The rate by which mortality increase with age is the same for those who experienced chronic disease as for the general population.

BACKGROUND: Mortality doubles approximately every 6-7 years during adulthood. This exponential increase in death risk with chronological age is the population-level manifestation of ageing, and often referred to as the rate-of-ageing. OBJECTIVE: We explore whether the onset of severe chronic disease alters the rate-of-ageing. METHODS: Using Swedish register data covering the entire population of the birth cohorts 1927-30, we analyse whether being diagnosed with myocardial infarction, diabetes or cancer results in a deviation of the rate-of-ageing from those of the total population. We also quantify the long-term mortality effects of these diseases, using ages with equivalent mortality levels for those with disease and the total population. RESULTS: None of the diseases revealed a sustained effect on the rate-of-ageing. After an initial switch upwards in the level of mortality, the rate-of-ageing returned to the same pace as for the total population. The time it takes for the rate to return depends on the disease. The long-term effects of diabetes and myocardial infarction amount to mortality levels that are equivalent to those aged 5-7 years older in the total population. For cancer, the level of mortality returns to that of the total population. CONCLUSION: Our results suggest an underlying process of ageing that causes mortality to increase at a set pace, with every year older we become. This process is not affected by disease history. The persistence of the rate-of-ageing motivates a critical discussion of what role disease prevention can play in altering the progression of ageing.

Disability pensions related to heavy physical workload: a cohort study of middle-aged and older workers in Sweden.

OBJECTIVES: The aim of the study was to examine the associations between heavy physical workload among middle-aged and older workers and disability pension due to any diagnosis, as well as musculoskeletal, psychiatric, cardiovascular or respiratory diagnoses. The population-based design made it possible to examine dose-response and potential gender differences in the associations. METHODS: About 1.8 million men and women aged 44-63 years and registered as living in Sweden in 2005 were followed regarding disability pension during 2006-2016, until ages 55-65 years. Mean values of physical workload and job control, estimated through gender-specific job-exposure matrices (JEMs), were assigned to individuals through their occupational titles in 2005. Exposure values were ranked separately for women and men and divided into quintiles. Associations were analyzed with Cox proportional-hazards regression. RESULTS: The analyses showed robust, dose-response associations between physical workload and disability pension with a musculoskeletal diagnosis in both genders: the adjusted hazard ratio and 95% confidence interval for those with the heaviest exposure was 2.58 (2.37-2.81) in women and 3.34 (2.83-3.94) in men. Dose-response associations were also seen in relation to disability pension with a cardiovascular or a respiratory diagnosis, though the hazard ratios were smaller. Physical workload was not associated with disability pension with a psychiatric diagnosis after adjustment for job control. CONCLUSION: This study of the entire Swedish population of middle-aged and older workers suggests that higher degrees of physical workload may increase the risk of disability pension overall, and specifically with musculoskeletal, cardiovascular or respiratory diagnosis, in both women and men.

Impact of winter holiday and government responses on mortality in Europe during the first wave of the COVID-19 pandemic.

BACKGROUND: This aggregated population study investigated the impact of the seemingly quasi-randomly assigned school winter holiday in weeks 6-10 (February to early March) on excess mortality in 219 European regions (11 countries) during the COVID-19 pandemic in the spring 2020. A secondary aim was to evaluate the impact of government responses to the early inflow of infected cases. METHODS: Data on government responses weeks 8-14 were obtained from the Oxford COVID-19 Government Response Tracker. Regional data on total all-cause mortality during weeks 14-23 in 2020 were retrieved from Eurostat and national statistical agencies and compared with the average mortality during same period 2015-2019. Variance-weighted least square regression was used with mortality difference as dependent variable with adjustment for country, population density and age distribution. RESULTS: Being a region with winter holiday exclusively in week 9 was in the adjusted analysis associated with 16 weekly excess deaths [95% confidence interval (CI) 13-20] per million inhabitants during weeks 14-23, which corresponds to 38% of the excess mortality in these regions. A more stringent response implemented in week 11, corresponding to 10 additional units on the 0-100 ordinal scale, was associated with 20 fewer weekly deaths (95% CI 18-22) per million inhabitants. CONCLUSIONS: Winter holiday in week 9 was an amplifying event that contributed importantly to the excess mortality observed in the study regions during the spring 2020. Timely government responses to the resulting early inflow of cases reduced the excess in mortality.

Trends in Hip Fracture Incidence, Recurrence, and Survival by Education and Comorbidity: A Swedish Register-based Study.

BACKGROUND: Hip fractures are common and severe conditions among older individuals, associated with high mortality, and the Nordic countries have the highest incidence rates globally. With this study, we aim to present a comprehensive picture of trends in hip fracture incidence and survival in the older Swedish population stratified by education, birth country, and comorbidity level. METHODS: This study is based on a linkage of several population registers and included the entire population over the age of 60 living in Sweden. We calculated age-standardized incidence rates for first and recurrent hip fractures as well as age-standardized proportions of patients surviving 30 and 365 days through the time period 1998 to 2017. We calculated all outcomes for men and women in the total population and in each population stratum. RESULTS: Altogether, we observed 289,603 first hip fractures during the study period. Age-standardized incidence rates of first and recurrent fractures declined among men and women in the total population and in each educational-, birth country-, and comorbidity group. Declines in incidence were more pronounced for recurrent than for first fractures. Approximately 20% of women and 30% of men died within 1 year of their first hip fracture. Overall, survival proportions remained constant throughout the study period but improved when taking into account comorbidity level. CONCLUSIONS: Hip fracture incidence has declined across the Swedish population, but mortality after hip fracture remained high, especially among men. Hip fracture patients constitute a vulnerable population group with increasing comorbidity burden and high mortality risk.

Excess mortality from COVID-19: weekly excess death rates by age and sex for Sweden and its most affected region.

BACKGROUND: Sweden has one of the highest numbers of COVID-19 deaths per inhabitant globally. However, absolute death counts can be misleading. Estimating age- and sex-specific mortality rates is necessary in order to account for the underlying population structure. Furthermore, given the difficulty of assigning causes of death, excess all-cause mortality should be estimated to assess the overall burden of the pandemic. METHODS: By estimating weekly age- and sex-specific death rates during 2020 and during the preceding 5 years, our aim is to get more accurate estimates of the excess mortality attributed to COVID-19 in Sweden, and in the most affected region Stockholm. RESULTS: Eight weeks after Sweden's first confirmed case, the death rates at all ages above 60 were higher than for previous years. Persons above age 80 were disproportionally more affected, and men suffered greater excess mortality than women in ages up to 75 years. At older ages, the excess mortality was similar for men and women, with up to 1.5 times higher death rates for Sweden and up to 3 times higher for Stockholm. Life expectancy at age 50 declined by <1 year for Sweden and 1.5 years for Stockholm compared to 2019. CONCLUSIONS: The excess mortality has been high in older ages during the pandemic, but it remains to be answered if this is because of age itself being a prognostic factor or a proxy for comorbidity. Only monitoring deaths at a national level may hide the effect of the pandemic on the regional level.

Life expectancy: what does it measure?

Life expectancy (LE) is considered a straightforward summary measure of mortality that comes with an implicit age standardisation. Thus, it has become common to present differences in mortality across populations as differences in LE, instead of, say, relative risks. However, most of the time LE does not quite provide what the term promises. LE is based on a synthetic cohort and is therefore not the true LE of anyone. Also, the implicit age standardisation is construed in such a way that it can be questioned whether it standardises age at all. In this paper, we examine LE from the point of view of its applicability to epidemiological and public health research and provide examples on the relation between an LE difference and a relative risk. We argue that the age standardisation in estimations of LE is not straightforward since it is standardised against different age distributions and that the translation of changes in age specific mortality into change in remaining LE will depend on the level and the distribution of mortality in the population. We conclude that LE is not the measure of choice in aetiological research or in research with the aim to identify risk factors of death, but that LE may be a compelling choice in public health contexts. One cannot escape the thought that the mathematical elegance of LE has contributed to its popularity.

[Covid-19 - deaths and analysis]. / Total mortalitet bättre vid jämförelser än död i covid-19.

Mortality from Covid-19 is monitored in detail and compared between countries with different strategies against the virus. There is, however, often a lack of understanding of what is required in terms of measures and interpretation to enable correct comparisons. The number of deaths from Covid-19 is affected by the testing strategy and many other things that differ between countries. Therefore, today, the most reliable source for monitoring and comparing mortality from Covid-19 is total mortality. In Sweden, there is good correspondence of Covid-19 deaths and total mortality, with a tendency to a higher total mortality indicating some under-reporting of Covid-19 mortality.

Burden and prevalence of prognostic factors for severe COVID-19 in Sweden.

The World Health Organization and European Centre for Disease Prevention and Control suggest that individuals over the age of 70 years or with underlying cardiovascular disease, cancer, chronic obstructive pulmonary disease, asthma, or diabetes are at increased risk of severe COVID-19. However, the prevalence of these prognostic factors is unknown in many countries. We aimed to describe the burden and prevalence of prognostic factors of severe COVID-19 at national and county level in Sweden. We calculated the burden and prevalence of prognostic factors for severe COVID-19 based on records from the Swedish national health care and population registers for 3 years before 1st January 2016. 9,624,428 individuals were included in the study population. 22.1% had at least one prognostic factor for severe COVID-19 (2,131,319 individuals), and 1.6% had at least three factors (154,746 individuals). The prevalence of underlying medical conditions ranged from 0.8% with chronic obstructive pulmonary disease (78,516 individuals) to 7.4% with cardiovascular disease (708,090 individuals), and the county specific prevalence of at least one prognostic factor ranged from 19.2% in Stockholm (416,988 individuals) to 25.9% in Kalmar (60,005 individuals). We show that one in five individuals in Sweden is at increased risk of severe COVID-19. When compared with the critical care capacity at a local and national level, these results can aid authorities in optimally planning healthcare resources during the current pandemic. Findings can also be applied to underlying assumptions of disease burden in modelling efforts to support COVID-19 planning.

Long-term effect of mobile phone use on sleep quality: Results from the cohort study of mobile phone use and health (COSMOS).

BACKGROUND: Effects of radiofrequency electromagnetic field exposure (RF-EMF) from mobile phone use on sleep quality has mainly been investigated in cross-sectional studies. The few previous prospective cohort studies found no or inconsistent associations, but had limited statistical power and short follow-up. In this large prospective cohort study, our aim was to estimate the effect of RF-EMF from mobile phone use on different sleep outcomes. MATERIALS AND METHODS: The study included Swedish (n = 21,049) and Finnish (n = 3120) participants enrolled in the Cohort Study of Mobile Phone Use and Health (COSMOS) with information about operator-recorded mobile phone use at baseline and sleep outcomes both at baseline and at the 4-year follow-up. Sleep disturbance, sleep adequacy, daytime somnolence, sleep latency, and insomnia were assessed using the Medical Outcome Study (MOS) sleep questionnaire. RESULTS: Operator-recorded mobile phone use at baseline was not associated with most of the sleep outcomes. For insomnia, an odds ratio (OR) of 1.24, 95% CI 1.03-1.51 was observed in the highest decile of mobile phone call-time (>258 min/week). With weights assigned to call-time to account for the lower RF-EMF exposure from Universal Mobile Telecommunications Service (UMTS, 3G) than from Global System for Mobile Communications (GSM, 2G) the OR was 1.09 (95% CI 0.89-1.33) in the highest call-time decile. CONCLUSION: Insomnia was slightly more common among mobile phone users in the highest call-time category, but adjustment for the considerably lower RF-EMF exposure from the UMTS than the GSM network suggests that this association is likely due to other factors associated with mobile phone use than RF-EMF. No association was observed for other sleep outcomes. In conclusion, findings from this study do not support the hypothesis that RF-EMF from mobile phone use has long-term effects on sleep quality.

Trends in life expectancy: did the gap between the healthy and the ill widen or close?

BACKGROUND: During the past decades, life expectancy has continued to increase in most high-income countries. Previous research suggests that improvements in life expectancy have primarily been driven by advances at the upper end of the health distribution, while parts of the population have lagged behind. Using data from the entire Swedish population, this study aims to examine the life expectancy development among subgroups of individuals with a history of common diseases relative to that of the general population. METHODS: The remaining life expectancy at age 65 was estimated for each year in 1998-2017 among individuals with a history of disease, and for the total Swedish population. We defined population subgroups as individuals with a history of myocardial infarction, ischemic or hemorrhagic stroke, hip fracture, or colon, breast, or lung cancer. We further distinguished between different educational levels and Charlson comorbidity index scores. RESULTS: Life expectancy gains have been larger for men and women with a history of myocardial infarction, ischemic or hemorrhagic stroke, and colon or breast cancer than for the general population. The life expectancy gap between individuals with a history of hip fracture or lung cancer and the general population has, however, been growing. Education and comorbidity have affected mortality levels, but have not altered the rate of increase in life expectancy among individuals with disease history. The female advantage in life expectancy was less pronounced among individuals with disease history than among the general population. CONCLUSIONS: Life expectancy has increased faster in many subpopulations with a history of disease than in the general population, while still remaining at lower levels. Improvements in life expectancy have been observed regardless of comorbidity or educational level. These findings suggest that the rise in overall life expectancy reflects more than just improved survival among the healthy or the delayed onset of disease.

Commonly used estimates of the genetic contribution to disease are subject to the same fallacies as bad luck estimates.

The scientific debate following the initial formulation of the "bad luck" hypothesis in cancer development highlighted how measures based on analysis of variance are inappropriately used for risk communication. The notion of "explained" variance is not only used to quantify randomness, but also to quantify genetic and environmental contribution to disease in heritability coefficients. In this paper, we demonstrate why such quantifications are generally as problematic as bad luck estimates. We stress the differences in calculation and interpretation between the heritability coefficient and the population attributable fraction, the estimated fraction of all disease events that would not occur if an intervention could successfully prevent the excess genetic risk. We recommend using the population attributable fraction when communicating results regarding the genetic contribution to disease, as this measure is both more relevant from a public health perspective and easier to understand.

Headache, tinnitus and hearing loss in the international Cohort Study of Mobile Phone Use and Health (COSMOS) in Sweden and Finland.

BACKGROUND: Mobile phone use and exposure to radiofrequency electromagnetic fields (RF-EMF) from it have been associated with symptoms in some studies, but the studies have shortcomings and their findings are inconsistent. We conducted a prospective cohort study to assess the association between amount of mobile phone use at baseline and frequency of headache, tinnitus or hearing loss at 4-year follow-up. METHODS: The participants had mobile phone subscriptions with major mobile phone network operators in Sweden (n = 21 049) and Finland (n = 3120), gave consent for obtaining their mobile phone call data from operator records at baseline, and filled in both baseline and follow-up questionnaires on symptoms, potential confounders and further characteristics of their mobile phone use. RESULTS: The participants with the highest decile of recorded call-time (average call-time >276 min per week) at baseline showed a weak, suggestive increased frequency of weekly headaches at 4-year follow-up (adjusted odds ratio 1.13, 95% confidence interval 0.95-1.34). There was no obvious gradient of weekly headache with increasing call-time (P trend 0.06). The association of headache with call-time was stronger for the Universal Mobile Telecommunications System (UMTS) network than older Global System for Mobile Telecommunications (GSM) technology, despite the latter involving higher exposure to RF-EMF. Tinnitus and hearing loss showed no association with call-time. CONCLUSIONS: People using mobile phones most extensively for making or receiving calls at baseline reported weekly headaches slightly more frequently at follow-up than other users, but this finding largely disappeared after adjustment for confounders and was not related to call-time in GSM with higher RF-EMF exposure. Tinnitus and hearing loss were not associated with amount of call-time.

Temporal trends in incidence, recurrence and prevalence of stroke in an era of ageing populations, a longitudinal study of the total Swedish population.

BACKGROUND: Stroke incidence has declined during the past decades. Yet, there is a concern that an ageing population together with improved survival after stroke will result in a raised proportion of the population who have experienced a stroke, as well as increasing incidence rate of recurrent strokes, and, absolute numbers of strokes. The objectives of this study were to investigate how the age specific incidence rates of recurrent strokes have developed in relation to the incidence rates of first strokes and how the postponement in age look like, and to see how the prevalence proportion of stroke as well as the absolute number of incident strokes has changed over time. METHODS: This study includes the total Swedish population born 1890-1954 living in Sweden from 1987. Stroke was identified through hospital admissions and deaths in national health registers (mandatory for all hospitals in Sweden). Age specific incidence rates were calculated for first, second, all recurrent, and all strokes for each calendar year between 1994 and 2014 for each age between 60 and 104 years. The proportion in the population with a history of stroke up to 7 years back in time was also calculated for different age groups and for different calendar years. RESULTS: Not only the incidence rate of first stroke but also of recurrent strokes have declined. The declines are evident in all ages up to 90 years of age, but not in ages above 90 years. Despite improved survival in stroke, the prevalence proportion has declined over the period and was around 3% in 2014 (somewhat higher for men than women). Even incident cases of stroke in absolute number has declined. CONCLUSIONS: Decreasing incidence rates of stroke have offset an increase in both absolute and relative numbers of stroke that otherwise would have taken place due to improved survival and an ageing population. The decline in stroke recurrence has been as strong as the decline in first strokes.

Central nervous system tumor registration in the Swedish Cancer Register and Inpatient Register between 1990 and 2014.

BACKGROUND: The Swedish Cancer Register (SCR) is characterized by excellent quality and completeness overall, but the quality of the reporting may vary according to tumor site and age, and may change over time. The aim of the current study was to investigate the completeness of the reporting of central nervous system (CNS) tumor cases to the SCR. MATERIALS AND METHODS: Individuals hospitalized for a CNS tumor between 1990 and 2014 were identified using the Inpatient Register; the proportion of identified cases that did not have any cancer diagnosis reported to the SCR was subsequently assessed. RESULTS: Between 1990 and 2014, 58,698 individuals were hospitalized for a CNS tumor, and a large proportion of them did not have any cancer diagnosis reported to the SCR (26%). This discrepancy was particularly pronounced for benign tumors and among elderly patients (over 30%). It was substantially lower for malignant brain tumors among adults (10%); moreover, no increase in the discrepancy between the two registers was observed in this group during the study period. Similar findings were found when assessing the concordance between the Cause of Death Register and the SCR. Among CNS tumor patients who were not reported to the SCR, a large proportion had only one hospital discharge diagnosis containing a CNS tumor (35%) and were less likely to be found in the Outpatient Register, which indicates that a large proportion of patients may have received an erroneous diagnosis. CONCLUSION: While a large proportion of CNS tumor patients were not reported to the SCR, the discrepancy between the SCR and the Inpatient Register was relatively small for malignant brain tumors among adults and has remained stable throughout the study period. We do not recommend that data from the Inpatient Register are combined with the SCR to estimate CNS tumor incidence, without proper confirmation of the diagnoses, as a considerable proportion of CNS tumor diagnoses registered in the Inpatient Register is unlikely to reflect true CNS tumors.

Correction: The effects of increasing longevity and changing incidence on lifetime risk differentials: A decomposition approach.

[This corrects the article DOI: 10.1371/journal.pone.0195307.].