Accounting for multimorbidity can affect the estimation of the Burden of Disease: a comparison of approaches

The burden of mental disorders in Mexico, 1990-2019: Mental and neurological disorders, substance use, suicides, and related somatic disorders

INTRODUCTION

Mental, neurological, substance use, suicide, and related somatic disorders (MNSS, for the Spanish acronym) have a negative impact on the quality-of-life of people and the Mexican economy, but updated information is lacking. The objective of this work is to analyze the disability adjusted life years (DALYs) of the MNSS in Mexico by sex, age, state, and degree of marginalization between 1990 and 2019.

METHODS

The data and methodology of the «Global Burden of Disease Group» (GBD) are used. The GBD calculates DALYs as the sum of two components: years of life lost due to premature mortality (YLL) and years lived with disability (YLD). Likewise, the data on the degree of marginalization from the National Population Council in Mexico are used.

RESULTS

MNSS represented 16.3% of the disease burden in the Mexican population in 2019. The trend of the age-standardized rates of DALYs of the MNSS has increased little from 1990 to 2019. The highest increase has been for women. Mental (depression) and neurological (headache) disorders contribute the most to the disease burden among MNSS. In the interior of the country, Baja California Sur presented the highest increase in the period.

DISCUSSION

The results show a complex panorama of the MNSS and its subtypes by sex, age groups and territory. More resources are needed to improve mental health care.

Economic Burden of Sanfilippo Syndrome in the United States

Introduction

Sanfilippo syndrome is a rare disease and fatal genetic disorder with no FDA-approved treatment in the United States (US), and no comprehensive assessment of economic disease burden is available.

Objectives

To develop a model to estimate the economic burden associated with Sanfilippo syndrome in the US using direct costs, indirect costs and valued intangibles (disability-adjusted life years, or DALYs) from 2023 onward.

Design and Setting

A multistage comorbidity model was generated based on Sanfilippo syndrome symptoms, and disability weights from the 2010 Global Burden of Disease Study. Attributable increase in caregiver mental health burden were estimated using data from the CDC National Comorbidity Survey and retrospective studies on caregiver burden. Direct costs were approximated from the 2019 EveryLife Foundation survey, and indirect costs were estimated from Federal income data. Monetary valuations were adjusted to USD 2023 and given a 3% discount rate from 2023 onward.

Main Outcome Measures

Incidence of Sanfilippo syndrome was calculated for each year, and year-over-year DALYs due to patient years lived with disability (YLDs) and years life lost (YLLs) were calculated by comparing to the health-adjusted life expectancy (HALE) in the US. Direct and indirect costs were calculated for each simulated patient from onset of symptoms to death.

Results

From 2023-2043, overall economic burden in the US attributable to Sanfilippo syndrome was estimated to be $2.04 billion USD present value (2023) with current standard of care. The burden to individual families exceeded $8 million present value from time of birth per child born with Sanfilippo syndrome.

Conclusion

Sanfilippo syndrome is a rare lysosomal storage disease, however the severe burden associated with the disease for individual families demonstrates a considerable cumulative impact. Our model represents the first disease burden value estimate associated with Sanfilippo syndrome, and underscores the substantial morbidity and mortality burden of Sanfilippo syndrome.

A novel comorbidity index in Italy based on diseases detected by the surveillance system PASSI and the Global Burden of Diseases disability weights

BACKGROUND

Understanding comorbidity and its burden characteristics is essential for policymakers and healthcare providers to allocate resources accordingly. However, several definitions of comorbidity burden can be found in the literature. The main reason for these differences lies in the available information about the analyzed diseases (i.e., the target population studied), how to define the burden of diseases, and how to aggregate the occurrence of the detected health conditions.

METHODS

In this manuscript, we focus on data from the Italian surveillance system PASSI, proposing an index of comorbidity burden based on the disability weights from the Global Burden of Disease (GBD) project. We then analyzed the co-presence of ten non-communicable diseases, weighting their burden thanks to the GBD disability weights extracted by a multi-step procedure. The first step selects a set of GBD weights for each disease detected in PASSI using text mining. The second step utilizes an additional variable from PASSI (i.e., the perceived health variable) to associate a single disability weight for each disease detected in PASSI. Finally, the disability weights are combined to form the comorbidity burden index using three approaches common in the literature.

RESULTS

The comorbidity index (i.e., combined disability weights) proposed allows an exploration of the magnitude of the comorbidity burden in several Italian sub-populations characterized by different socioeconomic characteristics. Thanks to that, we noted that the level of comorbidity burden is greater in the sub-population characterized by low educational qualifications and economic difficulties than in the rich sub-population characterized by a high level of education. In addition, we found no substantial differences in terms of predictive values of comorbidity burden adopting different approaches in combining the disability weights (i.e., additive, maximum, and multiplicative approaches), making the Italian comorbidity index proposed quite robust and general.

Multimorbidity Patterns in the Urban Population in Poland

A number of studies have been conducted on multimorbidity; however, there are different patterns in various countries, ethnicities and social groups. The aim of this study is to estimate the prevalence of multimorbidity (physical diseases) in the urban population in Poland. In this population-based study, we examined multimorbidity stratified by sex, age, educational attainment and professional activity. Sixty-seven conditions were identified based on self-reported history (known conditions) and completed examinations (unknown conditions). Among the overall individuals aged 20-80 years, 1422 (88.2%) of the total 1612 individuals, 787 (88.9%) of 885 women and 635 (87.3%) of 727 men were diagnosed with at least two chronic conditions. On average, 5.25 ± 3.5 conditions occurred in the study population. The number of diagnosed conditions per individual increased with age and decreased with higher educational levels, with differing pathways in women and men. Women showed a higher number of conditions than men in the same age groups and educational levels. Only among students, the level of multimorbidity was lower in women than in men. In the other occupational activity categories, it was already higher in women. The level of multimorbidity in employed and unemployed individuals in a particular sex cluster was similar. We identified a high prevalence of multimorbidity in the urban population in Poland varying by age, sex, education attainment and professional activity. Our work may help in the selection of appropriate screening tests based on age, sex and educational attainment in order to recognise multimorbidity based on both known and unknown conditions. Ultimately, it may impact clinical practice, service delivery and study design.

The health and economic burden of musculoskeletal disorders in Belgium from 2013 to 2018

INTRODUCTION

Low back pain (LBP), neck pain (NKP), osteoarthritis (OST) and rheumatoid arthritis (RHE) are among the musculoskeletal (MSK) disorders causing the greatest disability in terms of Years Lived with Disability. The current study aims to analyze the health and economic impact of these MSK disorders in Belgium, providing a summary of morbidity and mortality outcomes from 2013 to 2018, as well as direct and indirect costs from 2013 to 2017.

METHODS

The health burden of LBP, NKP, OST and RHE in Belgium from 2013 to 2018 was summarized in terms of prevalence and disability-adjusted life years (DALY) using data from the Belgian health interview surveys (BHIS), the INTEGO database (Belgian registration network for general practitioners) and the Global Burden of Diseases study 2019. The economic burden included estimates of direct medical costs and indirect costs, measured by cost of work absenteeism. For this purpose, data of the respondents to the BHIS-2013 were linked with the national health insurance data (intermutualistic agency [IMA] database) 2013-2017.

RESULTS

In 2018, 2.5 million Belgians were affected by at least one MSK disorder. OST represented the disorder with the highest number of cases for both men and women, followed by LBP. In the same year, MSK disorders contributed to a total of 180,746 DALYs for female and 116,063 DALYs for men. LBP appeared to be the largest contributor to the health burden of MSK. Having at least one MSK disorder costed on average 3 billion € in medical expenses and 2 billion € in indirect costs per year, with LBP being the most costly.

CONCLUSION

MSK disorders represent a major health and economic burden in Belgium. As their burden will probably continue to increase in the future, acting on the risk factors associated to these disorders is crucial to mitigate both the health and economic burden.

Long-term evolution of comorbidities and their disease burden in individuals with and without HIV as they age: analysis of the prospective AGE(h)IV cohort study

BACKGROUND

People with HIV generally have more ageing-associated comorbidities than those without HIV. We aimed to establish whether the difference in comorbidities and their disease burden changes with ageing.

METHODS

In this prospective, longitudinal cohort study, we assessed comorbidities commonly associated with ageing every 2 years in 596 HIV-positive and 550 HIV-negative participants. HIV-positive participants were recruited from the HIV outpatient clinic of the Amsterdam University Medical Centres (Amsterdam, Netherlands). HIV-negative participants were recruited from the sexual health clinic and the Amsterdam Cohort Studies at the Public Health Service of Amsterdam (Amsterdam, Netherlands). Inclusion criteria were participants aged 45 years or older and, for HIV-negative participants, a documented HIV-negative antibody test. The mean number of comorbidities present over time was compared between groups by use of Poisson regression, accounting for dropout and death through joint survival models. Mean disability-adjusted life-years (DALYs) accrued during 2-year intervals were compared between groups by use of an exponential hurdle model.

FINDINGS

Between Oct 29, 2010, and Oct 9, 2012, participants were enrolled and then prospectively followed up until their last visit before Oct 1, 2018. 1146 participants were followed up for a median 5·9 years (IQR 5·7-6·0), during which 231 participants (20·2%) dropped out: 145 (24·3%) of 596 HIV-positive and 86 (15·6%) of 550 HIV-negative. 38 (3·3%) of 1146 participants died: 31 (5·2%) of 596 HIV-positive and seven (1·3%) of 550 HIV-negative. 24 HIV-positive and two HIV-negative participants died from ageing-associated comorbidities. 15 HIV-positive participants versus one HIV-negative participant died from non-AIDS malignancies. At inclusion, mean number of comorbidities was higher in HIV-positive participants (0·65) than in HIV-negative participants (0·32; p<0·0001). Mean number of comorbidities increased at similar rates over time: rate ratio (RR) per year for HIV-positive participants 1·04 (95% CI 1·00-1·08), RR per year for HIV-negative participants 1·05 (1·01-1·08; p_interaction=0·78). Number of comorbidities was associated with an increased risk of death (hazard ratio 3·33 per additional comorbidity, 95% CI 2·27-4·88; p<0·0001). HIV-positive participants had higher increases in mean DALYs than HIV-negative participants (0·209 per year, 95% CI 0·162-0·256 vs 0·091 per year, 0·025-0·157; p_interaction=0·0045). This difference was reduced when deaths were excluded in establishing DALYs (0·127, 0·083-0·171 vs 0·066, 0·005-0·127; p_interaction =0·11).

INTERPRETATION

The larger comorbidity prevalence in HIV-positive participants aged 50-55 years on effective antiretroviral treatment than in HIV-negative participants increased similarly as participants aged and was associated with an increased risk of death, particularly of non-AIDS malignancies. Our findings reinforce the need for strategies to optimise prevention, screening, and early intervention.

FUNDING

Netherlands Organization for Health Research and Development, Aidsfonds, Gilead Sciences, ViiV Healthcare, Janssen Pharmaceuticals, and Merck & Co.

TRANSLATION

For the Dutch translation of the abstract see Supplementary Materials section.

Cervical Total Disc Replacement and Anterior Cervical Discectomy and Fusion: Comparison of 30-Day Population Comorbidities and Perioperative Complications Using 6 Years of American College of Surgeons National Surgical Quality Improvement Program Participant Use File Data

OBJECTIVE

American College of Surgeons National Surgical Quality Improvement Program Participant Use File data from 2014 through 2019 were used to compare 1- and 2-level anterior cervical discectomy and fusion (ACDF) and cervical total disc replacement (cTDR) with respect to: patient demographics, comorbidities, adverse events, and 30-day morbidity rates.

METHODS

One- and 2-level ACDF and cTDR patients were identified by current procedural terminology codes. Demographics, comorbidities, and adverse events were summarized. Unmatched cohorts were compared using Wilcoxon Rank Sum test for continuous variables, Pearson χ² test for categorical variables, and 30-day morbidity using inverse probability of treatment weighted log-binomial regression.

RESULTS

American College of Surgeons National Surgical Quality Improvement Program 2014 through 2019 Participant Use File datasets represent 4,862,497 unique patients, identifying 13,347 1-level, 6933 2-level ACDF, 3114 1-level, and 862 2-level cTDR patient cohorts. Statistically significant differences between cohorts are extensive: age, sex, race, admission status, patient origin, discharge disposition, emergent surgery, surgical specialty, American Society of Anesthesiologists classification, wound class, operative time, hospital LOS, BMI, functional status, smoking, diabetes, dyspnea, chronic obstructive pulmonary disease, congestive heart failure, hypertension, renal failure, dialysis, cancer, steroid use, anemia, bleeding disorders, systemic sepsis, and number of concurrent comorbid conditions. Inverse probability of treatment weighted log-binomial models, demonstrated increased risk of deep venous thrombosis/thrombophlebitis, pulmonary embolism, deep incisional surgical site infection, pneumonia, and unplanned return to operating room associated with ACDF while increased risk of cerebral vascular accident/stroke with neurological deficit and myocardial infarction associated with cTDR. The composite complications outcome favors cTDR over ACDF for 30-day morbidity. No mortalities occurred within the cTDR cohort.

CONCLUSIONS

Adjusting for demographics and comorbidities; ACDF has a higher average risk of adverse event. When ACDF and cTDR are equipoise, consideration for cTDR may be indicated in populations with higher rates of comorbid conditions.

Model-based estimation of burden of COVID-19 with disability-adjusted life years and value of statistical life in West Bengal, India

OBJECTIVES

The COVID-19 pandemic has posed unprecedented challenges to health systems and populations, particularly in India. Comprehensive, population-level studies of the burden of disease could inform planning, preparedness and policy, but are lacking in India. In West Bengal, India, we conducted a detailed analysis of the burden caused by COVID-19 from its onset to 7 January 2022.

SETTING

Open-access, population-level and administrative data sets for West Bengal were used.

PRIMARY AND SECONDARY OUTCOME MEASURES

Disability-adjusted life years (DALYs), years of potential productive life lost (YPPLL), cost of productivity lost (CPL: premature mortality and absenteeism), years of potential life lost (YPLL), premature years of potential life lost, working years of potential life lost (WYPLL) and value of statistical life (VSL) were estimated across scenarios (21 for DALY and 3 each for YPLL and VSL) to evaluate the effects of different factors.

RESULTS

COVID-19 had a higher impact on the elderly population with 90.2% of deaths arising from people aged above 45. In males and females, respectively, DALYs were 190 568.1 and 117 310.0 years, YPPLL of the productive population was 28 714.7 and 16 355.4 years, CPL due to premature mortality was INR3 198 259 615.6 and INR583 397 335.1 and CPL due to morbidity was INR2 505 568 048.4 and INR763 720 886.1. For males and females, YPLL ranged from 189 103.2 to 272 787.5 years and 117 925.5 to 169 712.0 years for lower to higher age limits, and WYPLL was 54 333.9 and 30 942.2 years. VSL (INR million) for the lower, midpoint and upper life expectancies was 883 330.8; 882 936.4; and 880 631.3, respectively. Vaccination was associated with reduced mortality.

CONCLUSIONS

The losses incurred due to COVID-19 in terms of the computed estimates in West Bengal revealed a disproportionately higher impact on the elderly and males. Analysis of various age-gender subgroups enhances localised and targeted policymaking to minimise the losses for future pandemics.

Association of Parental Cardiovascular Health With Disability-Adjusted Life Years in the Offspring: Results From the Framingham Heart Study

BACKGROUND

Disability-adjusted life years (DALYs) are used to evaluate the relative burden of diseases in populations to help set prevention or treatment priorities. The impact of parental cardiovascular health (CVH) on healthy life years lost from cardiovascular disease (CVD) in adult offspring is unknown. We compared parent-offspring CVD DALYs trends over the life course and examined the association of parental CVH with offspring CVD DALYs.

METHODS

Using data from the Framingham Heart Study, 4814 offspring-mother-father trios were matched for age at selected baseline exams. CVH score was computed from the number of CVH metrics attained at recommended levels: poor (0-2), intermediate (3-4), and ideal (5-7). CVD DALYs were defined as the sum of years of life lost and years lived with CVD. Age-sex-standardized life expectancy and disability weights were derived from the actuarial life tables and Global Burden of Disease study, respectively. Multivariable-adjusted linear regression was used to investigate the association of parental CVH with offspring CVD DALYs.

RESULTS

Over an equal 47-year follow-up, parents lost nearly twice the number of CVD DALYs compared to their offspring (23 234 versus 12 217). However, age-adjusted CVD DALYs were higher at younger ages and similar along the life course for parents and offspring. One-unit increase in parental CVH was associated with 5 healthy life months saved in offspring. Offspring of mothers with ideal versus poor CVH had 3 healthy life years saved (β=-3.0 DALYs [95% CI, -5.6 to -0.3]). No statistically significant association was found between paternal CVH categories and offspring CVD DALYs.

CONCLUSIONS

Higher maternal and paternal CVH were associated with increased healthy life years in offspring; however, the association was strongest between mothers and offspring. Investment in CVH promotion along the life course has the potential to reduce the burden of CVD in the current and future generation of adults.

The Burden of Disease in Germany at the National and Regional Level

BACKGROUND

.Summary measures such as disability-adjusted life years (DALY) are becoming increasingly important for the standardized assessment of the burden of disease due to death and disability. The BURDEN 2020 pilot project was designed as an independent burden-of-disease study for Germany, which was based on nationwide data, but which also yielded regional estimates.

METHODS

DALY is defined as the sum of years of life lost due to death (YLL) and years lived with disability (YLD). YLL is the difference between the age at death due to disease and the remaining life expectancy at this age, while YLD quantifies the number of years individuals have spent with health impairments. Data are derived mainly from causes of death statistics, population health surveys, and claims data from health insurers.

RESULTS

In 2017, there were approximately 12 million DALY in Germany, or 14 584 DALY per 100 000 inhabitants. Conditions which caused the greatest number of DALY were coronary heart disease (2321 DALY), low back pain (1735 DALY), and lung cancer (1197 DALY). Headache and dementia accounted for a greater disease burden in women than in men, while lung cancer and alcohol use disorders accounted for a greater disease burden in men than in women. Pain disorders and alcohol use disorders were the leading causes of DALY among young adults of both sexes. The disease burden rose with age for some diseases, including cardiovascular diseases, dementia, and diabetes mellitus. For some diseases and conditions, the disease burden varied by geographical region.

CONCLUSION

The results indicate a need for age- and sex-specific prevention and for differing interventions according to geographic region. Burden of disease studies yield comprehensive population health surveillance data and are a useful aid to decision-making in health policy.

Disability-adjusted life years associated with chronic comorbidities among people living with and without HIV: Estimating health burden in British Columbia, Canada

Life span of people living with HIV (PLWH) has increased dramatically with the advent of modern antiretroviral therapy. As a result, comorbidities have emerged as a significant concern in this population. To describe the burden of chronic comorbidities among PLWH and HIV-negative individuals in British Columbia (BC), Canada, we estimated disability-adjusted life years (DALYs) related to these comorbidities. Based on a population-based cohort in BC, antiretroviral-treated adult PLWH and 1:4 age-sex-matched HIV-negative controls were followed for ≥1 year during 2001-2012. DALYs combined years of life lost to premature mortality (YLLs) and due to disability (YLDs), and were estimated following the Global Burden of Diseases' approaches. DALYs associated with non-AIDS-defining cancers, diabetes, osteoarthritis, hypertension, dementia, cardiovascular (CVD), kidney, liver and chronic obstructive pulmonary diseases were each measured for 2008-2012. Among PLWH, DALYs attributed to non-AIDS-related cancers were also estimated for 2013-2020. We observed that at baseline, our matched cohort consisted of 82% males with a median age of 40 years (25th-75th percentiles: 34-47). During 2008-2012, 7042 PLWH and 30,640 HIV-negative individuals were alive, where PLWH experienced a twofold higher DALYs associated with chronic comorbidities (770.2 years/1000 people [95% credible intervals: 710.2, 831.6] vs. 359.0 [336.0, 382.2]). Non-AIDS-defining cancers and CVD contributed the highest DALYs in both populations, driven by YLLs rather than YLDs. Among PLWH, we estimated increasing DALYs attributable to non-AIDS-defining cancers with 91.7 years/1000 people (77.4, 106.0) in 2013 vs. 97.6 (81.0, 115.2) in 2020. In this study, we showed that PLWH experience a disproportionate burden of chronic comorbidities compared to HIV-negative individuals. The observed disparities may relate to differential health behaviors, residual HIV-related inflammation, and ART-related toxicities. As aging shapes future healthcare needs, our findings highlight the need to enhance prevention and management of comorbidities as part of HIV care.

TB morbidity estimates overlook the contribution of post-TB disability: evidence from urban Malawi

INTRODUCTION

Despite growing evidence of the long-term impact of tuberculosis (TB) on quality of life, Global Burden of Disease (GBD) estimates of TB-related disability-adjusted life years (DALYs) do not include post-TB morbidity, and evaluations of TB interventions typically assume treated patients return to pre-TB health. Using primary data, we estimate years of life lost due to disability (YLDs), years of life lost due to premature mortality (YLL) and DALYs associated with post-TB cardiorespiratory morbidity in a low-income country.

METHODS

Adults aged ≥15 years who had successfully completed treatment for drug-sensitive pulmonary TB in Blantyre, Malawi (February 2016-April 2017) were followed-up for 3 years with 6-monthly and 12-monthly study visits. In this secondary analysis, St George's Respiratory Questionnaire data were used to match patients to GBD cardiorespiratory health states and corresponding disability weights (DWs) at each visit. YLDs were calculated for the study period and estimated for remaining lifespan using Malawian life table life expectancies. YLL were estimated using study mortality data and aspirational life expectancies, and post-TB DALYs derived. Data were disaggregated by HIV status and gender.

RESULTS

At treatment completion, 222/403 (55.1%) participants met criteria for a cardiorespiratory DW, decreasing to 15.6% after 3 years, at which point two-thirds of the disability burden was experienced by women. Over 90% of projected lifetime-YLD were concentrated within the most severely affected 20% of survivors. Mean DWs in the 3 years post-treatment were 0.041 (HIV-) and 0.025 (HIV+), and beyond 3 years estimated as 0.025 (HIV-) and 0.010 (HIV+), compared with GBD DWs of 0.408 (HIV+) and 0.333 (HIV-) during active disease. Our results imply that the majority of TB-related morbidity occurs post-treatment.

CONCLUSION

TB-related DALYs are greatly underestimated by overlooking post-TB disability. The total disability burden of TB is likely undervalued by both GBD estimates and economic evaluations of interventions, particularly those aimed at early diagnosis and prevention.

Measuring disability-adjusted life years (DALYs) due to COVID-19 in Scotland, 2020

Background

Disability-adjusted life years (DALYs) combine the impact of morbidity and mortality and can enable comprehensive, and comparable, assessments of direct and indirect health harms due to COVID-19. Our aim was to estimate DALYs directly due to COVID-19 in Scotland, during 2020; and contextualise its population impact relative to other causes of disease and injury.

Methods

National deaths and daily case data were used. Deaths were based on underlying and contributory causes recorded on death certificates. We calculated DALYs based on the COVID-19 consensus model and methods outlined by the European Burden of Disease Network. DALYs were presented as a range, using a sensitivity analysis based on Years of Life Lost estimates using: cause-specific; and COVID-19 related deaths. All COVID-19 estimates were for 2020.

Results

In 2020, estimates of COVID-19 DALYs in Scotland ranged from 96,500 to 108,200. Direct COVID-19 DALYs were substantial enough to be framed as the second leading cause of disease and injury, with only ischaemic heart disease having a larger impact on population health. Mortality contributed 98% of total DALYs.

Conclusions

The direct population health impact of COVID-19 has been very substantial. Despite unprecedented mitigation efforts, COVID-19 developed from a single identified case in early 2020 to a condition with an impact in Scotland second only to ischaemic heart disease. Periodic estimation of DALYs during 2021, and beyond, will provide indications of the impact of DALYs averted due to the national rollout of the vaccination programme and other continued mitigation efforts, although new variants may pose significant challenges.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13690-022-00862-x.

Burden of non-communicable disease studies in Europe: a systematic review of data sources and methodological choices

BACKGROUND

Assessment of disability-adjusted life years (DALYs) resulting from non-communicable diseases (NCDs) requires specific calculation methods and input data. The aims of this study were to (i) identify existing NCD burden of disease (BoD) activities in Europe; (ii) collate information on data sources for mortality and morbidity; and (iii) provide an overview of NCD-specific methods for calculating NCD DALYs.

METHODS

NCD BoD studies were systematically searched in international electronic literature databases and in grey literature. We included all BoD studies that used the DALY metric to quantify the health impact of one or more NCDs in countries belonging to the European Region.

RESULTS

A total of 163 BoD studies were retained: 96 (59%) were single-country or sub-national studies and 67 (41%) considered more than one country. Of the single-country studies, 29 (30%) consisted of secondary analyses using existing Global Burden of Disease (GBD) results. Mortality data were mainly derived (49%) from vital statistics. Morbidity data were frequently (40%) drawn from routine administrative and survey datasets, including disease registries and hospital discharge databases. The majority (60%) of national BoD studies reported mortality corrections. Multimorbidity adjustments were performed in 18% of national BoD studies.

CONCLUSION

The number of national NCD BoD assessments across Europe increased over time, driven by an increase in BoD studies that consisted of secondary data analysis of GBD study findings. Ambiguity in reporting the use of NCD-specific BoD methods underlines the need for reporting guidelines of BoD studies to enhance the transparency of NCD BoD estimates across Europe.

Adjustment for Multimorbidity in Estimations of the Burden of Diseases Using Korean NHIS Data

The current multimorbidity correction method in the Global Burden of Disease studies assumes the independent occurrence of diseases. Those studies use Monte-Carlo simulations to adjust for the presence of multiple disease conditions for all diseases. The present study investigated whether the above-mentioned assumption is reasonable based on the prevalence confirmed from actual data. This study compared multimorbidity-adjusted years of lived with disability (YLD) obtained by Monte-Carlo simulations and multimorbidity-adjusted YLD using multimorbidity prevalence derived from National Health Insurance Service data. The 5 most common diseases by sex and age groups were selected as diseases of interest. No significant differences were found between YLD estimations made using actual data and Monte-Carlo simulations, even though assumptions about the independent occurrence of diseases should be carefully applied. The prevalence was not well reflected according to disease characteristics in those under the age of 30, among whom there was a difference in YLD between the 2 methods. Therefore, when calculating the burden of diseases for Koreans over the age of 30, it is possible to calculate the YLD with correction for multimorbidity through Monte-Carlo simulation, but care should be taken with under-30s. It is useful to apply the efficiency and suitability of calibration for multiplicative methods using Monte-Carlo simulations in research on the domestic disease burden, especially in adults in their 30s and older. Further research should be carried out on multimorbidity correction methodology according to the characteristics of multiple diseases by sex and age.

Estimating the direct Covid-19 disability-adjusted life years impact on the Malta population for the first full year

BACKGROUND

Disability-adjusted life years (DALYs) combine the impact of morbidity and mortality, allowing for comprehensive comparisons of the population. The aim was to estimate the DALYs due to Covid-19 in Malta (March 2020-21) and investigate its impact in relation to other causes of disease at a population level.

METHODS

Mortality and weekly hospital admission data were used to calculate DALYs, based on the European Burden of Disease Network consensus Covid-19 model. Covid-19 infection duration of 14 days was considered. Sensitivity analyses for different morbidity scenarios, including post-acute consequences were presented.

RESULTS

An estimated 70,421 people were infected (with and without symptoms) by Covid-19 in Malta (March 2020-1), out of which 1636 required hospitalisation and 331 deaths, contributing to 5478 DALYs. These DALYs positioned Covid-19 as the fourth leading cause of disease in Malta. Mortality contributed to 95% of DALYs, while post-acute consequences contributed to 60% of morbidity.

CONCLUSIONS

Covid-19 over 1 year has impacted substantially the population health in Malta. Post-acute consequences are the leading morbidity factors that require urgent targeted action to ensure timely multidisciplinary care. It is recommended that DALY estimations in 2021 and beyond are calculated to assess the impact of vaccine roll-out and emergence of new variants.

Estimation of the economic burden of COVID-19 using disability-adjusted life years (DALYs) and productivity losses in Kerala, India: a model-based analysis

OBJECTIVES

From the beginning of the COVID-19 pandemic, clinical practice and research globally have centred on the prevention of transmission and treatment of the disease. The pandemic has had a huge impact on the economy and stressed healthcare systems worldwide. The present study estimates disability-adjusted life years (DALYs), years of potential productive life lost (YPPLL) and cost of productivity lost (CPL) due to premature mortality and absenteeism secondary to COVID-19 in the state of Kerala, India.

SETTING

Details on sociodemographics, incidence, death, quarantine, recovery time, etc were derived from public sources and the Collective for Open Data Distribution-Keralam. The working proportion for 5-year age-gender cohorts and the corresponding life expectancy were obtained from the 2011 Census of India.

PRIMARY AND SECONDARY OUTCOME MEASURES

The impact of the disease was computed through model-based analysis on various age-gender cohorts. Sensitivity analysis was conducted by adjusting six variables across 21 scenarios. We present two estimates, one until 15 November 2020 and later updated to 10 June 2021.

RESULTS

Severity of infection and mortality were higher among the older cohorts, with men being more susceptible than women in most subgroups. DALYs for males and females were 15 954.5 and 8638.4 until 15 November 2020, and 83 853.0 and 56 628.3 until 10 June 2021. The corresponding YPPLL were 1323.57 and 612.31 until 15 November 2020, and 6993.04 and 3811.57 until 10 June 2021, and the CPL (premature mortality) were 263 780 579.94 and 41 836 001.82 until 15 November 2020, and 1 419 557 903.76 and 278 275 495.29 until 10 June 2021.

CONCLUSIONS

Most of the COVID-19 burden was contributed by years of life lost. Losses due to YPPLL were reduced as the impact of COVID-19 infection was lesser among the productive cohorts. The CPL values for individuals aged 40-49 years old were the highest. These estimates provide the data necessary for policymakers to work on reducing the economic burden of COVID-19 in Kerala.

Recommendations to plan a national burden of disease study

Background

The InfAct (Information for Action) project is a European Commission Joint Action on Health Information which has promoted the potential role of burden of disease (BoD) approaches to improve the current European Union-Health Information System (EU-HIS). It has done so by raising awareness of the concept, the methods used to calculate estimates and their potential implications and uses in policymaking. The BoD approach is a systematic and scientific effort to quantify and compare the magnitude of health loss due to different diseases, injuries, and risk factors with estimates produced by demographic characteristics and geographies for specific points in time. Not all countries have the resources to undertake such work, and may therefore start with a more restricted objective, e.g., a limited number of diseases, or the use of simple measures of population health such as disease prevalence or life expectancy. The main objective to develop these recommendations was to facilitate those countries planning to start a national burden of disease study.

Results

These recommendations could be considered as minimum requirements for those countries planning to start a BoD study and includes following elements: (1) Define the objectives of a burden of disease study within the context of your country, (2) Identify, communicate and secure the benefits of performing national burden of disease studies, (3) Secure access to the minimum required data sources, (4) Ensure the minimum required capacity and capability is available to carry out burden of disease study, (5) Establish a clear governance structure for the burden of disease study and stakeholder engagement/involvement, (6) Choose the appropriate methodological approaches and (7) Knowledge translation. These were guided by the results from our survey performed to identify the needs of European countries for BoD studies, a narrative overview from four European countries (Belgium, Germany, The Netherlands and Scotland) and the summary of a comparative study of country health profiles with national health statistics.

Conclusions

These recommendations as minimum requirements would facilitate efforts by those European countries who intend to perform national BoD studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13690-021-00652-x.

Towards a needs-based design of the physical rehabilitation workforce in South Africa: trend analysis [1990-2017] and a 5-year forecasting for the most impactful health conditions based on global burden of disease estimates

BACKGROUND

Rehabilitation can improve function in many people with chronic health conditions. It is important to consider priority conditions requiring rehabilitation, so it can be realistically positioned and costed in national health financing systems like South Africa (SA)'s proposed National Health Insurance (NHI). This paper describes temporal trends of top-ranked conditions on years lived with disability (YLDs) rates in SA, for which physical rehabilitation can ameliorate associated disability.

METHODS

This study is a systematic synthesis of publicly available Global Burden of Disease (GBD) 2017 estimates. The top 11 conditions contributing most to YLDs and for which evidence-based rehabilitation interventions exist were identified. Age-standardized rates per 100,000 and YLDs counts were extracted from 1990 to 2017. Significance of changes in temporal trends was determined using Mann-Kendall trend tests. Best-fit rates of yearly changes were calculated per condition, using GBD estimates (2012-2017), and extrapolated (by imposing the best-fit regression line onto results for each subsequent predicted year) as forecasts (2018-2022).

RESULTS

Trends for YLDs counts per condition year (1990-2017) and forecasted values (2018-2022) showed an overall steady increase for all conditions, except HIV and respiratory conditions. YLDs counts almost doubled from 1990 to 2017, with a 17% predicted increase from 2017 to 2022. The proportionate contribution to YLDs counts reduced over time for all conditions, except HIV. Although age-standardized YLDs rates appear relatively stable over the analyzed periods for all conditions (except HIV, respiratory conditions and type 2 diabetes), trend changes in YLDs rates over 28 years were significant for all conditions, except neonatal (p = 0.855), hearing loss (p = 0.100) and musculoskeletal conditions (p = 0.300). Significant trend decreases were apparent for 4/9 conditions, implying that another 5/9 conditions showed trend increases over 28 years. Predicted all-age prevalence in 2022 suggests relatively large increases for cardiovascular disease and heart failure, and burns, while relative decreases are predicted for fractures and dislocations, stroke, and musculoskeletal conditions.

CONCLUSION

Rehabilitation needs in SA are potentially massive and unmet, highlighting the need for innovative and context-specific rehabilitation that considers current local needs and projected changes. These findings should be considered when designing the NHI and other schemes in SA to ensure human and financial resources are deployed efficiently.

Reflections on key methodological decisions in national burden of disease assessments

BACKGROUND

Summary measures of population health are increasingly used in different public health reporting systems for setting priorities for health care and social service delivery and planning. Disability-adjusted life years (DALYs) are one of the most commonly used health gap summary measures in the field of public health and have become the key metric for quantifying burden of disease (BoD). BoD methodology is, however, complex and highly data demanding, requiring a substantial capacity to apply, which has led to major disparities across researchers and nations in their resources to perform themselves BoD studies and interpret the soundness of available estimates produced by the Global Burden of Disease Study.

METHODS

BoD researchers from the COST Action European Burden of Disease network reflect on the most important methodological choices to be made when estimating DALYs. The paper provides an overview of eleven methodological decisions and challenges drawing on the experiences of countries working with BoD methodology in their own national studies. Each of these steps are briefly described and, where appropriate, some examples are provided from different BoD studies across the world.

RESULTS

In this review article we have identified some of the key methodological choices and challenges that are important to understand when calculating BoD metrics. We have provided examples from different BoD studies that have developed their own strategies in data usage and implementation of statistical methods in the production of BoD estimates.

CONCLUSIONS

With the increase in national BoD studies developing their own strategies in data usage and implementation of statistical methods in the production of BoD estimates, there is a pressing need for equitable capacity building on the one hand, and harmonization of methods on the other hand. In response to these issues, several BoD networks have emerged in the European region that bring together expertise across different domains and professional backgrounds. An intensive exchange in the experience of the researchers in the different countries will enable the understanding of the methods and the interpretation of the results from the local authorities who can effectively integrate the BoD estimates in public health policies, intervention and prevention programs.

A framework for indirect elicitation of the public health impact of gambling problems

Gambling problems are increasingly understood as a health-related condition, with harms from excessive time and money expenditure contributing to significant population morbidity. In many countries, the prevalence of gambling problems is known with some precision. However, the true severity of gambling problems in terms of their impact on health and wellbeing is the subject of ongoing debate. We firstly review recent research that has attempted to estimate harm from gambling, including studies that estimate disability weights using direct elicitation. Limitations of prior approaches are discussed, most notably potential inflation due to non-independent comorbidity with other substance use and mental health conditions, and potential biases in the subjective attribution of morbidity to gambling. An alternative indirect elicitation approach is outlined, and a conceptual framework for its application to gambling is provided. Significant risk factors for propensity to develop gambling problems are enumerated, and relative risks for comorbidities are calculated from recent meta-analyses and reviews. Indirect elicitation provides a promising alternative framework for assessing the causal link between gambling problems and morbidity. This approach requires implementation of propensity score matching to estimate the counterfactual, and demands high quality information of risk factors and comorbid conditions, in order to estimate the unique contribution of gambling problems. Gambling harm is best understood as a decrement to health utility. However, achieving consensus on the severity of gambling problems requires triangulation of results from multiple methodologies. Indirect elicitation with propensity score matching and accounting for comorbidities would provide an important step towards full integration of gambling within a public health paradigm.

Dutch DALYs, current and future burden of disease in the Netherlands

BACKGROUND

The Disability Adjusted Life Year (DALY) is a measure to prioritize in the public health field. In the Netherlands, the DALY estimates are calculated since 1997 and are included in the Public Health Status and Foresight studies which is an input for public health priority setting and policy making. Over these 20 years, methodological advancements have been made, including accounting for multimorbidity and performing projections for DALYs into the future. Most important methodological choices and improvements are described and results are presented.

METHODS

The DALY is composed of the two components years of life lost (YLL) due to premature mortality and years lost due to disability (YLD). Both the YLL and the YLD are distinguished by sex, age and health condition, allowing aggregation to the ICD-10 chapters. The YLD is corrected for multimorbidity, assuming independent occurrence of health conditions and a multiplicative method for the calculation of combined disability weights. Future DALYs are calculated based on projections for causes of death, and prevalence and incidence.

RESULTS

The results for 2015 show that cancer is the ICD-10 chapter with the highest disease burden, followed by cardiovascular diseases and mental disorders. For the individual health conditions, coronary heart disease had the highest disease burden in 2015. In 2040, we see a strong increase in disease burden of dementia and arthrosis. For dementia this is due to a threefold increase in dementia as a cause of death, while for arthrosis this is mainly due to the increase in prevalence.

CONCLUSIONS

To calculate the DALY requires a substantial amount of data, methodological choices, interpretation and presentation of results, and the personnel capacity to carry out all these tasks. However, doing a National Burden of Disease study, and especially doing that for more than 20 years, proved to have an enormous additional value in population health information and thus supports better public health policies.

Adjusting for comorbidity in incidence-based DALY calculations: an individual-based modeling approach

Background

The co-occurrence of two or more medical conditions in the same individual is not uncommon. If disability-adjusted life year (DALY) calculations are carried out for each condition separately, multimorbidity may lead to an overestimation of the morbidity component, the Years Lived with Disability (YLD). Adjusting for comorbidity may be straightforward if all symptoms have same onset and duration; however, when the comorbid health states occur at different time points, an analytical solution to the comorbidity problem becomes more complex. The aim of this study was to develop an individual-based modelling (IBM) approach to adjust incidence-based disease burden estimation for multimorbidity that allows simulating hypothetical individuals and tracking their disease history, including possible comorbidities, over time.

Methods

We demonstrated the IBM approach using an example of external comorbidity, i.e., colon cancer comorbid with healthcare-associated pneumonia (HAP) and by assuming an independent multiplicative model. First, each cumulative progression probabilities were converted to a daily transition probabilities. Second, disability weights for simultaneously experienced health states and duration in each health state were determined. Third, YLD, adjusted for comorbidity, was calculated at every time step. We simulated a cohort of 1000 colorectal cancer patients aged 65 years. Ninety-five percent uncertainty intervals around median YLD values were estimated by Monte Carlo methods.

Results

The median estimated YLD per 1000 cases (due to both cancer and HAP) adjusted for co-morbidity was 545 YLD/1000 (95% interval: 513–585). The impact of not adjusting disability weights for co-existent health states varied from minimal to small; YLD for colorectal cancer would be overestimated only slightly – by 1.6 YLD/1000 – by not adjusting for concurrent HAP. YLD for those HAP patients who have concurrent early-stage colorectal cancer would be overestimated by 2.3 YLD/1000.

Conclusions

The computation of disease burden in the presence of multimorbidity using the incidence-based DALY approach can be handled through IBM. Our approach can be extended to other, more complicated multimorbidity scenarios which are responsible for a high current global disease burden, such as tuberculosis and HIV infection.

The Dutch Public Health Foresight Study 2018: an example of a comprehensive foresight exercise

Background

The use of foresight studies is common in some policy fields, but not in public health. Interest in such studies is growing. This paper gives a general overview of the Dutch Public Health Foresight Study (PHFS) 2018, providing insight into what performing a broad scenario exercise in the field of public health entails and its societal impacts.

Methods

The aim of the PHFS-2018 was: (a) to show how public health and healthcare in the Netherlands will develop over the next 25 years if we pursue our current course and detect ‘new’ developments; (b) to give options for dealing with the major future societal challenges. Part a was addressed by means of a quantitative business-as-usual scenario exercise complemented with qualitative thematic studies, and part b by elaborating courses of action for three key challenges, based on stakeholder consultation. Typical aspects of the PHFS methods are a multidisciplinary, participatory and conceptual approach and using a broad definition of health.

Results

The PHFS-2018 is the basis for the upcoming National Health Policy Memorandum and the Trend Scenario is the baseline for the National Prevention Agreement. Unexpectedly, the findings about increasing mental pressure in young people received most attention. There still is room for expanding use of the study to its full potential.

Conclusions

Long-term thinking could be stimulated by using back casting techniques and stronger involvement of policy-makers in the elaboration of options for action. Lessons learned from developing intersectoral policy at the local level could be applied at the national level.

Disability Weights Measurement for 289 Causes of Disease Considering Disease Severity in Korea

BACKGROUND

For the Korean Burden of Disease (KBD) 2015 study, we have amended disability weights for causes of disease adapting the methodology of the KBD disability weight 2012 study.

METHODS

We conducted a self-administered web-based survey in Korea using ranking five causes of disease. A total of 605 physicians and medical college students who were attending in third or fourth grade of a regular course performed the survey. We converted the ranked data into paired comparison data and ran a probit regression. The predicted probabilities for each cause of disease were calculated from the coefficient estimates of the probit regression. 'Being dead (1)' and 'Full health (0)' were utilized as anchor points to rescale the predicted probability on a scale from 0 to 1.

RESULTS

As a result, disability weights for a total of 289 causes of disease were estimated. In particular, we calculated the disability weights of 60 causes of disease considering severity level. These results show that prejudice about the severity of cause of disease itself can affect the estimation of disability weight, when estimating the disability weight for causes of disease without consideration of severity. Furthermore, we have shown that disability weights can be estimated based on a ranking method which can maximize efficiency of data collection.

CONCLUSION

Disability weights from this study can be used to estimate disability adjusted life year and healthy life expectancy. Furthermore, we expected that the use of the ranking method will increase gradually in disability weight studies.

Multimorbidity Trends in United States Adults, 1988-2014

IMPORTANCE

The simultaneous presence of multiple conditions in one patient (multi-morbidity) is a key challenge facing primary care.

OBJECTIVE

The purpose of this study was to determine the prevalence of multi-morbidity and to document changes in prevalence during the last 25 years.

DESIGN/SETTING

Cross-sectional study using multiple years (1988-2014) of the National Health and Nutrition Examination Survey (NHANES) were analyzed.

SETTING

Multiple years (1988 to 2014) of the National Health and Nutrition Examination Survey (NHANES) from the United States were analyzed.

PARTICIPANTS

Noninstitutionalized adults.

MAIN OUTCOMES AND MEASURES

Number of chronic conditions per individual analyzed by age, race, gender, and socioeconomic factors.

RESULTS

A total of 57,303 individuals were surveyed regarding the presence of multi-morbidity in separate surveys spanning 1988-2014. The overall current prevalence in 2013-2014 of >2 morbidities was 59.6% (95% CI 58.1%-61.1%), 38.5% had 3 or more, and 22.7% had 4 or more morbidities, which was significantly higher than in 1988 (45.7%, 95% CI 43.5%-47.8%, with >2 morbidities). Among individuals with 2 or more morbidities, 54.1% have obesity compared to 41.9% in 1988. Among adults age >65, prevalence was 91.8% for 2 or more morbidities. Whites and Blacks had significantly higher prevalence (59.2% and 60.1%) than Hispanic or "other" race (45.0%, P < .0001). Women (58.4%) had more current multi-morbidities (>2) than men (55.9%, P = .01).

CONCLUSIONS AND RELEVANCE

Multimorbidity is common and has been increasing over the last 25 years. This finding has implications for public health policy and anticipated health costs for the coming years.

The population impact of rheumatic and musculoskeletal diseases in relation to other non-communicable disorders: comparing two estimation approaches

The aim of this study was to quantify the population impact of rheumatic and musculoskeletal diseases (RMDs) with other non-communicable diseases (NCDs), using two complementary strategies: standard multivariate models based on global burden of disease (GBD)-defined groups vs. empirical mutually exclusive patterns of NCDs. We used cross-sectional data from the Portuguese Fourth National Health Survey (n = 23,752). Six GBD-defined groups were included: RMDs, chronic obstructive pulmonary disease or asthma, cancer, depression, diabetes or renal failure, and stroke or myocardial infarction. The empirical approach comprised the patterns "low disease probability", "cardiometabolic conditions", "respiratory conditions" and "RMDs and depression". As recommended by the outcome measures in rheumatology (OMERACT) initiative, health outcomes included life impact, pathophysiological manifestations, and resource use indicators. Population attributable fractions (PAF) were computed for each outcome and bootstrap confidence intervals (95% CI) were estimated. Among GBD-defined groups, RMDs had the highest impact across all the adverse health outcomes, from frequent healthcare utilization (PAF 7.8%, 95% CI 6.2-9.3) to negative self-rated health (PAF 18.1%, 95% CI 15.4-20.6). In the empirical approach, patterns "cardiometabolic conditions" and "RMDs and depression" had similar PAF estimates across all adverse health outcomes, but "RMDs and depression" showed significantly higher impact on chronic pain (PAF 8.9%, 95% CI 7.6-10.3) than the remaining multimorbidity patterns. RMDs revealed the greatest population impact across all adverse health outcomes tested, using both approaches. Empirical patterns are particularly interesting to evaluate the impact of RMDs in the context of their co-occurrence with other NCDs.

Prevalence of metabolic syndrome, discrete or comorbid diabetes and hypertension in sub-Saharan Africa among people living with HIV versus HIV-negative populations: a systematic review and meta-analysis protocol

INTRODUCTION

Metabolic disorder and high blood pressure are common complications globally, and specifically among people living with HIV (PLHIV). Diabetes, metabolic syndrome and hypertension are major risk factors for cardiovascular diseases and their related complications. However, the burden of metabolic syndrome, discrete or comorbid diabetes and hypertension in PLHIV compared with HIV-negative population has not been quantified. This review and meta-analysis aims to compare and analyse the prevalence of these trio conditions between HIV-negative and HIV-positive populations in sub-Saharan Africa (SSA).

METHODS AND ANALYSIS

The Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement guides the methods for this study. Eligibility criteria will be published original articles (English and French language) from SSA that present the prevalence of metabolic syndrome, discrete and/or comorbid diabetes, and hypertension comparisons between PLHIV and HIV-negative populations. The following databases will be searched from January 1990 to February 2017: PubMed/Medline, EBSCOhost, Web of Science, Google Scholar, Scopus, African Index Medicus and Cochrane Database of Systematic Reviews. Eligibility screening and data extraction will be conducted independently by two reviewers, and disagreements resolved by an independent reviewer. Methodological quality and risk of bias will be assessed for individual included studies, while meta-analysis will be used to estimate study outcomes prevalence according to subgroups. Sensitivity analysis will also be performed to further test the robustness of the findings.

ETHICS AND DISSEMINATION

This proposed study does not require ethical approval. The results will be published as a scientific article in a peer-reviewed journal, and presented at conferences and to relevant health agencies.

TRIAL REGISTRATION NUMBER

PROSPERO registration number (CRD42016045727).