Trends in frequency of reporting improper diabetes-related cause-of-death statements on death certificates, 1985-2005: An algorithm to identify incorrect causal sequences

Age at Type 2 Diabetes Diagnosis and Cause-Specific Mortality: Observational Study of Primary Care Patients in England

OBJECTIVE

To examine the associations between age at type 2 diabetes diagnosis and the relative and absolute risk of all-cause and cause-specific mortality in England.

RESEARCH DESIGN AND METHODS

In this cohort study using primary care data from the Clinical Practice Research Datalink, we identified 108,061 individuals with newly diagnosed type 2 diabetes (16-50 years of age), matched to 829,946 individuals without type 2 diabetes. We estimated all-cause and cause-specific mortality (cancer, cardiorenal, other [noncancer or cardiorenal]) by age at diagnosis, using competing-risk survival analyses adjusted for key confounders.

RESULTS

Comparing individuals with versus without type 2 diabetes, the relative risk of death decreased with an older age at diagnosis: the hazard ratio for all-cause mortality was 4.32 (95% CI 3.35-5.58) in individuals diagnosed at ages 16-27 years compared with 1.53 (95% CI 1.46-1.60) at ages 48-50 years. Smaller relative risks by increasing age at diagnosis were also observed for cancer, cardiorenal, and noncancer or cardiorenal death. Irrespective of age at diagnosis, the 10-year absolute risk of all-cause and cause-specific mortality were higher in individuals with type 2 diabetes; yet, the absolute differences were small.

CONCLUSIONS

Although the relative risk of death in individuals with versus without type 2 was higher at younger ages, the 10-year absolute risk of all investigated causes of death was small and similar in the two groups. Further multidecade studies could help estimate the long-term risk of complications and death in individuals with early-onset type 2 diabetes.

Splanchnic vein thrombosis-related mortality in the Veneto region (Italy), 2008-2019: Retrospective analysis of epidemiological data

BACKGROUND

Splanchnic vein thrombosis (SVT) is an uncommon manifestation of venous thromboembolism. Epidemiological data on SVT-related mortality rate is not available to date.

METHODS

We investigated time trends in SVT-related mortality rate, 2008-2019, in Veneto, an Italian high-income region of approximatively 5,000,000 inhabitants. SVT-related deaths were identified by the following ICD-10 codes: I81 (portal vein thrombosis), K75.1 (phlebitis of portal vein), K76.3 (liver infarction), K76.5 (hepatic veno-occlusive disease) or I82.0 (Budd-Chiari syndrome).

RESULTS

During the study period, a total of 557,932 deaths were recorded. SVT was reported in 823 cases; 776 (94%) consisted of portal vein thrombosis. The age-standardized SVT-related mortality rate varied from 1.47 (year 2008) to 1.52 (year 2019) per 100,000 person-years. An increase in the cause-specific annual mortality rate was observed in women (0.56 in 2008 to 1.04 per 100,000 person-years in 2019; average annual percent change +5.7%, 95%CI +3.1; +8.3%). In men, the cause-specific mortality rate moved from 2.53 in 2008 to 2.03 per 100,000 person-years in 2019 (average annual percent change -1.2%, 95%CI -4.0; +1.6%). After conditioning for age and sex, the odds of having a concomitant liver disease were higher for SVT-related deaths (OR 31.6; 95%CI 17.1-37.0) compared with non-SVT-related deaths. This also applies to gastrointestinal cancers (OR 1.28; 95%CI 1.07-1.55), although to a lesser extent.

CONCLUSIONS

We report first epidemiological estimates of SVT-related mortality in a Western country. These values will serve as a reference to weight novel potential factors associated with SVT-related death and interpret them from an epidemiological perspective.

Increasing epilepsy-related mortality: A multiple causes of death study in Northern Italy

PURPOSE

to assess the burden of epilepsy as the underlying or contributory cause of death, to investigate time trends in mortality with epilepsy, and to examine the main associated comorbidities.

METHODS

All deaths from January 1, 2008 to December 31, 2019 with any mention of epilepsy were retrieved from the mortality register of the Veneto Region (Italy). The average annual percent change (AAPC) in age-standardized mortality rates was estimated by log-linear models. The association between mention of epilepsy and of selected disease categories in death certificates was assessed by conditional logistic regression.

RESULTS

Any mention of epilepsy was reported in 5,907 death certificates; of these, epilepsy was selected as the underlying cause in 1,020 decedents. Deaths with epilepsy represented 0.8% of total mortality in 2008-2011, increasing to 1.3% in 2016-2019. The AAPC was 4.7% for males (95% CI 3.0-6.4, p<0.001) and 6.2% for females (95% CI 4.5-7.9, p<0.001). A strong association was found between mention of epilepsy and meningitis/encephalitis, congenital anomalies/cerebral palsy and other paralytic syndromes, central nervous system tumours, cerebrovascular diseases, and dementia/Alzheimer.

CONCLUSIONS

The present analysis from Southern Europe confirms recent reports limited to the UK and the US on increasing epilepsy-related mortality rates. aging of the population and the growing prevalence of neurological disorders are among long-term causes of this unfavorable trend; further studies on mortality data and other health archives are warranted.

Decline in Overall Pulmonary Embolism-Related Mortality and Increasing Prevalence of Cancer-Associated Events in the Veneto Region (Italy), 2008-2019

BACKGROUND

 Despite evidence of ongoing epidemiological changes in deaths from venous thromboembolism in high-income countries, little recent information is available on the time trends in mortality related to pulmonary embolism (PE) as underlying or concomitant cause of death in Europe.

METHODS

 We accessed the regional database of death certificates of Veneto Region (Northern Italy, population 4,900,000) from 2008 to 2019. We analyzed the trends in crude and age-adjusted annual rates of mortality related to PE (reported either as underlying cause or in any position in the death certificate) using Joinpoint regression; in the contribution of PE to mortality (proportionate mortality); and, using logistic regression, in the association between PE and cancer at death.

RESULTS

 Between 2008 and 2019, the annual age-standardized mortality rate related to PE in Veneto decreased from 20.7 to 12.6 deaths per 100,000 population for PE in any position of the death certificate, and from 4.6 to 2.2 deaths per 100,000 population for PE as underlying cause of death. PE-related proportionate mortality remained up to twice as high in women. The age- and sex-adjusted odds ratio for cancer in deaths with versus without PE constantly increased from 1.01 (95% confidence interval [CI]: 0.88-1.16) in 2008 to 1.58 (95% CI: 1.35-1.83) in 2019.

CONCLUSION

 The descending trends in PE-related mortality reported for Europe up to 2015 for both sexes continued thereafter in this high-income region of Northern Italy. However, sex differences in proportionate mortality persist. The increasing strength in the association between cancer and PE may indicate a change in risk factor distribution, calling for tailored management practices in this patient group.

Disability trajectories prior to death for ten leading causes of death among middle-aged and older adults in Taiwan

BACKGROUND

Prolonged life expectancy is associated with increased prevalence of chronic diseases. The aim of this study was to determine the different disability trajectories for the top ten leading causes of death in Taiwan .

METHODS

A total of 2,431 participants aged 50-96 in 1996 from the Taiwan longitudinal study on aging (TLSA) who died from 1996 to 2016 were analyzed. Integration of Cause of Death Data and TLSA helped sort out participants who had died from the ten leading causes of death. The level of physical disability was evaluated with the Activities of Daily Living Scale (ADLs), ranging from 0 to 6 points, in 1996, 1999, 2003, 2007, and 2011. A multilevel model was used to investigate the levels and rates of change in disability development before death.

RESULTS

The outcome of the research showed that the earliest group to experience physical limitation was individuals living with diabetes. The groups with the highest ADL scores were participants with diabetes, cerebrovascular disease, and hypertension-related diseases. Most groups reach ADL scores ≥ 1 (mild-level) during 4-6 years before death except chronic hepatitis and cirrhosis and injury.

CONCLUSIONS

People who had died from the ten leading causes of death experienced different disability trajectories before death. The trajectory of the participants who had died from diabetes showed a unique pattern with the earliest occurrence and more severe deterioration in terms of development of disabilities. Disability trajectories provide a prediction of survival status for middle-aged and older adults associated with the ten leading causes of death.

Mortality Associated with Idiopathic Pulmonary Fibrosis in Northeastern Italy, 2008-2020: A Multiple Cause of Death Analysis

Mortality from idiopathic pulmonary fibrosis (IPF) is increasing in most European countries, but there are no data for Italy. We analysed the registry data from a region in northeastern Italy to assess the trends in IPF-related mortality during 2008–2019, to compare results of underlying vs. multiple cause of death analyses, and to describe the impact of the COVID-19 epidemic in 2020. We identified IPF (ICD-10 code J84.1) among the causes of death registered in 557,932 certificates in the Veneto region. We assessed time trends in annual age-standardized mortality rates by gender and age (40–74, 75–84, and ≥85 years). IPF was the underlying cause of 1310 deaths in the 2251 certificates mentioning IPF. For all age groups combined, the age-standardized mortality rate from IPF identified as the underlying cause of death was close to the European median (males and females: 3.1 and 1.3 per 100,000/year, respectively). During 2008–2019, mortality rates increased in men aged ≥85 years (annual percent change of 6.5%, 95% CI: 2.0, 11.2%), but not among women or for the younger age groups. A 72% excess of IPF-related deaths was registered in March–April 2020 (mortality ratio 1.72, 95% CI: 1.29, 2.24). IPF mortality was increasing among older men in northeastern Italy. The burden of IPF was heavier than assessed by routine statistics, since less than two out of three IPF-related deaths were directly attributed to this condition. COVID-19 was accompanied by a remarkable increase in IPF-related mortality.

Causes of mortality in a large population-based cohort of psychiatric patients in Southern Europe

The World Health Organization considers excess morbidity and mortality among people with mental disorders as a high public health priority. This study aims to estimate the mortality risk and causes of death among a large population-based cohort of psychiatric patients. All residents in Veneto (Northeastern Italy) aged between 18 and 84 years with a contact with Community Mental Health Centers in 2008 and a psychiatric diagnosis (n = 54,350) were followed-up for 10 years. Standardized Mortality Ratios (SMR) and excess mortality were computed, with the general regional population as a reference. Mortality was more than doubled (males SMR = 2.4; females SMR = 2.2) and the relative increase in mortality was much larger in young and middle-aged adults (18-44 and 45-64 years) across all diagnostic groups. The most frequent causes were circulatory diseases (27%) and neoplasms (26%). Although the risk was increased by about tenfold, deaths from suicide were limited to 6% and 4% of all decedents in males and females, respectively. Patients with schizophrenia showed a very high risk for mortality for diabetes and cardiovascular disorders. A large excess was found also for respiratory diseases and a two-fold increase for lung cancer in males and breast cancer in females. Although chronic physical disorders are known to be the main causes of mortality in such patients, they receive far less attention than suicide or accidents. Our results suggest that there is still a need to plan actions to prevent excess mortality and to improve the quality of life of patients with mental disorders.

Diabetic mortality risk among cancer patients in the United State SEER population, 1975-2016

BACKGROUND

The focus on diabetic mortality in cancer patients remains superficial. The objective of our study is to identify cancer patients with the highest risk of diabetic mortality compared with other cancer patients and the general US population.

METHODS

The representative data of cancer patients dying from diabetes between 1975 and 2016 was retrieved from the Surveillance, Epidemiology, and End Results program. Standardized mortality ratios (SMRs) and excess risks for multiple cancer sites were calculated. Cox regression analysis was performed to identify potential risk factors of death from diabetes.

RESULTS

Among 9,043,788 cancer patients diagnosed between 1975 and 2016, 51,611 patients died from diabetes. the SMR of diabetic death was 2.15 compared with the general population. Malignancies of pancreas, liver, and brain had the highest SMR (>15) compared with the general population. The risk of death from diabetes was increasing in more recent years. The majority of deaths from diabetes occurred in those >45 years of age diagnosed with prostate, breast, colorectum, lung, or bladder cancer. Patients with older age, male sex, black race, higher histologic grade, unmarried status, and not undergoing surgery are at higher risk compared with other cancer survivors.

CONCLUSIONS

Compared to the general population, cancer patients are at elevated risk of death from diabetes throughout the follow-up period. Elderly, black, unmarried males with distant metastases and without receiving surgery are recommended with earlier detection and more efficient diabetic care, especially for those with prostate, breast, colorectum, lung, or bladder cancer.

Overall mortality and causes of death in newly admitted nursing home residents

BACKGROUND

In spite of a rapidly ageing population, there is a lack of population-based data on mortality among nursing home residents in Southern Europe.

AIMS

To assess mortality rates, their determinants, and causes of death in newly admitted nursing home residents in the Veneto region (northeastern Italy).

METHODS

19,392 subjects aged ≥ 65 years admitted to regional nursing homes during 2015-2017 were recruited in a cohort mortality study based on linked health records. Risk factors for mortality were investigated by Cox regression. The distribution of causes of death was retrieved from death certificates.

RESULTS

Mortality peaked in the first 4 months after admission; thereafter the monthly mortality rate fluctuated around 3% in males and 2% in females. Overall mortality was 23% at 6 months and 34% at 1 year. In addition to age, gender, and dependency, main risk factors for mortality were recent hospitalization (first 4 months after entry into the facility), and the burden of comorbidities (subsequent follow-up period). The most represented causes of mortality were similar in the first and in the subsequent period after admission: cardio-cerebrovascular diseases, neurodegenerative diseases, respiratory diseases, and infections.

DISCUSSION

The first months after admission represent a period at high risk of mortality, especially for patients with a recent hospitalization. Causes reported in death certificates suggest mainly an acute deterioration of pre-existing chronic conditions.

CONCLUSION

Health care plans should be personalized for newly admitted vulnerable patients. Palliative care needs should be recognized and addressed for high-risk non-cancer patients.

Leading causes of death among decedents with mention of schizophrenia on the death certificates in the United States

BACKGROUND

Little is known about the changes in the ranking of leading cause of death (COD) among people died with schizophrenia across years in the United States (U.S.). This study aims to determine the ranking of leading COD among U.S. decedents with mention of schizophrenia by age from 2000 to 2015.

METHODS

The mortality multiple COD files maintained by the National Center for Health Statistics were used to identify decedents aged 15 years old and above with mention of schizophrenia anywhere on the death certificates to determine the number and proportion of deaths attributed to various underlying CODs.

RESULTS

Of 13,289, 13,655, 14,135, and 15,033 people who died in 2000-2003, 2004-2007, 2008-2011and 2012-2015 with mention of schizophrenia, similar to all decedents, heart disease and cancer was the first and the second leading COD throughout the study years. Schizophrenia ranked the third in most years except in 2004-2007. The first leading COD for decedents with mention of schizophrenia aged 15-24, 25-44, 45-64, 65-74, and 75+ years old in 2012-2015 was suicide, accidents, heart disease, heart disease, and Alzheimer's disease and related dementia, respectively. Nevertheless, it was accidents, accidents, cancer, cancer, and heart disease, respectively for all decedents.

CONCLUSION

The ranking of leading CODs among U.S. decedents with mention of schizophrenia changed across years and differed from all decedents by age, which suggest that different interventions should be designed accordingly.

Global burden of hypoglycaemia-related mortality in 109 countries, from 2000 to 2014: an analysis of death certificates

AIMS/HYPOTHESIS

In the context of increasing prevalence of diabetes in elderly people with multimorbidity, intensive glucose control may increase the risk of severe hypoglycaemia, potentially leading to death. While rising trends of severe hypoglycaemia rates have been reported in some European, North American and Asian countries, the global burden of hypoglycaemia-related mortality is unknown. We aimed to investigate global differences and trends of hypoglycaemia-related mortality.

METHODS

We used the WHO mortality database to extract information on death certificates reporting hypoglycaemia or diabetes as the underlying cause of death, and the United Nations demographic database to obtain data on mid-year population estimates from 2000 to 2014. We calculated crude and age-standardised proportions (defined as number of hypoglycaemia-related deaths divided by total number of deaths from diabetes [i.e. the sum of hypoglycaemia- and diabetes-related deaths]) and rates (hypoglycaemia-related deaths divided by mid-year population) of hypoglycaemia-related mortality and compared estimates across countries and over time.

RESULTS

Data for proportions were extracted from 109 countries (31 had data from all years analysed [2000-2014] available). Combining all countries, the age-standardised proportion of hypoglycaemia-related deaths was 4.49 (95% CI 4.44, 4.55) per 1000 total diabetes deaths. Compared with the overall mean, most Central American, South American and (mainly) Caribbean countries reported higher proportions (five more age-standardised hypoglycaemia-related deaths per 1000 total diabetes deaths in Chile, six in Uruguay, 11 in Belize and 22 in Aruba), as well as Japan (11 more age-standardised hypoglycaemia-related deaths per 1000 total diabetes deaths). In comparison, lower proportions were noted in most European countries, the USA, Canada, New Zealand and Australia. For countries with data available for all years analysed, trend analysis showed a 60% increase in hypoglycaemia-related deaths until 2010 and stable trends onwards. Rising trends were most evident for Argentina, Brazil, Chile, the USA and Japan. Data for rates were available for 105 countries (30 had data for all years analysed [2000-2014] available). Combining all countries, the age-standardised hypoglycaemia-related death rate was 0.79 (95% CI 0.77, 0.80) per 1 million person-years. Most Central American, South American and Caribbean countries similarly reported higher rates of hypoglycaemia-related death, whilst virtually all European countries, the USA, Canada, Japan, New Zealand and Australia reported lower rates compared with the overall mean. Age-standardised rates were very low for most countries (lower than five per 1 million person-years in 89.5% of countries), resulting in small absolute differences among countries. As noted with the proportions analysis, trend analysis showed an overall 60% increase in hypoglycaemia-related deaths until 2010 and stable rate trends onwards; rising rates were particularly evident for Brazil, Chile and the USA.

CONCLUSIONS/INTERPRETATION

Most countries in South America, Central America and the Caribbean showed the highest proportions of diabetes-related deaths attributable to hypoglycaemia and the highest rates of hypoglycaemia-related deaths. Between 2000 and 2014, rising trends were observed in Brazil, Chile and the USA for both rates and proportions of hypoglycaemia-related death, and in Argentina and Japan for proportions only. Further studies are required to unravel the contribution of clinical and socioeconomic factors, difference in diabetes prevalence and heterogeneity of death certification in determining lower rates and proportions of hypoglycaemia-related deaths in high-income countries in Europe, North America and Asia.

DATA AVAILABILITY

Data used for these analyses are available at https://doi.org/10.17632/ndp52fbz8r.1.

Mortality from infectious diseases in diabetes

BACKGROUND AND AIMS

To investigate the risk of mortality from infections by comparing the underlying causes of death versus the multiple causes of death in known diabetic subjects living in the Veneto region of Northern Italy.

METHODS AND RESULTS

A total of 185,341 subjects with diabetes aged 30-89 years were identified in the year 2010, and causes of death were assessed from 2010 to 2015. Standardized Mortality Ratios (SMRs) with 95% confidence intervals (CIs) were computed with regional mortality rates as reference. The underlying causes of death and all the diseases reported in the death certificates were scrutinized. At the end of the follow-up, 36,382 subjects had deceased. We observed an increased risk of death from infection-related causes in subjects with diabetes with a SMR of 1.83 (95% CI, 1.71-1.94). The SMR for death from septicemia was 1.91 (95% CI, 1.76-2.06) and from pneumonia was 1.47 (95% CI, 1.36-1.59). The use of the multiple causes of death approach emphasized the association of infectious diseases with mortality.

CONCLUSION

The results of the present study demonstrate an excess mortality due to infection-related diseases in patients with diabetes; more interestingly, by routine mortality analyses, the results show a possible underestimation of the effect of these diseases on mortality.

Mortality and quality of death certification in a cohort of patients with Parkinson's disease and matched controls in North Wales, UK at 18 years: a community-based cohort study

OBJECTIVE

This investigation reports the cause and the quality of death certification in a community cohort of patients with Parkinson's disease (PD) and controls at 18 years.

SETTING

Denbighshire North Wales, UK.

PARTICIPANTS

The community-based cohorts consisted of 166 patients with PD and 102 matched controls.

PRIMARY OUTCOMES

All-cause mortality was ascertained at 18 years by review of hospitals' primary care records and examination of death certificates obtained from the UK General Register Office. Mortality HRs were estimated using Cox proportional regression, controlling for covariates including age at study entry, age at death, gender, motor function, mood, health-related quality of life (HRQoL) and cognitive function.

RESULTS

After 18 years, 158 (95%) of patients in the PD cohort and 34 (33%) in the control cohort had died. Compared with the general UK population, the PD cohort had a higher risk of mortality (standard mortality rate, 1.82, 95% CI 1.55 to 2.13). As the primary or underlying cause of death, PD was not reported in 75/158 (47%) of the death certificates. In addition, although 144/158 (91%) of the PD cohort had a diagnosis of dementia, this was reported in less than 10% of death certificates. The main cause of death reported in the PD cohort was pneumonia (53%), followed by cardiac-related deaths (21%). Compared with controls, patients with PD had a greater risk of pneumonia (2.03, 95% CI 1.34 to 3.6), poorer HRQoL and more likely to reside in institutional care at death (P<0.01).

CONCLUSION

This investigation found that PD was associated with an excess risk of mortality compared with the general population. However, PD as a primary or underlying cause of death recorded on certificates was found to be suboptimal. This suggests that the quality of mortality statistics drawn from death certificates alone is not a valid or reliable source of data.

Examination of Cause-of-Death Data Quality Among New York City Deaths Due to Cancer, Pneumonia, or Diabetes From 2010 to 2014

The cause-of-death (COD) statement on the standard US death certificate is a valuable tool for public health practice, but its utility is impaired by reporting inaccuracies. To assess the quality of CODs reported in New York City, we developed and applied a quality measure to 3 leading CODs: cancer, pneumonia, and diabetes. The COD quality measure characterized 5 common issues with COD completion: nonspecific conditions as the underlying COD (UCOD); UCOD discrepancies; the presence of only 1 informative cause on the entire certificate; competing causes listed together on 1 line; and clinically improbable sequences. COD statements with more than 1 quality issue were defined as statements of "limited" quality. Of 82,116 deaths with cancer, diabetes, or pneumonia assigned as the UCOD in New York City from 2010 to 2014, 66.8% of pneumonia certificates were classified as "limited" quality as compared with 45.6% of cancer certificates and 32.3% of diabetes certificates. Forty percent of cancer certificates listed only 1 informative condition on the death certificate. Almost half of pneumonia certificates (45.9%) contained only enough information to assign International Classification of Diseases, Tenth Revision, code J18.9 ("unspecified pneumonia") as the UCOD, whereas most diabetes certificates contained UCOD discrepancies (25.2%). These limitations affect the quality of mortality data but may be reduced through quality improvement efforts.

Excess mortality in 2015: a time series and cause-of-death analysis in Northern Italy

AIMS

To investigate the excess mortality registered in the Veneto Region (Northern Italy) in 2015.

METHODS

A Seasonal Autoregressive Integrated Moving Average Model was applied to predict overall mortality expected in 2014-2015 based on that observed in 2000-2013. The annual percent change in age-standardized rates (APC) was estimated for specific causes of death in 2007-2015.

RESULTS

Compared to 2014, the number of deaths and the overall age-standardized mortality increased in 2015 by 7.8 and 4.5%, respectively. When accounting for time trends, the observed mortality was lower than expected in 2014 (-4.5%) and slightly higher in 2015 (+1.1%). In 2015, mortality increased especially for causes with an already rising trend: neurologic/psychiatric (APC = 1.2; 95% Confidence Interval 0.3-2.0%) and infectious diseases (APC = 5.9; 3.6-8.2%).

CONCLUSIONS

Short-term changes and long-term trends in mortality must be interpreted within the frame of a rapid growth in the population of elderly subjects affected by multiple comorbidities.

Increase in Parkinson's disease-related mortality among males in Northern Italy

BACKGROUND

According to standard mortality statistics based on the underlying cause of death (UCOD), mortality from Parkinson's disease (PD) is increasing in most European countries. However, mortality trends are better investigated taking into account all the diseases reported in the death certificate (multiple causes of death approach, MCOD).

METHODS

All deaths of residents in the Veneto Region (Northern Italy) aged≥45 years with any mention of PD were extracted from 2008 to 2015. The Annual Percent Change (APC) in age-standardized mortality rates was computed both for PD as the UCOD, and by MCOD. The association with common chronic comorbidities and acute complications was investigated by log-binomial regression. The frequency of the mention of PD in death certificates was investigated through linkage with an archive of patients with a previous clinical diagnosis of the disease.

RESULTS

PD was reported in 2.1% of all deaths, rising from 1.9% in 2008 to 2.4% in 2015. Among males, age-standardized rates increased over time both in analyses based on the UCOD (APC +4.1%; Confidence Interval +1.5%,+6.7%), and on MCOD (APC +2.2%; +0.2,+4.2%). Among females time trends were not significant. Mention of PD was associated with that of dementia/Alzheimer and acute infectious diseases. Among known PD patients, the disease was reported only in 60.2% of death certificates.

CONCLUSIONS

Mortality associated to PD is steeply increasing among males in Northern Italy; further investigations on time trends for PD, both through all available electronic health archives and clinical studies, should be set as a priority for epidemiological research.

Lung and kidney: a dangerous liaison? A population-based cohort study in COPD patients in Italy

Background

COPD is among the major causes of death, and it is associated with several comorbid conditions. Chronic kidney disease (CKD) is frequently diagnosed in older people living in Western societies and could impact COPD patients’ mortality. We evaluated the relationship between burden of comorbidities, CKD, and mortality in a population-based cohort of patients discharged with a diagnosis of COPD.

Methods

A longitudinal cohort study was conducted evaluating 27,272 COPD patients. Recruitment of COPD subjects and identification of CKD and other comorbidities summarized by the Charlson comorbidity index (CCI) were based on claims data coded according to the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM). Severity of COPD was classified by hospital diagnosis or exemption from medical charges due to respiratory failure or previous hospitalizations for COPD. The impact of comorbidities on survival was assessed by Cox regression.

Results

Less than 40% of patients were still alive at the end of a median follow-up of 37 months (17 months for patients who died and 56 months for those alive at the end of follow-up). After adjustment for age, gender, and severity score of COPD, CKD (hazard ratio =1.36, 95% confidence interval 1.30–1.42) independently from comorbidities summarized by the CCI was a significant risk factor for mortality.

Conclusion

In spite of limitations due to the use of claims data, long-term survival of COPD patients was heavily affected by the presence of CKD and other comorbidities.

Contemporary Burden of Atrial Fibrillation and Associated Mortality in Northeastern Italy

Based on different estimation methods, mortality attributable to atrial fibrillation (AF) has been demonstrated to increase over time in developed countries, reaching a share ranging from 1% to 5% of overall deaths. To assess the whole burden of AF-associated mortality, all diseases mentioned in death certificates of subjects aged ≥45 years resident in the Veneto Region (Northeastern Italy) were analyzed for the 2008 to 2013 period. The prevalence of common chronic co-morbidities was compared between deaths with mention of AF and a sample of age-matched deaths without reported AF. The disease was mentioned among conditions contributing to death in 25,834 subjects, corresponding to 9.8% of all regional deaths. Rates of AF-associated mortality were higher in men and increased steeply with age, being above 1 per 100 among residents aged ≥85 years. Compared with non-AF-associated deaths, the strongest associations were observed between AF and hypertensive diseases (prevalence ratio 1.62, 95% CI 1.57 to 1.67), cardiac valve disorders (2.43, 2.25 to 2.61), cardiomyopathies (1.93, 1.70 to 2.19), cerebrovascular diseases (1.55, 1.50 to 1.60), and chronic obstructive pulmonary disease (1.49, 1.42 to 1.57). AF-associated mortality resulted higher than previously reported, probably due to aging of the population with multiple predisposing diseases, an increased recognition of AF among the elderly, and a raised awareness of certifying physicians about the importance of AF. Analyses of all diseases mentioned in death certificates underscored the interaction of AF with several other circulatory and respiratory disorders in pathologic networks leading to an increased risk of death.

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.

Accuracy of Death Certificates and Assessment of Factors for Misclassification of Underlying Cause of Death

Background

Cause of death (COD) information taken from death certificates is often inaccurate and incomplete. However, the accuracy of Underlying CODs (UCODs) recorded on death certificates has not been comprehensively described when multiple diseases are present.

Methods

A total of 450 consecutive autopsies performed at a geriatric hospital in Japan between February 2000 and August 2002 were studied. We evaluated the concordance rate, sensitivity, and specificity of major UCODs (cancer, heart disease, and pneumonia) reported on death certificates compared with a reference standard of pathologist assessment based on autopsy data and clinical records. Logistic regression analysis was performed to assess the effect of sex, age, comorbidity, and UCODs on misclassification.

Results

The concordance rate was relatively high for cancer (81%) but low for heart disease (55%) and pneumonia (9%). The overall concordance rate was 48%. Sex and comorbidity did not affect UCOD misclassification rates, which tended to increase with patient age, although the association with age was also not significant. The strongest factor for misclassification was UCODs (P < 0.0001). Sensitivity and specificity for cancer were very high (80% and 96%, respectively), but sensitivity for heart disease and pneumonia was 60% and 46%, respectively. Specificity for each UCOD was more than 85%.

Conclusions

Researchers should be aware of the accuracy of COD data from death certificates used as research resources, especially for cases of elderly patients with pneumonia.

High Israeli mortality rates from diabetes and renal failure - Can international comparison of multiple causes of death reflect differences in choice of underlying cause?

BACKGROUND

The age-adjusted mortality rate in Israel is low compared to most Western countries although mortality rates from diabetes and renal failure in Israel are amongst the highest, while those from cardiovascular diseases (CVD) are amongst the lowest. This study aims to assess validity of choice of underlying causes (UC) in Israel by analyzing Israeli and international data on the prevalence of these diseases as multiple causes of death (MCOD) compared to UC, and data on comorbidity (MCOD based).

METHODS

Age-adjusted death rates were calculated for UC and MCOD and the corresponding ratio of multiple to underlying cause of death (SRMU) for available years between 1999 and 2012. Comorbidity was explored by calculating cause of death association indicators (CDAI) and frequency of comorbid disease. These results were compared to data from USA, France, Italy, Australia and the Czech Republic for 2009 or other available year.

RESULTS

Mortality rates for all these diseases except renal failure have decreased in Israel between 1999 and 2012 as UC and MCOD. In 2009, the SRMU for diabetes was 2.7, slightly lower than other Western countries (3.0-3.5) showing more frequent choice as UC. Similar results were found for renal failure. In contrast, the SRMU for ischemic heart disease (IHD) and cerebrovascular disease were 2.0 and 2.6, respectively, higher than other countries (1.4-1.6 and 1.7-1.9, respectively), showing less frequent choice as UC. CDAI data showed a strong association between heart and cerebrovascular disease, and diabetes in all countries. In Israel, 40 % of deaths with UC diabetes had IHD and 24 % had cerebrovascular disease. Renal disease was less strongly associated with IHD.

CONCLUSION

This international comparison suggests that diabetes and renal failure may be coded more frequently in Israel as UC, sometimes instead of heart and cerebrovascular disease. Even with some changes in coding, mortality rates would be high compared to other countries, similar to the comparatively high diabetes prevalence in Israel at older ages and high rate of end-stage renal failure. This study highlights the importance of physician training on death certification practice and need for further progress towards automation in recording and coding death causes.

COPD-Related Mortality and Co-morbidities in Northeastern Italy, 2008-2012: A Multiple Causes of Death Analysis

INTRODUCTION

Analysis of COPD mortality based only on the underlying cause of death (UCOD) derived from death certificates underestimates disease burden. We analyzed the burden of COPD, as well as the pattern of reporting COPD and its co-morbidities in death certificates, using multiple-cause of death (MCOD) records.

METHODS

All 220,281 death certificates of decedents aged ≥ 40 years in the Veneto region (northeastern Italy) were analyzed through 2008-2012. The UCOD was selected by the Automated Classification of Medical Entities software. COPD was defined by ICD-10 codes J40-J44 and J47 based either on the UCOD or on any mention of COPD in death certificates (MCOD). Annual age-standardized COPD death rates were computed for 40-85 year-old subjects.

RESULTS

COPD was mentioned in 7.9% (and selected as the UCOD in 2.7%) of death certificates. In about half of these, COPD was mentioned in Part II only. After circulatory and neoplastic diseases, the most frequent chronic diseases reported in certificates with any mention of COPD were diabetes (15.2%) and dementia/Alzheimer (8.9%). Between 2008 and 2012, age-standardized death rates (/100,000/year) decreased from 39.8 to 34.0 in males and from 12.7 to 11.3 in females in the UCOD analyses. These trends were confirmed, although figures were three times greater, in the MCOD analyses.

CONCLUSIONS

MCOD analysis should be adopted to fully evaluate the burden of COPD-related mortality. Our findings support a decreasing trend in COPD-related mortality in northeastern Italy between 2008 and 2012, in line with other recent studies in Europe and beyond.

Multiple causes of death analysis of chronic diseases: the example of diabetes

BACKGROUND

Identifying a single disease as the underlying cause of death (UCOD) is an oversimplification of the clinical-pathological process leading to death. The multiple causes of death (MCOD) approach examines any mention of a disease in death certificates. Taking diabetes as an example, the study investigates: patterns of death certification, differences in mortality figures based on the UCOD and on MCOD, factors associated to the mention of diabetes in death certificates, and potential of MCOD in the analysis of the association between chronic diseases.

METHODS

The whole mortality archive of the Veneto Region-Italy was extracted from 2008 to 2010. Mortality rates and proportional mortality were computed for diabetes as the UCOD and as MCOD. The position of the death certificate where diabetes was mentioned was analyzed. Conditional logistic regression was applied with chronic liver diseases (CLD) as the outcome and diabetes as the exposure variable. A subset of 19,605 death certificates of known diabetic patients (identified from the archive of exemptions from medical charges) was analyzed, with mention of diabetes as the outcome and characteristics of subjects as well as other diseases reported in the certificate as predictors.

RESULTS

In the whole mortality archive, diabetes was mentioned in 12.3 % of death certificates, and selected as the UCOD in 2.9 %. The death rate for diabetes as the UCOD was 26.8 × 10(5) against 112.6 × 10(5) for MCOD; the UCOD/MCOD ratio was higher in males. The major inconsistencies of certification were entering multiple diseases per line and reporting diabetes as a consequence of circulatory diseases. At logistic regression the mention of diabetes was associated with the mention of CLD (mainly non-alcohol non-viral CLD). In the subset of known diabetic subjects, diabetes was reported in 52.1 %, and selected as the UCOD in 13.4 %. The probability of reporting diabetes was higher with coexisting circulatory diseases and renal failure and with long duration of diabetes, whereas it was lower in the presence of a neoplasm.

CONCLUSIONS

The use of MCOD makes the analysis of mortality data more complex, but conveys more information than usual UCOD analyses.

A comparison of relative and cause-specific survival by cancer site, age and time since diagnosis

Relative survival (RS) estimates are widely used by cancer registries, mainly because they do not rely on the well-documented deficiencies of cause of death information. The aim of our study was to compare 5-year cause-specific survival (CSS) estimates and 5-year RS estimates for different cancer sites by age and time since diagnosis, and discuss possible reasons for observed differences. Using data from the Cancer Registry of Norway, we identified 200,008 patients diagnosed with cancer at one of the 48 sites included in this analysis during the period 1996-2005, and followed them up until the end of 2010. CSS estimates were calculated (i) considering cause of death to be the cancer that was originally diagnosed and (ii) considering the cause of death to be a cancer within the same organ system. For most cancer sites the difference between CSS and RS estimates was small (<5%). The greatest differences were seen for rarer cancers such as mediastinum and Kaposi sarcoma. Including deaths from the same organ system in the calculation of CSS further reduced the differences for many sites. For younger age groups and shorter time since diagnosis, RS and CSS estimates tended to be similar, whereas CSS estimates tended to be lower than RS estimates with longer time since diagnosis in the oldest age groups. When compared to RS estimates CSS estimates were reliable for most of the cancer sites included in our analysis. There are, however, some exceptions where CSS estimates may not be recommended, including for rarer cancers and for patients aged 85 and above.

Does quality control of death certificates in hospitals have an impact on cause of death statistics?

BACKGROUND

The effects of inaccurate death certificates on cause of death statistics are uncertain. Since 2008, Akershus University Hospital has systematically corrected all death certificates. The effects of these corrections on the total cause of death statistics from the hospital were studied.

MATERIAL AND METHOD

ICD-10 codes for the underlying cause of death on the original and the corrected death certificates issued by Akershus University Hospital were retrieved from the Cause of Death Registry for the period 1 May 2008-31 December 2009, once the Cause of Death Registry had processed the death certificates with the aid of the computer program ACME (Automatic Classification of Medical Entities).

RESULTS

Altogether 1,001 deaths were investigated (547 men and 454 women). A total of 223 death certificates were corrected. This entailed changing the underlying cause of death in 176 cases. Death certificates for women were corrected most frequently. In 121 cases, the changes entailed a change of disease chapter in ICD-10. The corrections caused a significant reduction in the number of unspecific diagnoses, such as sepsis, cardiac arrest, pneumonia with no further specification, renal failure and fractures without any specific cause. There was a significant exchange of individuals within all the large diagnostic groups, with the exception of cancer. Because of the balancing effect of exchanges within and between the disease chapters, this generated only minor effects on general statistics on causes of death.

INTERPRETATION

The continuous correction of death certificates in the hospital was important for adjustments at the individual level and as a quality control of cause of death statistics, but had only minor effects on the general statistics from the hospital.

State differences in the reporting of diabetes-related incorrect cause-of-death causal sequences on death certificates

OBJECTIVE

To examine state differences in the reporting of diabetes-related incorrect cause-of-death (COD) causal sequences on death certificates in the U.S.

RESEARCH DESIGN AND METHODS

We conducted a cross-sectional descriptive study to determine the prevalence of two types of incorrect COD causal sequences with data from the Multiple Cause Mortality File of the year 2004.

RESULTS

Among deaths in which diabetes was reported as the first diagnosis on line a, b, c, or d in Part I of the death certificate in the U.S., 21% had below diabetes placement error (ranged from 30% in Maryland to 7% in Hawaii) and 11% had above diabetes placement error (ranged from 18% in Kentucky to 5% in California). The net effects of the two types of error ranged from -0.7% in Nevada to 19.6% in the District of Columbia.

CONCLUSIONS

Because the rates of incorrect reporting of diabetes-related COD causal sequence varied across states, the comparability of the diabetes death rate between states may have been compromised.

Modeling causes of death: an integrated approach using CODEm

BACKGROUND

Data on causes of death by age and sex are a critical input into health decision-making. Priority setting in public health should be informed not only by the current magnitude of health problems but by trends in them. However, cause of death data are often not available or are subject to substantial problems of comparability. We propose five general principles for cause of death model development, validation, and reporting.

METHODS

We detail a specific implementation of these principles that is embodied in an analytical tool - the Cause of Death Ensemble model (CODEm) - which explores a large variety of possible models to estimate trends in causes of death. Possible models are identified using a covariate selection algorithm that yields many plausible combinations of covariates, which are then run through four model classes. The model classes include mixed effects linear models and spatial-temporal Gaussian Process Regression models for cause fractions and death rates. All models for each cause of death are then assessed using out-of-sample predictive validity and combined into an ensemble with optimal out-of-sample predictive performance.

RESULTS

Ensemble models for cause of death estimation outperform any single component model in tests of root mean square error, frequency of predicting correct temporal trends, and achieving 95% coverage of the prediction interval. We present detailed results for CODEm applied to maternal mortality and summary results for several other causes of death, including cardiovascular disease and several cancers.

CONCLUSIONS

CODEm produces better estimates of cause of death trends than previous methods and is less susceptible to bias in model specification. We demonstrate the utility of CODEm for the estimation of several major causes of death.

Improper cause-of-death statements by specialty of certifying physician: a cross-sectional study in two medical centres in Taiwan

OBJECTIVE

To determine the frequency of various types of improper cause-of-death (COD) statements reported on death certificates and whether the frequency differed by specialty of the certifying physician.

DESIGN

Cross-sectional descriptive study.

SETTING

2 medical centres in Tainan, Taiwan.

PARTICIPANTS

A total of 2520 death certificates issued by 230 physicians.

MAIN OUTCOME MEASURES

4 types of improper COD statements based on the criteria of correctness of the COD causal sequence and the level of specificity of underlying COD selected.

RESULTS

Of 2520 death certificates analysed, 502 (19.9%) had at least one type of improper COD statement. However, only 235 (9.3%) sustained major errors, that is, 91 (3.6%) reported incorrect causal sequence and 144 (5.7%) reported only mechanism(s) of death (such as respiratory failure, heart failure, sepsis and acidosis). The improper reporting rate was highest among nephrologists (53%, 24/45), followed by infectious diseases physicians (45%, 29/65) and was lowest among oncologists (6%, 57/995).

CONCLUSIONS

About one-fifth issued death certificates sustained improper COD statements and only one-tenth had noteworthy errors that would threaten the quality of COD statistics. The frequency varied by specialty of the certifying physician because physicians in different specialties manage different types of diseases and conditions with contrasting complexities in terms of determining the causal sequence and specificity of COD statements.

Temporal trends in recording of diabetes on death certificates: results from Translating Research Into Action for Diabetes (TRIAD)

OBJECTIVE

To determine the frequency that diabetes is reported on death certificates of decedents with known diabetes and describe trends in reporting over 8 years.

RESEARCH DESIGN AND METHODS

Data were obtained from 11,927 participants with diabetes who were enrolled in Translating Research into Action for Diabetes, a multicenter prospective observational study of diabetes care in managed care. Data on decedents (N=2,261) were obtained from the National Death Index from 1 January 2000 through 31 December 2007. The primary dependent variables were the presence of the ICD-10 codes for diabetes listed anywhere on the death certificate or as the underlying cause of death.

RESULTS

Diabetes was recorded on 41% of death certificates and as the underlying cause of death for 13% of decedents with diabetes. Diabetes was significantly more likely to be reported on the death certificate of decedents dying of cardiovascular disease than all other causes. There was a statistically significant trend of increased reporting of diabetes as the underlying cause of death over time (P<0.001), which persisted after controlling for duration of diabetes at death. The increase in reporting of diabetes as the underlying cause of death was associated with a decrease in the reporting of cardiovascular disease as the underlying cause of death (P<0.001).

CONCLUSIONS

Death certificates continue to underestimate the prevalence of diabetes among decedents. The increase in reporting of diabetes as the underlying cause of death over the past 8 years will likely impact estimates of the burden of diabetes in the U.S.