with eGFR <60 ml/min/1.73m² were older, were more likely to be uneducated, manual laborers/farmers, or tobacco users, and were more likely to have hypertension, a family history of CKD, a diagnosis of heart disease, and a lower body mass index. Among those with low eGFR, there was no difference between those with urine protein creatinine ratio <0.15 or >0.15, except a lower frequency of males in the former.

Conclusion

We confirmed the high prevalence of CKD in the adult population of Uddanam. The cause was not apparent in a majority. Subjects with a low eGFR with or without elevated proteinuria were phenotypically distinct from those with proteinuria and preserved eGFR. Our data suggest the need to apply a population-based approach to screening and prevention and studies to understand the causes of CKD in this region.

Estimating global injuries morbidity and mortality: methods and data used in the Global Burden of Disease 2017 study

BACKGROUND

While there is a long history of measuring death and disability from injuries, modern research methods must account for the wide spectrum of disability that can occur in an injury, and must provide estimates with sufficient demographic, geographical and temporal detail to be useful for policy makers. The Global Burden of Disease (GBD) 2017 study used methods to provide highly detailed estimates of global injury burden that meet these criteria.

METHODS

In this study, we report and discuss the methods used in GBD 2017 for injury morbidity and mortality burden estimation. In summary, these methods included estimating cause-specific mortality for every cause of injury, and then estimating incidence for every cause of injury. Non-fatal disability for each cause is then calculated based on the probabilities of suffering from different types of bodily injury experienced.

RESULTS

GBD 2017 produced morbidity and mortality estimates for 38 causes of injury. Estimates were produced in terms of incidence, prevalence, years lived with disability, cause-specific mortality, years of life lost and disability-adjusted life-years for a 28-year period for 22 age groups, 195 countries and both sexes.

CONCLUSIONS

GBD 2017 demonstrated a complex and sophisticated series of analytical steps using the largest known database of morbidity and mortality data on injuries. GBD 2017 results should be used to help inform injury prevention policy making and resource allocation. We also identify important avenues for improving injury burden estimation in the future.

Global injury morbidity and mortality from 1990 to 2017: results from the Global Burden of Disease Study 2017

BACKGROUND

Past research in population health trends has shown that injuries form a substantial burden of population health loss. Regular updates to injury burden assessments are critical. We report Global Burden of Disease (GBD) 2017 Study estimates on morbidity and mortality for all injuries.

METHODS

We reviewed results for injuries from the GBD 2017 study. GBD 2017 measured injury-specific mortality and years of life lost (YLLs) using the Cause of Death Ensemble model. To measure non-fatal injuries, GBD 2017 modelled injury-specific incidence and converted this to prevalence and years lived with disability (YLDs). YLLs and YLDs were summed to calculate disability-adjusted life years (DALYs).

FINDINGS

In 1990, there were 4 260 493 (4 085 700 to 4 396 138) injury deaths, which increased to 4 484 722 (4 332 010 to 4 585 554) deaths in 2017, while age-standardised mortality decreased from 1079 (1073 to 1086) to 738 (730 to 745) per 100 000. In 1990, there were 354 064 302 (95% uncertainty interval: 338 174 876 to 371 610 802) new cases of injury globally, which increased to 520 710 288 (493 430 247 to 547 988 635) new cases in 2017. During this time, age-standardised incidence decreased non-significantly from 6824 (6534 to 7147) to 6763 (6412 to 7118) per 100 000. Between 1990 and 2017, age-standardised DALYs decreased from 4947 (4655 to 5233) per 100 000 to 3267 (3058 to 3505).

INTERPRETATION

Injuries are an important cause of health loss globally, though mortality has declined between 1990 and 2017. Future research in injury burden should focus on prevention in high-burden populations, improving data collection and ensuring access to medical care.

Chronic Kidney Disease of Unknown Origin - What do we know?

The global burden of CKD is considerable and has risen dramatically over the past 20 years. Recently, CKD of unknown origin (CKDu), a form of CKD among rural agricultural communities has been reported worldwide. There is no strong evidence for a single cause of CKDu. Basically, it is a phenotypic environmentally acquired disease with a combination of occupational and social factors. Across all geographical regions, CKDu was most frequently associated with men, middle age, snake bite, infection, and exposure to agrochemicals, heavy metals, herbal drugs, heat stress, and dietary exposures. CKDu has emerged as a challenge in certain regions of the world as there is no acceptable global definition for CKDu. There is an urgent need for health promotion at individual and community levels for early screening of risk factors and timely management. It is also important to strengthen the health service networks for a better quality of life and patient safety as well as adequate financing. Further etiological and interventional research is needed to reduce preventable regional risk factors as well as to develop proactive and comprehensive approaches to prevent and treat the disease.

Study to Test and Operationalize Preventive Approaches for CKD of Undetermined Etiology in Andhra Pradesh, India

INTRODUCTION

High prevalence of chronic kidney disease (CKD) not associated with known risk factors has been reported from coastal districts of Andhra Pradesh. The Study to Test and Operationalize Preventive Approaches for Chronic Kidney Disease of Undetermined Etiology in Andhra Pradesh (STOP CKDu AP) aims to ascertain the burden (prevalence and incidence) of CKD, the risk factor profile, and the community perceptions about the disease in the Uddanam area of Andhra Pradesh.

METHODS

Study participants will be sampled from the Uddanam area using multistage cluster random sampling. Information will be collected on the demographic profile, occupational history, and presence of conventional as well as nonconventional risk factors. Glomerular filtration rate (GFR) will be estimated using the Chronic Kidney Disease Epidemiology Collaboration equation, and proteinuria will be measured. All abnormal values will be confirmed by repeat testing after 3 months. Cases of CKD not associated with identified etiologies will be identified. Biospecimens will be stored to explore future hypotheses. The entire cohort will be followed up every 6 months to determine the incidence of CKD and to identify risk factors for decline in kidney function. Qualitative studies will be performed to understand the community perceptions and expectations with respect to the interventions.

IMPLICATIONS

CKD is an important public health challenge in low- and middle-income countries. This study will establish the prevalence and determine the incidence of CKD not associated with known risk factors in a reported high-burden region, and will provide insights to help design targeted health systems responses. The findings will contribute to the policy development to tackle CKD in the region and will permit international comparisons with other regions with similar high prevalence.

Global, regional, and national burden of Alzheimer's disease and other dementias, 1990-2016: a systematic analysis for the Global Burden of Disease Study 2016

BACKGROUND

The number of individuals living with dementia is increasing, negatively affecting families, communities, and health-care systems around the world. A successful response to these challenges requires an accurate understanding of the dementia disease burden. We aimed to present the first detailed analysis of the global prevalence, mortality, and overall burden of dementia as captured by the Global Burden of Diseases, Injuries, and Risk Factors (GBD) Study 2016, and highlight the most important messages for clinicians and neurologists.

METHODS

GBD 2016 obtained data on dementia from vital registration systems, published scientific literature and surveys, and data from health-service encounters on deaths, excess mortality, prevalence, and incidence from 195 countries and territories from 1990 to 2016, through systematic review and additional data-seeking efforts. To correct for differences in cause of death coding across time and locations, we modelled mortality due to dementia using prevalence data and estimates of excess mortality derived from countries that were most likely to code deaths to dementia relative to prevalence. Data were analysed by standardised methods to estimate deaths, prevalence, years of life lost (YLLs), years of life lived with disability (YLDs), and disability-adjusted life-years (DALYs; computed as the sum of YLLs and YLDs), and the fractions of these metrics that were attributable to four risk factors that met GBD criteria for assessment (high body-mass index [BMI], high fasting plasma glucose, smoking, and a diet high in sugar-sweetened beverages).

FINDINGS

In 2016, the global number of individuals who lived with dementia was 43·8 million (95% uncertainty interval [UI] 37·8-51·0), increased from 20.2 million (17·4-23·5) in 1990. This increase of 117% (95% UI 114-121) contrasted with a minor increase in age-standardised prevalence of 1·7% (1·0-2·4), from 701 cases (95% UI 602-815) per 100 000 population in 1990 to 712 cases (614-828) per 100 000 population in 2016. More women than men had dementia in 2016 (27·0 million, 95% UI 23·3-31·4, vs 16.8 million, 14.4-19.6), and dementia was the fifth leading cause of death globally, accounting for 2·4 million (95% UI 2·1-2·8) deaths. Overall, 28·8 million (95% UI 24·5-34·0) DALYs were attributed to dementia; 6·4 million (95% UI 3·4-10·5) of these could be attributed to the modifiable GBD risk factors of high BMI, high fasting plasma glucose, smoking, and a high intake of sugar-sweetened beverages.

INTERPRETATION

The global number of people living with dementia more than doubled from 1990 to 2016, mainly due to increases in population ageing and growth. Although differences in coding for causes of death and the heterogeneity in case-ascertainment methods constitute major challenges to the estimation of the burden of dementia, future analyses should improve on the methods for the correction of these biases. Until breakthroughs are made in prevention or curative treatment, dementia will constitute an increasing challenge to health-care systems worldwide.

FUNDING

Bill & Melinda Gates Foundation.

The increasing burden of diabetes and variations among the states of India: the Global Burden of Disease Study 1990-2016

BACKGROUND

The burden of diabetes is increasing rapidly in India but a systematic understanding of its distribution and time trends is not available for every state of India. We present a comprehensive analysis of the time trends and heterogeneity in the distribution of diabetes burden across all states of India between 1990 and 2016.

METHODS

We analysed the prevalence and disability-adjusted life-years (DALYs) of diabetes in the states of India from 1990 to 2016 using all available data sources that could be accessed as part of the Global Burden of Diseases, Injuries, and Risk Factors Study 2016, and assessed heterogeneity across the states. The states were placed in four groups based on epidemiological transition level (ETL), defined on the basis of the ratio of DALYs from communicable diseases to those from non-communicable diseases and injuries combined, with a low ratio denoting high ETL and vice versa. We assessed the contribution of risk factors to diabetes DALYs and the relation of overweight (body-mass index 25 kg/m2 or more) with diabetes prevalence. We calculated 95% uncertainty intervals (UIs) for the point estimates.

FINDINGS

The number of people with diabetes in India increased from 26·0 million (95% UI 23·4-28·6) in 1990 to 65·0 million (58·7-71·1) in 2016. The prevalence of diabetes in adults aged 20 years or older in India increased from 5·5% (4·9-6·1) in 1990 to 7·7% (6·9-8·4) in 2016. The prevalence in 2016 was highest in Tamil Nadu and Kerala (high ETL) and Delhi (higher-middle ETL), followed by Punjab and Goa (high ETL) and Karnataka (higher-middle ETL). The age-standardised DALY rate for diabetes increased in India by 39·6% (32·1-46·7) from 1990 to 2016, which was the highest increase among major non-communicable diseases. The age-standardised diabetes prevalence and DALYs increased in every state, with the percentage increase among the highest in several states in the low and lower-middle ETL state groups. The most important risk factor for diabetes in India was overweight to which 36·0% (22·6-49·2) of the diabetes DALYs in 2016 could be attributed. The prevalence of overweight in adults in India increased from 9·0% (8·7-9·3) in 1990 to 20·4% (19·9-20·8) in 2016; this prevalence increased in every state of the country. For every 100 overweight adults aged 20 years or older in India, there were 38 adults (34-42) with diabetes, compared with the global average of 19 adults (17-21) in 2016.

INTERPRETATION

The increase in health loss from diabetes since 1990 in India is the highest among major non-communicable diseases. With this increase observed in every state of the country, and the relative rate of increase highest in several less developed low ETL states, policy action that takes these state-level differences into account is needed urgently to control this potentially explosive public health situation.

FUNDING

Bill & Melinda Gates Foundation; and Indian Council of Medical Research, Department of Health Research, Ministry of Health and Family Welfare, Government of India.

Global, regional, and national age-sex-specific mortality and life expectancy, 1950-2017: a systematic analysis for the Global Burden of Disease Study 2017

BACKGROUND

Assessments of age-specific mortality and life expectancy have been done by the UN Population Division, Department of Economics and Social Affairs (UNPOP), the United States Census Bureau, WHO, and as part of previous iterations of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD). Previous iterations of the GBD used population estimates from UNPOP, which were not derived in a way that was internally consistent with the estimates of the numbers of deaths in the GBD. The present iteration of the GBD, GBD 2017, improves on previous assessments and provides timely estimates of the mortality experience of populations globally.

METHODS

The GBD uses all available data to produce estimates of mortality rates between 1950 and 2017 for 23 age groups, both sexes, and 918 locations, including 195 countries and territories and subnational locations for 16 countries. Data used include vital registration systems, sample registration systems, household surveys (complete birth histories, summary birth histories, sibling histories), censuses (summary birth histories, household deaths), and Demographic Surveillance Sites. In total, this analysis used 8259 data sources. Estimates of the probability of death between birth and the age of 5 years and between ages 15 and 60 years are generated and then input into a model life table system to produce complete life tables for all locations and years. Fatal discontinuities and mortality due to HIV/AIDS are analysed separately and then incorporated into the estimation. We analyse the relationship between age-specific mortality and development status using the Socio-demographic Index, a composite measure based on fertility under the age of 25 years, education, and income. There are four main methodological improvements in GBD 2017 compared with GBD 2016: 622 additional data sources have been incorporated; new estimates of population, generated by the GBD study, are used; statistical methods used in different components of the analysis have been further standardised and improved; and the analysis has been extended backwards in time by two decades to start in 1950.

FINDINGS

Globally, 18·7% (95% uncertainty interval 18·4-19·0) of deaths were registered in 1950 and that proportion has been steadily increasing since, with 58·8% (58·2-59·3) of all deaths being registered in 2015. At the global level, between 1950 and 2017, life expectancy increased from 48·1 years (46·5-49·6) to 70·5 years (70·1-70·8) for men and from 52·9 years (51·7-54·0) to 75·6 years (75·3-75·9) for women. Despite this overall progress, there remains substantial variation in life expectancy at birth in 2017, which ranges from 49·1 years (46·5-51·7) for men in the Central African Republic to 87·6 years (86·9-88·1) among women in Singapore. The greatest progress across age groups was for children younger than 5 years; under-5 mortality dropped from 216·0 deaths (196·3-238·1) per 1000 livebirths in 1950 to 38·9 deaths (35·6-42·83) per 1000 livebirths in 2017, with huge reductions across countries. Nevertheless, there were still 5·4 million (5·2-5·6) deaths among children younger than 5 years in the world in 2017. Progress has been less pronounced and more variable for adults, especially for adult males, who had stagnant or increasing mortality rates in several countries. The gap between male and female life expectancy between 1950 and 2017, while relatively stable at the global level, shows distinctive patterns across super-regions and has consistently been the largest in central Europe, eastern Europe, and central Asia, and smallest in south Asia. Performance was also variable across countries and time in observed mortality rates compared with those expected on the basis of development.

INTERPRETATION

This analysis of age-sex-specific mortality shows that there are remarkably complex patterns in population mortality across countries. The findings of this study highlight global successes, such as the large decline in under-5 mortality, which reflects significant local, national, and global commitment and investment over several decades. However, they also bring attention to mortality patterns that are a cause for concern, particularly among adult men and, to a lesser extent, women, whose mortality rates have stagnated in many countries over the time period of this study, and in some cases are increasing.

FUNDING

Bill & Melinda Gates Foundation.

Measuring progress from 1990 to 2017 and projecting attainment to 2030 of the health-related Sustainable Development Goals for 195 countries and territories: a systematic analysis for the Global Burden of Disease Study 2017

BACKGROUND

Efforts to establish the 2015 baseline and monitor early implementation of the UN Sustainable Development Goals (SDGs) highlight both great potential for and threats to improving health by 2030. To fully deliver on the SDG aim of "leaving no one behind", it is increasingly important to examine the health-related SDGs beyond national-level estimates. As part of the Global Burden of Diseases, Injuries, and Risk Factors Study 2017 (GBD 2017), we measured progress on 41 of 52 health-related SDG indicators and estimated the health-related SDG index for 195 countries and territories for the period 1990-2017, projected indicators to 2030, and analysed global attainment.

METHODS

We measured progress on 41 health-related SDG indicators from 1990 to 2017, an increase of four indicators since GBD 2016 (new indicators were health worker density, sexual violence by non-intimate partners, population census status, and prevalence of physical and sexual violence [reported separately]). We also improved the measurement of several previously reported indicators. We constructed national-level estimates and, for a subset of health-related SDGs, examined indicator-level differences by sex and Socio-demographic Index (SDI) quintile. We also did subnational assessments of performance for selected countries. To construct the health-related SDG index, we transformed the value for each indicator on a scale of 0-100, with 0 as the 2·5th percentile and 100 as the 97·5th percentile of 1000 draws calculated from 1990 to 2030, and took the geometric mean of the scaled indicators by target. To generate projections through 2030, we used a forecasting framework that drew estimates from the broader GBD study and used weighted averages of indicator-specific and country-specific annualised rates of change from 1990 to 2017 to inform future estimates. We assessed attainment of indicators with defined targets in two ways: first, using mean values projected for 2030, and then using the probability of attainment in 2030 calculated from 1000 draws. We also did a global attainment analysis of the feasibility of attaining SDG targets on the basis of past trends. Using 2015 global averages of indicators with defined SDG targets, we calculated the global annualised rates of change required from 2015 to 2030 to meet these targets, and then identified in what percentiles the required global annualised rates of change fell in the distribution of country-level rates of change from 1990 to 2015. We took the mean of these global percentile values across indicators and applied the past rate of change at this mean global percentile to all health-related SDG indicators, irrespective of target definition, to estimate the equivalent 2030 global average value and percentage change from 2015 to 2030 for each indicator.

FINDINGS

The global median health-related SDG index in 2017 was 59·4 (IQR 35·4-67·3), ranging from a low of 11·6 (95% uncertainty interval 9·6-14·0) to a high of 84·9 (83·1-86·7). SDG index values in countries assessed at the subnational level varied substantially, particularly in China and India, although scores in Japan and the UK were more homogeneous. Indicators also varied by SDI quintile and sex, with males having worse outcomes than females for non-communicable disease (NCD) mortality, alcohol use, and smoking, among others. Most countries were projected to have a higher health-related SDG index in 2030 than in 2017, while country-level probabilities of attainment by 2030 varied widely by indicator. Under-5 mortality, neonatal mortality, maternal mortality ratio, and malaria indicators had the most countries with at least 95% probability of target attainment. Other indicators, including NCD mortality and suicide mortality, had no countries projected to meet corresponding SDG targets on the basis of projected mean values for 2030 but showed some probability of attainment by 2030. For some indicators, including child malnutrition, several infectious diseases, and most violence measures, the annualised rates of change required to meet SDG targets far exceeded the pace of progress achieved by any country in the recent past. We found that applying the mean global annualised rate of change to indicators without defined targets would equate to about 19% and 22% reductions in global smoking and alcohol consumption, respectively; a 47% decline in adolescent birth rates; and a more than 85% increase in health worker density per 1000 population by 2030.

INTERPRETATION

The GBD study offers a unique, robust platform for monitoring the health-related SDGs across demographic and geographic dimensions. Our findings underscore the importance of increased collection and analysis of disaggregated data and highlight where more deliberate design or targeting of interventions could accelerate progress in attaining the SDGs. Current projections show that many health-related SDG indicators, NCDs, NCD-related risks, and violence-related indicators will require a concerted shift away from what might have driven past gains-curative interventions in the case of NCDs-towards multisectoral, prevention-oriented policy action and investments to achieve SDG aims. Notably, several targets, if they are to be met by 2030, demand a pace of progress that no country has achieved in the recent past. The future is fundamentally uncertain, and no model can fully predict what breakthroughs or events might alter the course of the SDGs. What is clear is that our actions-or inaction-today will ultimately dictate how close the world, collectively, can get to leaving no one behind by 2030.

FUNDING

Bill & Melinda Gates Foundation.

Population and fertility by age and sex for 195 countries and territories, 1950-2017: a systematic analysis for the Global Burden of Disease Study 2017

BACKGROUND

Population estimates underpin demographic and epidemiological research and are used to track progress on numerous international indicators of health and development. To date, internationally available estimates of population and fertility, although useful, have not been produced with transparent and replicable methods and do not use standardised estimates of mortality. We present single-calendar year and single-year of age estimates of fertility and population by sex with standardised and replicable methods.

METHODS

We estimated population in 195 locations by single year of age and single calendar year from 1950 to 2017 with standardised and replicable methods. We based the estimates on the demographic balancing equation, with inputs of fertility, mortality, population, and migration data. Fertility data came from 7817 location-years of vital registration data, 429 surveys reporting complete birth histories, and 977 surveys and censuses reporting summary birth histories. We estimated age-specific fertility rates (ASFRs; the annual number of livebirths to women of a specified age group per 1000 women in that age group) by use of spatiotemporal Gaussian process regression and used the ASFRs to estimate total fertility rates (TFRs; the average number of children a woman would bear if she survived through the end of the reproductive age span [age 10-54 years] and experienced at each age a particular set of ASFRs observed in the year of interest). Because of sparse data, fertility at ages 10-14 years and 50-54 years was estimated from data on fertility in women aged 15-19 years and 45-49 years, through use of linear regression. Age-specific mortality data came from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 estimates. Data on population came from 1257 censuses and 761 population registry location-years and were adjusted for underenumeration and age misreporting with standard demographic methods. Migration was estimated with the GBD Bayesian demographic balancing model, after incorporating information about refugee migration into the model prior. Final population estimates used the cohort-component method of population projection, with inputs of fertility, mortality, and migration data. Population uncertainty was estimated by use of out-of-sample predictive validity testing. With these data, we estimated the trends in population by age and sex and in fertility by age between 1950 and 2017 in 195 countries and territories.

FINDINGS

From 1950 to 2017, TFRs decreased by 49·4% (95% uncertainty interval [UI] 46·4-52·0). The TFR decreased from 4·7 livebirths (4·5-4·9) to 2·4 livebirths (2·2-2·5), and the ASFR of mothers aged 10-19 years decreased from 37 livebirths (34-40) to 22 livebirths (19-24) per 1000 women. Despite reductions in the TFR, the global population has been increasing by an average of 83·8 million people per year since 1985. The global population increased by 197·2% (193·3-200·8) since 1950, from 2·6 billion (2·5-2·6) to 7·6 billion (7·4-7·9) people in 2017; much of this increase was in the proportion of the global population in south Asia and sub-Saharan Africa. The global annual rate of population growth increased between 1950 and 1964, when it peaked at 2·0%; this rate then remained nearly constant until 1970 and then decreased to 1·1% in 2017. Population growth rates in the southeast Asia, east Asia, and Oceania GBD super-region decreased from 2·5% in 1963 to 0·7% in 2017, whereas in sub-Saharan Africa, population growth rates were almost at the highest reported levels ever in 2017, when they were at 2·7%. The global average age increased from 26·6 years in 1950 to 32·1 years in 2017, and the proportion of the population that is of working age (age 15-64 years) increased from 59·9% to 65·3%. At the national level, the TFR decreased in all countries and territories between 1950 and 2017; in 2017, TFRs ranged from a low of 1·0 livebirths (95% UI 0·9-1·2) in Cyprus to a high of 7·1 livebirths (6·8-7·4) in Niger. The TFR under age 25 years (TFU25; number of livebirths expected by age 25 years for a hypothetical woman who survived the age group and was exposed to current ASFRs) in 2017 ranged from 0·08 livebirths (0·07-0·09) in South Korea to 2·4 livebirths (2·2-2·6) in Niger, and the TFR over age 30 years (TFO30; number of livebirths expected for a hypothetical woman ageing from 30 to 54 years who survived the age group and was exposed to current ASFRs) ranged from a low of 0·3 livebirths (0·3-0·4) in Puerto Rico to a high of 3·1 livebirths (3·0-3·2) in Niger. TFO30 was higher than TFU25 in 145 countries and territories in 2017. 33 countries had a negative population growth rate from 2010 to 2017, most of which were located in central, eastern, and western Europe, whereas population growth rates of more than 2·0% were seen in 33 of 46 countries in sub-Saharan Africa. In 2017, less than 65% of the national population was of working age in 12 of 34 high-income countries, and less than 50% of the national population was of working age in Mali, Chad, and Niger.

INTERPRETATION

Population trends create demographic dividends and headwinds (ie, economic benefits and detriments) that affect national economies and determine national planning needs. Although TFRs are decreasing, the global population continues to grow as mortality declines, with diverse patterns at the national level and across age groups. To our knowledge, this is the first study to provide transparent and replicable estimates of population and fertility, which can be used to inform decision making and to monitor progress.

FUNDING

Bill & Melinda Gates Foundation.

A review of non-invasive imaging in extramammary Paget's disease

Extramammary Paget's Disease (EMPD) is a rare intraepithelial adenocarcinoma that classically manifests with pruritic, erythematous and scaling plaques. The clinical picture frequently mimics inflammatory or infectious conditions and is thus commonly misdiagnosed. The assessment of tumour margins is equally challenging as tumours have a propensity to spread beyond clinically visible boundaries. Appropriate non-invasive diagnostic tools can assist in the early detection, diagnosis and management of EMPD. This paper will review the literature on non-invasive imaging modalities used in EMPD. Articles from the PubMed database were selected based on relevance to the topic of this review. Articles that were not specific to EMPD and non-invasive imaging were excluded. Search strategy is further described in the methods section below. Eighteen articles were selected for this review: six PET/CT, five reflectance confocal microscopy (RCM), two photodynamic diagnosis (PDD), two dermoscopy, two MRI and one optical coherence tomography (OCT) paper(s). Dermoscopy, PDD, RCM and OCT can help to distinguish malignant conditions, including EMPD, from benign conditions. RCM and OCT can identify atypical cells in real-time, and have the potential to improve the accuracy of surgical margins intraoperatively and overall management. Distinctive confocal characteristics of EMPD have been described using RCM. The sensitivity and specificity of these findings require additional validation. Radiographic techniques also play a central role in the diagnosis of EMPD and assessment of disease spread. PET/CT and MRI can detect primary disease, nodal and distant metastases, with superior delineation of disease spread on MRI. Limitations of PET/CT are mainly related to primary tumour thickness, and size and FDG-avidity of nodal and distant metastases. Limitations of MRI include the fact that few studies have examined its use in EMPD; additional research is warranted. Randomized controlled trials and large prospective studies evaluating the use of non-invasive imaging in EMPD are needed.

Methicillin resistant Staphylococcus aureus colonization in pigs and pig farmers

Methicillin resistant Staphylococcus aureus (MRSA) colonization has recently been identified in pigs and people that work with pigs, raising concerns about the role of pigs as reservoirs of MRSA for human infection. The objectives of this study were to evaluate the prevalence of MRSA colonization in pigs and pig farmers in Ontario, Canada and to characterize MRSA strains. Nasal and rectal swabs were collected from 285 pigs from three different age groups from 20 pig farms. Nasal swabs were collected from farm personnel and a brief questionnaire was also administered. The prevalence of MRSA colonization in farms was 45% (9/20) whereas the prevalence in pigs was 24.9% (71/285). There was no difference in MRSA colonization between age groups. The prevalence of MRSA colonization in pig farmers was 20% (5/25). There was a correlation between the presence of MRSA in pigs and humans on farms (P value=0.001). The results of spa typing revealed the predominant strain in pigs and humans was eGenomics spa type 539 (Ridom t034, clonal complex 398) which accounted for 59.2% of isolates and has been reported in pigs in Europe. A common human epidemic clone, CMRSA-2 (USA100, clonal complex 5) was also found in both pigs and pig personnel. Indistinguishable strains were found in pigs and pig personnel on all five farms with a colonized human. This study demonstrates that MRSA is common in pigs in Ontario, Canada, and provides further support to concerns about transmission of MRSA between pigs and humans.

An anomaly in the isotopomer shift of the hyperfine spectrum of LiI

A high-precision examination of the hyperfine spectrum of 6LiI in comparison with 7LiI shows a shift in the iodine nuclear electric quadrupole moment that cannot be accounted for by a model in which the electric field gradient at the iodine site is assumed to depend only upon the internuclear distance between Li and I. The other hyperfine interactions are consistent between the two isotopomers, including the previously reported electric hexadecapole interaction of the iodine nucleus.

Western blot analysis of serological response in Helicobacter pylori in acid peptic diseases

A prospective study was undertaken in 70 patients presenting with acid peptic disease with the objective of characterising the serological response to Helicobacter pylori and finding antigens specific for the serodiagnosis of H. pylori infection. H. pylori status was assessed by smear microscopy, rapid urease activity, culture and histopathology of endoscopic gastric antral biopsy specimens. Serological characterisation was carried out by using western blotting of various antigenic components of H. pylori and subsequent enzymatic detection of antibodies against them. Four reactive bands in the molecular weight range of 45-65 kDa were present in all subjects irrespective of H. pylori status. Four to six immunoreactive bands in the molecular weight range of 21-45 kDa were found only in patients with positive H. pylori status and histopathologically proven gastritis. These immunoreactive components may be valuable in specific immunodiagnosis of H. pylori infection.

Strategies for purification of four reproductive hormones from the same batch of buffalo (Bubalus bubalis) pituitaries

The occurrence of different reproductive hormones like LH, FSH, TSH and prolactin, in different side fractions obtained during the extraction of buffalo pituitary glands either by the procedure of Papkoff et al. [Arch Biochem Biophys, 111 (1965) 431] or by that of Ellis [Endocrinology, 69 (1961) 554], was examined with the aid of antisera to respective heterologous hormones as well as bio-assays. Thus in the procedure of Papkoff et al., the SP-Sephadex fractions could be taken for purification of LH and TSH, while the acid pellet yielded prolactin. Further it was shown that 50% (NH4)2SO4 could be directly size fractionated and following cation exchange chromatography yields LH and TSH. FSH could be purified from 80% ammonium sulphate pellet. In another protocol of Ellis, differential extraction and chromatographic separation yielded all the four reproductive hormones. Some of the physico-chemical and immunobiological characteristics of these hormones are described.

Enzyme linked immunosorbent assay & indirect fluorescence assay for rapid diagnosis of Bacteroides fragilis infections

Antibodies for B. fragilis (NCTC 9343) were detected in sera of 121 patients and 37 controls using four methods viz., enzyme linked immunosorbent assay (ELISA), indirect fluorescence test (JFA), countercurrent immunoelectrophoresis (CIE) and indirect haemagglutination test (IHA). Of 121 patients, 57 were culture positive for B. fragilis, 38 positive for anaerobes other than B. fragilis and 26 were negative for anaerobes. In the B. fragilis culture positive group, antibodies to B. fragilis were positive in 82.5, 84.2, 85.90 and 91.2 per cent patients by CIE, ELISA, IHA and IFA respectively. In B. fragilis positive patients IFA was more sensitive than IHA, which for other groups IHA was found to be more sensitive than IFA. When all groups were taken together IHA was found more sensitive than IFA. ELISA and IFA tests are recommended for rapid serological diagnosis of B. fragilis infections, where facilities for these tests are not available, CIE and IHA could be done. Cross reactivity with other Gram negative anaerobic and aerobic bacteria should be kept in mind since seropositivity varied for B. fragilis (82-91%). In infections with microbes other than B. fragilis seropositivity varied between 23.7 to 63.2 per cent and in patients having cultures sterile or positive for other organisms seropositivity was 30.8 to 42.3 per cent. This nonspecificity could be due to other antigens that cross react between B. fragilis and other anaerobes and aerobes or the use of an antigen lacking high purity.