Global, regional, and national burden of neurological disorders, 1990-2016:A systematic analysis for the Global Burden of Disease Study 2016

BACKGROUND: Neurological disorders are increasingly recognised as major causes of death and disability worldwide. The aim of this analysis from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2016 is to provide the most comprehensive and up-to-date estimates of the global, regional, and national burden from neurological disorders.METHODS: We estimated prevalence, incidence, deaths, and disability-adjusted life-years (DALYs; the sum of years of life lost [YLLs] and years lived with disability [YLDs]) by age and sex for 15 neurological disorder categories (tetanus, meningitis, encephalitis, stroke, brain and other CNS cancers, traumatic brain injury, spinal cord injury, Alzheimer's disease and other dementias, Parkinson's disease, multiple sclerosis, motor neuron diseases, idiopathic epilepsy, migraine, tension-type headache, and a residual category for other less common neurological disorders) in 195 countries from 1990 to 2016. DisMod-MR 2.1, a Bayesian meta-regression tool, was the main method of estimation of prevalence and incidence, and the Cause of Death Ensemble model (CODEm) was used for mortality estimation. We quantified the contribution of 84 risks and combinations of risk to the disease estimates for the 15 neurological disorder categories using the GBD comparative risk assessment approach.FINDINGS: Globally, in 2016, neurological disorders were the leading cause of DALYs (276 million [95% UI 247-308]) and second leading cause of deaths (9·0 million [8·8-9·4]). The absolute number of deaths and DALYs from all neurological disorders combined increased (deaths by 39% [34-44] and DALYs by 15% [9-21]) whereas their age-standardised rates decreased (deaths by 28% [26-30] and DALYs by 27% [24-31]) between 1990 and 2016. The only neurological disorders that had a decrease in rates and absolute numbers of deaths and DALYs were tetanus, meningitis, and encephalitis. The four largest contributors of neurological DALYs were stroke (42·2% [38·6-46·1]), migraine (16·3% [11·7-20·8]), Alzheimer's and other dementias (10·4% [9·0-12·1]), and meningitis (7·9% [6·6-10·4]). For the combined neurological disorders, age-standardised DALY rates were significantly higher in males than in females (male-to-female ratio 1·12 [1·05-1·20]), but migraine, multiple sclerosis, and tension-type headache were more common and caused more burden in females, with male-to-female ratios of less than 0·7. The 84 risks quantified in GBD explain less than 10% of neurological disorder DALY burdens, except stroke, for which 88·8% (86·5-90·9) of DALYs are attributable to risk factors, and to a lesser extent Alzheimer's disease and other dementias (22·3% [11·8-35·1] of DALYs are risk attributable) and idiopathic epilepsy (14·1% [10·8-17·5] of DALYs are risk attributable).INTERPRETATION: Globally, the burden of neurological disorders, as measured by the absolute number of DALYs, continues to increase. As populations are growing and ageing, and the prevalence of major disabling neurological disorders steeply increases with age, governments will face increasing demand for treatment, rehabilitation, and support services for neurological disorders. The scarcity of established modifiable risks for most of the neurological burden demonstrates that new knowledge is required to develop effective prevention and treatment strategies.FUNDING: Bill &amp; Melinda Gates Foundation.</p

The Burden of Tick-Borne Encephalitis in Disability-Adjusted Life Years (DALYs) for Slovenia

BACKGROUND:Tick-borne encephalitis (TBE) presents an increasing burden in many parts of Europe, Asian Russia, Siberia, Asian former USSR and Far East. Incidence can be considered as one way to express the burden. A more comprehensive measure concerns disability-adjusted life years (DALYs), better characterizing the full burden of TBE. TBE burden in DALYs has not yet been estimated, nor has it been specified by the Global Burden of Disease (GBD) studies. OBJECTIVE:The purpose of the present study is to estimate the burden of TBE in Slovenia, expressed in DALYs, both from the population and individual perspectives. We discuss the impact of TBE burden on public health and potential strategies to reduce this burden in Slovenia. METHODS:The burden of TBE is estimated by using the updated DALYs' methodology first introduced in the GBD project. The DALYs᾽ calculations are based on the health outcomes of the natural course of the disease being modelled. Corrections for under-reporting and under-ascertainment are applied. The impact of uncertainty in parameters in the model was assessed using sensitivity analyses. RESULTS:From the population perspective, total DALYs amount to 3,450 (167.8 per 100,000 population), while from the individual perspective they amount to 3.1 per case in 2011. Notably, the consequences of TBE present a larger burden than TBE itself. CONCLUSIONS:TBE presents a relatively high burden expressed in DALYs compared with estimates for other infectious diseases from the GBD 2010 study for Slovenia. Raising awareness and increasing vaccination coverage are needed to reduce TBE and its consequences

Effect of breastfeeding promotion interventions on cost-effectiveness of rotavirus immunization in Indonesia

BACKGROUND: Rotavirus infection has been reported to be responsible for the majority of severe diarrhea in children under-5-years-old in Indonesia. Breast milk is considered to give protection against rotavirus infection. Increasing breastfeeding promotion programs could be an alternative target to reduce the incidence of rotavirus diarrhea. This study aims to investigate the effect of breastfeeding promotion interventions on cost-effectiveness of rotavirus immunization in Indonesia, focusing on breastfeeding education and support interventions.METHODS: An age-structured cohort model was developed for the 2011 Indonesia birth cohort. We compared four interventions in scenarios: (i) base-case (I₀) reflecting the current situation for the population of under-5-years-old, (ii) with an additional breastfeeding education intervention (I₁), (iii) with a support intervention on initiation and duration (I₂) and (iv) with both of these two interventions combined (I₃). The model applied a 5-years time horizon, with 1 month analytical cycles for children less than 1 year of age and annually thereafter. Monte Carlo simulations were used to examine the economic acceptability and affordability of rotavirus vaccination.RESULTS: Rotavirus immunization would effectively reduce severe cases of rotavirus during the first 5 years of a child's life even assuming various breastfeeding promotion interventions. The total yearly vaccine cost would amount to US$64 million under the market vaccine price. Cost-effectiveness would increase to US$ 153 per quality-adjusted-life-year (societal perspective) with an optimal breastfeeding promotion intervention. Obviously, this is much lower than the 2011 Gross Domestic Product (GDP) per capita of US$ 3,495. Affordability results showed that at the market vaccine price, rotavirus vaccination could be affordable for the Indonesian health system.CONCLUSIONS: Rotavirus immunization would be a highly cost-effective public health intervention for Indonesia even under various breastfeeding promotion interventions based on the WHO's criteria for cost-effectiveness in universal immunization.</p

Predictors of Health Utility in Relapsing-Remitting and Secondary-Progressive Multiple Sclerosis:Implications for Future Economic Models of Disease-Modifying Therapies

Background Decision-analytic models used in economic evaluations of disease-modifying therapies for relapsing-remitting multiple sclerosis (RRMS) have characterized disease progression and accrue quality-adjusted life-years from utility values based on the Expanded Disability Status Scale (EDSS), the occurrence of relapses, and progression to secondary-progressive multiple sclerosis (SPMS). The EDSS, used to characterize disability progression, has several limitations. If the EDSS is the only disability measure used in economic evaluations, the long-term clinical and economic implications of disease-modifying therapies may not be properly assessed. Objective The objective of this study was to explore if supplementary disability measures including the Timed 25-Foot Walk (T25FW), 9-Hole Peg Test (9HPT), and Paced Auditory Serial Addition Test (PASAT) significantly contribute additional information on health utility in RRMS and SPMS otherwise not captured by the EDSS and relapses and, therefore, should be considered in future economic evaluations of disease-modifying therapies. Methods Short-Form Six-Dimension utility scores were derived from the RAND 36-Item Health Survey 1.0 individual-level data available in the Multiple Sclerosis Outcome Assessment Consortium (MSOAC) Placebo Database. Repeated-measures mixed-effects models were conducted to estimate the effects of EDSS, T25FW, 9HPT (dominant and non-dominant hand), PASAT, and relapses on changes in utility over time, controlling for demographics. Results A higher level of EDSS, longer time to complete the T25FW test, and a recent relapse were significant predictors of lower utility in people with RRMS and SPMS. 9HPT and PASAT were not significant predictors. Conclusions This study suggests that in addition to EDSS and recent relapses, T25FW significantly predicts utility in RRMS and SPMS. These findings support the use of T25FW to supplement the EDSS and the occurrence of relapses to characterize the course of disease progression and to more accurately accrue quality-adjusted life-years in future economic evaluations of disease-modifying therapies for the treatment of RRMS.</p

Mortality, morbidity, and hospitalisations due to influenza lower respiratory tract infections, 2017:an analysis for the Global Burden of Disease Study 2017

BACKGROUND: Although the burden of influenza is often discussed in the context of historical pandemics and the threat of future pandemics, every year a substantial burden of lower respiratory tract infections (LRTIs) and other respiratory conditions (like chronic obstructive pulmonary disease) are attributable to seasonal influenza. The Global Burden of Disease Study (GBD) 2017 is a systematic scientific effort to quantify the health loss associated with a comprehensive set of diseases and disabilities. In this Article, we focus on LRTIs that can be attributed to influenza.METHODS: We modelled the LRTI incidence, hospitalisations, and mortality attributable to influenza for every country and selected subnational locations by age and year from 1990 to 2017 as part of GBD 2017. We used a counterfactual approach that first estimated the LRTI incidence, hospitalisations, and mortality and then attributed a fraction of those outcomes to influenza.FINDINGS: Influenza LRTI was responsible for an estimated 145 000 (95% uncertainty interval [UI] 99 000-200 000) deaths among all ages in 2017. The influenza LRTI mortality rate was highest among adults older than 70 years (16·4 deaths per 100 000 [95% UI 11·6-21·9]), and the highest rate among all ages was in eastern Europe (5·2 per 100 000 population [95% UI 3·5-7·2]). We estimated that influenza LRTIs accounted for 9 459 000 (95% UI 3 709 000-22 935 000) hospitalisations due to LRTIs and 81 536 000 hospital days (24 330 000-259 851 000). We estimated that 11·5% (95% UI 10·0-12·9) of LRTI episodes were attributable to influenza, corresponding to 54 481 000 (38 465 000-73 864 000) episodes and 8 172 000 severe episodes (5 000 000-13 296 000).INTERPRETATION: This comprehensive assessment of the burden of influenza LRTIs shows the substantial annual effect of influenza on global health. Although preparedness planning will be important for potential pandemics, health loss due to seasonal influenza LRTIs should not be overlooked, and vaccine use should be considered. Efforts to improve influenza prevention measures are needed.FUNDING: Bill &amp; Melinda Gates Foundation.</p

Global, regional, and national burden of stroke, 1990-2016:A systematic analysis for the Global Burden of Disease Study 2016

BACKGROUND: Stroke is a leading cause of mortality and disability worldwide and the economic costs of treatment and post-stroke care are substantial. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) provides a systematic, comparable method of quantifying health loss by disease, age, sex, year, and location to provide information to health systems and policy makers on more than 300 causes of disease and injury, including stroke. The results presented here are the estimates of burden due to overall stroke and ischaemic and haemorrhagic stroke from GBD 2016.METHODS: We report estimates and corresponding uncertainty intervals (UIs), from 1990 to 2016, for incidence, prevalence, deaths, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs). DALYs were generated by summing YLLs and YLDs. Cause-specific mortality was estimated using an ensemble modelling process with vital registration and verbal autopsy data as inputs. Non-fatal estimates were generated using Bayesian meta-regression incorporating data from registries, scientific literature, administrative records, and surveys. The Socio-demographic Index (SDI), a summary indicator generated using educational attainment, lagged distributed income, and total fertility rate, was used to group countries into quintiles.FINDINGS: In 2016, there were 5·5 million (95% UI 5·3 to 5·7) deaths and 116·4 million (111·4 to 121·4) DALYs due to stroke. The global age-standardised mortality rate decreased by 36·2% (-39·3 to -33·6) from 1990 to 2016, with decreases in all SDI quintiles. Over the same period, the global age-standardised DALY rate declined by 34·2% (-37·2 to -31·5), also with decreases in all SDI quintiles. There were 13·7 million (12·7 to 14·7) new stroke cases in 2016. Global age-standardised incidence declined by 8·1% (-10·7 to -5·5) from 1990 to 2016 and decreased in all SDI quintiles except the middle SDI group. There were 80·1 million (74·1 to 86·3) prevalent cases of stroke globally in 2016; 41·1 million (38·0 to 44·3) in women and 39·0 million (36·1 to 42·1) in men.INTERPRETATION: Although age-standardised mortality rates have decreased sharply from 1990 to 2016, the decrease in age-standardised incidence has been less steep, indicating that the burden of stroke is likely to remain high. Planned updates to future GBD iterations include generating separate estimates for subarachnoid haemorrhage and intracerebral haemorrhage, generating estimates of transient ischaemic attack, and including atrial fibrillation as a risk factor.FUNDING: Bill &amp; Melinda Gates Foundation.</p