After the epidemiologic transition: a reassessment of mortality from infectious diseases among over-65s in France and Italy

Quantifying cause-related mortality in Australia, incorporating multiple causes: observed patterns, trends and practical considerations

BACKGROUND

Mortality statistics using a single underlying cause of death (UC) are key health indicators. Rising multimorbidity and chronic disease mean that deaths increasingly involve multiple conditions. However, additional causes reported on death certificates are rarely integrated into mortality indicators, partly due to complexities in data and methods. This study aimed to assess trends and patterns in cause-related mortality in Australia, integrating multiple causes (MC) of death.

METHODS

Deaths (n = 1 773 399) in Australia (2006-17) were mapped to 136 ICD-10-based groups and MC indicators applied. Age-standardized cause-related rates (deaths/100 000) based on the UC (ASRUC) were compared with rates based on any mention of the cause (ASRAM) using rate ratios (RR = ASRAM/ASRUC) and to rates based on weighting multiple contributing causes (ASRW).

RESULTS

Deaths involved on average 3.4 causes in 2017; the percentage with >4 causes increased from 20.9 (2006) to 24.4 (2017). Ischaemic heart disease (ASRUC = 73.3, ASRAM = 135.8, ASRW = 63.5), dementia (ASRUC = 51.1, ASRAM = 98.1, ASRW = 52.1) and cerebrovascular diseases (ASRUC = 39.9, ASRAM = 76.7, ASRW = 33.5) ranked as leading causes by all methods. Causes with high RR included hypertension (ASRUC = 2.2, RR = 35.5), atrial fibrillation (ASRUC = 8.0, RR = 6.5) and diabetes (ASRUC = 18.5, RR = 3.5); the corresponding ASRW were 12.5, 12.6 and 24.0, respectively. Renal failure, atrial fibrillation and hypertension ranked among the 10 leading causes by ASRAM and ASRW but not by ASRUC. Practical considerations in working with MC data are discussed.

CONCLUSIONS

Despite the similarities in leading causes under the three methods, with integration of MC several preventable diseases emerged as leading causes. MC analyses offer a richer additional perspective for population health monitoring and policy development.

Diversification in causes of death in low-mortality countries: emerging patterns and implications

INTRODUCTION

An important role of public health organisations is to monitor indicators of variation, so as to disclose underlying inequality in health improvement. In industrialised societies, more individuals than ever are reaching older ages and have become more homogeneous in their age at death. This has led to a decrease in lifespan variation, with substantial implications for the reduction of health inequalities. We focus on a new form of variation to shed further light on our understanding of population health and ageing: variation in causes of death.

METHODS

Data from the WHO Mortality Database and the Human Mortality Database are used to estimate cause-of-death distributions and life tables in 15 low-mortality countries. Cause-of-death variation, using 19 groups of causes, is quantified using entropy measures and analysed from 1994 to 2017.

RESULTS

The last two decades have seen increasing diversity in causes of death in low-mortality countries. There have been important reductions in the share of deaths from diseases of the circulatory system, while the share of a range of other causes, such as diseases of the genitourinary system, mental and behavioural disorders, and diseases of the nervous system, has been increasing, leading to a more complex cause-of-death distribution.

CONCLUSIONS

The diversification in causes of death witnessed in recent decades is most likely a result of the increase in life expectancy, together with better diagnoses and awareness of certain diseases. Such emerging patterns bring additional challenges to healthcare systems, such as the need to research, monitor and treat a wider range of diseases. It also raises new questions concerning the distribution of health resources.

Zero or More: Methodological Challenges of Counting and Estimating Deaths Related to Antibiotic-resistant Infections

Estimates of the number of deaths from antimicrobial-resistant (AMR) infections are important data for clinicians and public health officials advocating for resources to prevent and treat these infections. The aims of this article are to describe the various approaches to calculating deaths from AMR infections, to compare the tally of deaths by each approach, and to explain how to interpret the results. Currently, none of the 3 methods employed by vital statistics systems to count deaths from specific causes (underlying cause of deaths, multiple causes of death, and avoidable deaths) count deaths from AMR infections. These deaths can be estimated by 4 approaches: case-fatality rate, infection-related mortality, and excess mortality using controls with antibiotic-susceptible infections or controls without antibiotic-resistant infections. When encountering discrepant estimates of AMR-related deaths, it is important to consider which method was used and whether it was the right method to answer the question being asked.

The increase of sepsis-related mortality in Italy: a nationwide study, 2003-2015

The true burden of sepsis is largely unknown. Conventional underlying cause of death (UCoD) statistics largely underestimates sepsis-related mortality. This study aims to analyze all the conditions mentioned in the death certificates (multiple causes of death-MCoD) to estimate the nationwide burden of sepsis-related mortality in Italy, to investigate time trends and main comorbidities in sepsis-related deaths. All death certificates mentioning sepsis from 2003 to 2015 were analyzed. Age-standardized mortality rates were calculated for sepsis as both UCoD and MCoD, by gender and broad age groups. The ratio of the age-standardized proportions of any mention of sepsis in the presence/absence of associated chronic diseases (ASPR) was computed. The number of certificates reporting sepsis increased from 18,939 in 2003 to 49,010 in 2015 (from 3 to 8% of all deaths). The increase in sepsis mortality rates was larger for UCoD (males, + 200%; females, + 175%) than for MCoD-based figures (+ 100%; + 90%); MCoD rates remained noticeably higher than UCoD rates (2015, 87.3 per 100,000 vs. 16.3 for males; 54.9 vs. 11.8 for females). The largest increase was observed among the very elderly. The association between sepsis and chronic diseases was stronger for subjects aged less than 75 years. The increased awareness within the medical community in addition to the growing susceptible elderly population and the spread of antimicrobial resistance could have contributed to the sepsis-related mortality increase. MCoD statistics could help in recognizing sepsis not only as a clinical challenge, but also as a major public health issue.

CD4:8 Ratio Above 5 Is Associated With All-Cause Mortality in CMV-Seronegative Very Old Women: Results From the BELFRAIL Study

The occurrence and general applicability of the CD4:8 ratio as a surrogate predictor of mortality among the oldest old have only been tested in a few longitudinal studies. Here, the predictive value of CD4:8 ratio for mortality with respect to the role of cytomegalovirus (CMV) infection was investigated. Using polychromatic flow cytometry, the CD4:8 ratio and T-cell subsets of 235 individuals aged 81.5 years or older were analyzed, and mortality data were collected after a mean period of 3.3 years. The hazard for all-cause mortality adjusted for age, comorbidity, and CMV serostatus increased 1.53-fold (95% CI: 0.94-2.51) with every increment in the CD4:8 ratio from R < 1, to 1 < R < 5 and R > 5 among women. A negative hazard ratio of 0.50 for CMV seropositivity in women indicated an apparently protective effect of this virus. In men, no associations with survival were observed. No mediation effect could be found for the CD4:8 ratio with respect to the relationship between CMV serostatus and mortality. Very elderly CMV-negative women with a R > 5 experienced the highest mortality rates, independent of age and comorbidity. The associations of CMV serostatus and CD4:8 ratio with mortality seem to reflect distinct pathways mediating life span in very old humans.

Obesity-related mortality in France, Italy, and the United States: a comparison using multiple cause-of-death analysis

OBJECTIVES

We investigate the reporting of obesity on death certificates in three countries (France, Italy, and the United States) with different levels of prevalence, and we examine which causes are frequently associated with obesity.

METHODS

We use cause-of-death data for all deaths at ages 50-89 in 2010-2011. Since obesity may not be the underlying cause (UC) of death, we compute age- and sex-standardized death rates considering all mentions of obesity (multiple causes or MC). We use cluster analyses to identify patterns of cause-of-death combinations.

RESULTS

Obesity is selected as UC in no more than 20% of the deaths with a mention of obesity. Mortality levels, whether measured from the UC or the MC, are weakly related to levels of prevalence. Patterns of cause-of-death combinations are similar across the countries. In addition to strong links with cardiovascular diseases and diabetes, we identify several less familiar associations.

CONCLUSIONS

Considering all mentions on the deaths certificates reduces the underestimation of obesity-related mortality based on the UC only. It also enables us to describe the various mortality patterns involving obesity.

Growing burden of sepsis-related mortality in northeastern Italy: a multiple causes of death analysis

BACKGROUND

Few population-based data are available on mortality due to sepsis. The aim of the study was to estimate sepsis-related mortality rates and to assess the associated comorbidities.

METHODS

From multiple causes of death data (MCOD) of the Veneto Region (northeastern Italy), all deaths with sepsis mentioned anywhere in the death certificate were retrieved for the period 2008-2013. Among these deaths the prevalence of common chronic comorbidities was investigated, as well as the distribution of the underlying cause of death (UCOD), the single disease selected from all condition mentioned in the certificate and usually tabulated in mortality statistics. Age-standardized mortality rates were computed for sepsis selected as the UCOD, and for sepsis mentioned anywhere in the certificate.

RESULTS

Overall 16,906 sepsis-related deaths were tracked. Sepsis was mentioned in 6.3 % of all regional deaths, increasing from 4.9 in 2008 to 7.7 % in 2013. Sepsis was the UCOD in 0.6 % of total deaths in 2008, and in 1.6 % in 2013. Age-standardized mortality rates increased by 45 % for all sepsis-related deaths, and by 140 % for sepsis as the UCOD. Sepsis was often reported in the presence of chronic comorbidities, especially neoplasms, diabetes, circulatory diseases, and dementia. Respiratory tract and intra-abdominal infections were the most frequently associated sites of infection.

CONCLUSIONS

MCOD analyses provide an estimate of the burden of sepsis-related mortality. MCOD data suggest an increasing importance attributed to sepsis by certifying physicians, but also a real increase in mortality rates, thus confirming trends reported in some other countries by analyses of hospital discharge records.