To your health
"The Centers for Disease Control and Prevention estimated last year that two million people are sickened by resistant bacteria every year in the United States and 23,000 die as a result. But efforts to crack down on inappropriate antibiotic use in the United States and much of Europe have been successful, with prescriptions dropping from 2000 to 2010. That drop was more than offset, however, by growing use in the developing world. Global sales of antibiotics for human consumption rose 36 percent from 2000 to 2010, with Brazil, Russia, India, China and South Africa accounting for 76 percent of that increase." [NYT]
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The impact of early occupational choice on health behaviors
Inas Kelly et al., Review of Economics of the Household, December 2014, Pages 737-770
Abstract:
Occupational choice is a significant input into workers’ health investments, operating in a manner that can be either health-promoting or health-depreciating. Recent studies have highlighted the potential importance of initial occupational choice on subsequent outcomes pertaining to morbidity. This study is the first to assess the existence and strength of a causal relationship between initial occupational choice at labor entry and subsequent health behaviors and habits. We utilize the Panel Study of Income Dynamics to analyze the effect of first occupation, as identified by industry category and blue collar work, on subsequent health outcomes relating to obesity, alcohol misuse, smoking, and physical activity in 2005. Our findings suggest blue collar work early in life is associated with increased probabilities of obesity, at-risk alcohol consumption, and smoking, and increased physical activity later in life, although effects may be masked by unobserved heterogeneity. The weight of the evidence bearing from various methodologies, which account for non-random unobserved selection, indicates that at least part of this effect is consistent with a causal interpretation. These estimates also underscore the potential durable impact of early labor market experiences on later health.
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Mårten Palme & Emilia Simeonova, Journal of Health Economics, forthcoming
Abstract:
Breast cancer is a notable exception to the well documented positive education gradient in health. A number of studies have found that highly educated women are more likely to be diagnosed with the disease. Breast cancer is therefore often labeled as a “welfare disease”. However, it has not been established whether the strong positive correlation holds up when education is exogenously determined. We estimate the causal effect of education on the probability of being diagnosed with breast cancer by exploiting an education reform that extended compulsory schooling and was implemented as a social experiment. We find that the incidence of breast cancer increased for those exposed to the reform.
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Why Lifespans Are More Variable Among Blacks Than Among Whites in the United States
Glenn Firebaugh et al., Demography, December 2014, Pages 2025-2045
Abstract:
Lifespans are both shorter and more variable for blacks than for whites in the United States. Because their lifespans are more variable, there is greater inequality in length of life — and thus greater uncertainty about the future — among blacks. This study is the first to decompose the black-white difference in lifespan variability in America. Are lifespans more variable for blacks because they are more likely to die of causes that disproportionately strike the young and middle-aged, or because age at death varies more for blacks than for whites among those who succumb to the same cause? We find that it is primarily the latter. For almost all causes of death, age at death is more variable for blacks than it is for whites, especially among women. Although some youthful causes of death, such as homicide and HIV/AIDS, contribute to the black-white disparity in variance, those contributions are largely offset by the higher rates of suicide and drug poisoning deaths for whites. As a result, differences in the causes of death for blacks and whites account, on net, for only about one-eighth of the difference in lifespan variance.
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Socioeconomic Status, Race, and Mortality: A Prospective Cohort Study
Lisa Signorello et al., American Journal of Public Health, December 2014, Pages e98-e107
Objectives: We evaluated the independent and joint effects of race, individual socioeconomic status (SES), and neighborhood SES on mortality risk.
Methods: We conducted a prospective analysis involving 52 965 non-Hispanic Black and 23 592 non-Hispanic White adults taking part in the Southern Community Cohort Study. Cox proportional hazards modeling was used to determine associations of race and SES with all-cause and cause-specific mortality.
Results: In our cohort, wherein Blacks and Whites had similar individual SES, Blacks were less likely than Whites to die during the follow-up period (hazard ratio [HR] = 0.78; 95% confidence interval [CI] = 0.73, 0.84). Low household income was a strong predictor of all-cause mortality among both Blacks and Whites (HR = 1.76; 95% CI = 1.45, 2.12). Being in the lowest (vs highest) category with respect to both individual and neighborhood SES was associated with a nearly 3-fold increase in all-cause mortality risk (HR = 2.76; 95% CI = 1.99, 3.84). There was no significant mortality-related interaction between individual SES and neighborhood SES among either Blacks or Whites.
Conclusions: SES is a strong predictor of premature mortality, and the independent associations of individual SES and neighborhood SES with mortality risk are similar for Blacks and Whites.
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Global rise in human infectious disease outbreaks
Katherine Smith et al., Journal of the Royal Society: Interface, December 2014
Abstract:
To characterize the change in frequency of infectious disease outbreaks over time worldwide, we encoded and analysed a novel 33-year dataset (1980–2013) of 12 102 outbreaks of 215 human infectious diseases, comprising more than 44 million cases occuring in 219 nations. We merged these records with ecological characteristics of the causal pathogens to examine global temporal trends in the total number of outbreaks, disease richness (number of unique diseases), disease diversity (richness and outbreak evenness) and per capita cases. Bacteria, viruses, zoonotic diseases (originating in animals) and those caused by pathogens transmitted by vector hosts were responsible for the majority of outbreaks in our dataset. After controlling for disease surveillance, communications, geography and host availability, we find the total number and diversity of outbreaks, and richness of causal diseases increased significantly since 1980 (p < 0.0001). When we incorporate Internet usage into the model to control for biased reporting of outbreaks (starting 1990), the overall number of outbreaks and disease richness still increase significantly with time (p < 0.0001), but per capita cases decrease significantly (p = 0.005). Temporal trends in outbreaks differ based on the causal pathogen's taxonomy, host requirements and transmission mode. We discuss our preliminary findings in the context of global disease emergence and surveillance.
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Brendan Nyhan & Jason Reifler, Vaccine, 9 January 2015, Pages 459–464
Abstract:
Seasonal influenza is responsible for thousands of deaths and billions of dollars of medical costs per year in the United States, but influenza vaccination coverage remains substantially below public health targets. One possible obstacle to greater immunization rates is the false belief that it is possible to contract the flu from the flu vaccine. A nationally representative survey experiment was conducted to assess the extent of this flu vaccine misperception. We find that a substantial portion of the public (43%) believes that the flu vaccine can give you the flu. We also evaluate how an intervention designed to address this concern affects belief in the myth, concerns about flu vaccine safety, and future intent to vaccinate. Corrective information adapted from the Centers for Disease Control and Prevention (CDC) website significantly reduced belief in the myth that the flu vaccine can give you the flu as well as concerns about its safety. However, the correction also significantly reduced intent to vaccinate among respondents with high levels of concern about vaccine side effects – a response that was not observed among those with low levels of concern. This result, which is consistent with previous research on misperceptions about the MMR vaccine, suggests that correcting myths about vaccines may not be an effective approach to promoting immunization.
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Rapid Reduction in Breast Cancer Mortality with Inorganic Arsenic in Drinking Water
Allan Smith et al., EBioMedicine, November 2014, Pages 58–63
Background: Arsenic trioxide is effective in treating promyelocytic leukemia, and laboratory studies demonstrate that arsenic trioxide causes apoptosis of human breast cancer cells. Region II in northern Chile experienced very high concentrations of inorganic arsenic in drinking water, especially in the main city Antofagasta from 1958 until an arsenic removal plant was installed in 1970.
Methods: We investigated breast cancer mortality from 1950 to 2010 among women in Region II compared to Region V, which had low arsenic water concentrations. We conducted studies on human breast cancer cell lines and compared arsenic exposure in Antofagasta with concentrations inducing apoptosis in laboratory studies.
Findings: Before 1958, breast cancer mortality rates were similar, but in 1958-1970 the rates in Region II were half those in Region V (rate ratio RR = 0 • 51, 95% CI 0 • 40-0 • 66; p < 0 • 0001). Women under the age of 60 experienced a 70% reduction in breast cancer mortality during 1965-1970 (RR = 0 • 30, 0 • 17-0 • 54; p < 0 • 0001). Breast cancer cell culture studies showed apoptosis at arsenic concentrations close to those estimated to have occurred in people in Region II.
Interpretation: We found biologically plausible major reductions in breast cancer mortality during high exposure to inorganic arsenic in drinking water which could not be attributed to bias or confounding. We recommend clinical trial assessment of inorganic arsenic in the treatment of advanced breast cancer.
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The Contribution of Behavior Change and Public Health to Improved U.S. Population Health
Susan Stewart & David Cutler, NBER Working Paper, October 2014
Abstract:
Adverse behavioral risk factors contribute to a large share of deaths. We examine the effects on life expectancy (LE) and quality-adjusted life expectancy (QALE) of changes in six major behavioral risk factors over the 1960-2010 period: smoking, obesity, heavy alcohol use, and unsafe use of motor vehicles, firearms, and poisonous substances. These risk factors have moved in opposite directions. Reduced smoking, safer driving and cars, and reduced heavy alcohol use have led to health improvements, which we estimate at 1.82 years of quality-adjusted life. However, these were roughly offset by increased obesity, greater firearm deaths, and increased deaths from poisonous substances, which together reduced quality-adjusted life expectancy by 1.77 years. We model the hypothetical effects of a 50% decline in morbid obesity and in poisoning deaths, and a 10% decline in firearm fatalities, roughly matching favorable trends in smoking and increased seat belt use. These changes would lead to a 0.92 year improvement in LE and a 1.09 year improvement in QALE. Thus, substantial improvements in health by way of behavioral improvements and public health are possible.
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A.B. Nguyen, R. Moser & W.-Y. Chou, Public Health, December 2014, Pages 1076–1086
Objective: To examine the role of the social gradient on multiple health outcomes and behaviors. It was predicted that higher levels of SES, measured by educational attainment and family income, would be associated with positive health behaviors (i.e., smoking, drinking, physical activity, and diet) and health status (i.e., limited physical activity due to chronic condition, blood pressure, obesity, diabetes, BMI, and perceived health condition). The study also examined the differential effects of the social gradient in health among different racial/ethnic groups (i.e., non-Hispanic Whites, Blacks, Asian, Hispanics, and American Indians).
Methods: The data were from the adult 2009 California Health Interview Survey (CHIS). Weighted multivariable linear and logistic regression models were conducted to examine trends found between SES and health conditions and health behaviors. Polynomial trends were examined for all linear and logistic models to test for the possible effects (linear, quadratic, and cubic) of the social gradient on health behaviors and outcomes stratified by race/ethnicity.
Results: Findings indicated that, in general, Whites had more favorable health profiles in comparison to other racial/ethnic groups with the exception of Asians who were likely to be as healthy as or healthier than Whites. Predicted marginals indicated that Asians in the upper two strata of social class display the healthiest outcomes of health status among all other racial/ethnic groups. Also, the social gradient was differentially associated with health outcomes across race/ethnicity groups. While the social gradient was most consistently observed for Whites, education did not have the same protective effect on health among Blacks and American Indians. Also, compared to other minority groups, Hispanics and Asians were more likely to display curvilinear trends of the social gradient: an initial increase from low SES to mid-level SES was associated with worse health outcomes and behaviors; however, continued increase from mid-SES to high SES saw returns to healthy outcomes and behaviors.
Conclusion: The study contributes to the literature by illustrating unique patterns and trends of the social gradient across various racial/ethnic populations in a nationally representative sample. Future studies should further explore temporal trends to track the impact of the social gradient for different racial and ethnic populations in tandem with indices of national income inequalities.
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Work-Family Context and the Longevity Disadvantage of US Women
Jennifer Montez et al., Social Forces, forthcoming
Abstract:
Female life expectancy is currently shorter in the United States than in most high-income countries. This study examines work-family context as a potential explanation. While work-family context changed similarly across high-income countries during the past half century, the United States has not implemented institutional supports, such as universally available childcare and family leave, to help Americans contend with these changes. We compare the United States to Finland — a country with similar trends in work-family life but generous institutional supports — and test two hypotheses to explain US women's longevity disadvantage: (1) US women may be less likely than Finnish women to combine employment with childrearing; and (2) US women's longevity may benefit less than Finnish women's longevity from combining employment with childrearing. We used data from women aged 30–60 years during 1988–2006 in the US National Health Interview Survey Linked Mortality File and harmonized it with data from Finnish national registers. We found stronger support for hypothesis 1, especially among low-educated women. Contrary to hypothesis 2, combining employment and childrearing was not less beneficial for US women's longevity. In a simulation exercise, more than 75 percent of US women's longevity disadvantage was eliminated by raising their employment levels to Finnish levels and reducing mortality rates of non-married/non-employed US women to Finnish rates.
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Could the human papillomavirus vaccines drive virulence evolution?
Carmen Lía Murall, Chris Bauch & Troy Day, Proceedings of the Royal Society: Biological Sciences, 7 January 2015
Abstract:
The human papillomavirus (HPV) vaccines hold great promise for preventing several cancers caused by HPV infections. Yet little attention has been given to whether HPV could respond evolutionarily to the new selection pressures imposed on it by the novel immunity response created by the vaccine. Here, we present and theoretically validate a mechanism by which the vaccine alters the transmission–recovery trade-off that constrains HPV's virulence such that higher oncogene expression is favoured. With a high oncogene expression strategy, the virus is able to increase its viral load and infected cell population before clearance by the vaccine, thus improving its chances of transmission. This new rapid cell-proliferation strategy is able to circulate between hosts with medium to high turnover rates of sexual partners. We also discuss the importance of better quantifying the duration of challenge infections and the degree to which a vaccinated host can shed virus. The generality of the models presented here suggests a wider applicability of this mechanism, and thus highlights the need to investigate viral oncogenicity from an evolutionary perspective.
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Using Pay-For-Success To Increase Investment In The Nonmedical Determinants Of Health
Ian Galloway, Health Affairs, November 2014, Pages 1897-1904
Abstract:
The combination of fee-for-service payments and the US health care system’s standing commitment to treating existing illness discourages spending on the behavioral, social, and environmental (that is, the nonmedical) conditions that contribute most to long-term health. Pay-for-success, alternatively known as social impact bonds, or SIBs, offers a possible solution. The pay-for-success model relies on an investor that is willing to fund a nonmedical intervention up front while bearing the risk that the intervention may fail to prevent disease in the future. Should the intervention succeed, however, the investor is repaid in full by a predetermined payer (such as a public health agency) and receives an additional return on its investment as a reward for taking on the risk. Pay-for-success pilots are being developed to reduce asthma-related emergencies among children, poor birth outcomes, and the progression of prediabetes to diabetes, among other applications. These efforts, supported by key policy reforms such as public agency data sharing and coordinated care, promise to increase the number of evidence-based nonmedical service providers and seed a new market that values health, not just health care.
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Stefan Hansen, Diana Schendel & Erik Parner, JAMA Pediatrics, forthcoming
Objective: To quantify the effect of changes in reporting practices in Denmark on reported ASD prevalence.
Design, Setting, and Participants: We used a population-based birth cohort approach that includes information on all individuals with permanent residence in Denmark. We assessed all children born alive from January 1, 1980, through December 31, 1991, in Denmark (n = 677 915). The children were followed up from birth until ASD diagnosis, death, emigration, or the end of follow-up on December 31, 2011, whichever occurred first. The analysis uses a stratified Cox proportional hazards regression model with the changes in reporting practices modeled as time-dependent covariates.
Results: For Danish children born during the study period, 33% (95% CI, 0%-70%) of the increase in reported ASD prevalence could be explained by the change in diagnostic criteria alone; 42% (95% CI, 14%-69%), by the inclusion of outpatient contacts alone; and 60% (95% CI, 33%-87%), by the change in diagnostic criteria and the inclusion of outpatient contacts.
Conclusions and Relevance: Changes in reporting practices can account for most (60%) of the increase in the observed prevalence of ASDs in children born from 1980 through 1991 in Denmark. Hence, the study supports the argument that the apparent increase in ASDs in recent years is in large part attributable to changes in reporting practices.
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Reactive vaccination in the presence of disease hotspots
Andrew Azman & Justin Lessler, Proceedings of the Royal Society: Biological Sciences, 7 January 2015
Abstract:
Reactive vaccination has recently been adopted as an outbreak response tool for cholera and other infectious diseases. Owing to the global shortage of oral cholera vaccine, health officials must quickly decide who and where to distribute limited vaccine. Targeted vaccination in transmission hotspots (i.e. areas with high transmission efficiency) may be a potential approach to efficiently allocate vaccine, however its effectiveness will likely be context-dependent. We compared strategies for allocating vaccine across multiple areas with heterogeneous transmission efficiency. We constructed metapopulation models of a cholera-like disease and compared simulated epidemics where: vaccine is targeted at areas of high or low transmission efficiency, where vaccine is distributed across the population, and where no vaccine is used. We find that connectivity between populations, transmission efficiency, vaccination timing and the amount of vaccine available all shape the performance of different allocation strategies. In highly connected settings (e.g. cities) when vaccinating early in the epidemic, targeting limited vaccine at transmission hotspots is often optimal. Once vaccination is delayed, targeting the hotspot is rarely optimal, and strategies that either spread vaccine between areas or those targeted at non-hotspots will avert more cases. Although hotspots may be an intuitive outbreak control target, we show that, in many situations, the hotspot-epidemic proceeds so fast that hotspot-targeted reactive vaccination will prevent relatively few cases, and vaccination shared across areas where transmission can be sustained is often best.
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The relationship between gasoline price and patterns of motorcycle fatalities and injuries
He Zhu, Fernando Wilson & Jim Stimpson, Injury Prevention, forthcoming
Objective: Economic factors such as rising gasoline prices may contribute to the crash trends by shaping individuals’ choices of transportation modalities. This study examines the relationship of gasoline prices with fatal and non-fatal motorcycle injuries.
Methods: Data on fatal and non-fatal motorcycle injuries come from California's Statewide Integrated Traffic Records System for 2002–2011. Autoregressive integrated moving average (ARIMA) regressions were used to estimate the impact of inflation-adjusted gasoline price per gallon on trends of motorcycle injuries.
Results: Motorcycle fatalities and severe and minor injuries in California were highly correlated with increasing gasoline prices from 2002 to 2011 (r=0.76, 0.88 and 0.85, respectively). In 2008, the number of fatalities and injuries reached 13 457—a 34% increase since 2002, a time period in which inflation-adjusted gasoline prices increased about $0.30 per gallon every year. The majority of motorcycle riders involved in crashes were male (92.5%), middle-aged (46.2%) and non-Hispanic white (67.9%). Using ARIMA modelling, we estimated that rising gasoline prices resulted in an additional 800 fatalities and 10 290 injuries from 2002 to 2011 in California.
Conclusions: Our findings suggest that increasing gasoline prices led to more motorcycle riders on the roads and, consequently, more injuries. Aside from mandatory helmet laws and their enforcement, other strategies may include raising risk awareness of motorcyclists and investment in public transportation as an alternative transportation modality to motorcycling. In addition, universally mandated training courses and strict licensing tests of riding skills should be emphasised to help reduce the motorcycle fatal and non-fatal injuries.
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Prevalence and Costs of Skin Cancer Treatment in the U.S., 2002−2006 and 2007−2011
Gery Guy et al., American Journal of Preventive Medicine, forthcoming
Purpose: To examine trends in the treated prevalence and treatment costs of nonmelanoma and melanoma skin cancers.
Methods: This study used data on adults from the 2002−2011 Medical Expenditure Panel Survey full-year consolidated files and information from corresponding medical conditions and medical event files to estimate the treated prevalence and treatment cost of nonmelanoma skin cancer, melanoma skin cancer, and all other cancer sites. Analyses were conducted in January 2014.
Results: The average annual number of adults treated for skin cancer increased from 3.4 million in 2002−2006 to 4.9 million in 2007−2011 (p<0.001). During this period, the average annual total cost for skin cancer increased from $3.6 billion to $8.1 billion (p=0.001), representing an increase of 126.2%, while the average annual total cost for all other cancers increased by 25.1%. During 2007−2011, nearly 5 million adults were treated for skin cancer annually, with average treatment costs of $8.1 billion each year.
Conclusions: These findings demonstrate that the health and economic burden of skin cancer treatment is substantial and increasing. Such findings highlight the importance of skin cancer prevention efforts, which may result in future savings to the healthcare system.
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Christopher Herman et al., PLoS ONE, November 2014
Purpose: Recently, much media attention has been given to the premature deaths in professional wrestlers. Since no formal studies exist that have statistically examined the probability of premature mortality in professional wrestlers, we determined survival estimates for active wresters over the past quarter century to establish the factors contributing to the premature mortality of these individuals.
Methods: Data including cause of death was obtained from public records and wrestling publications in wrestlers who were active between January 1, 1985 and December 31, 2011. 557 males were considered consistently active wrestlers during this time period. 2007 published mortality rates from the Center for Disease Control were used to compare the general population to the wrestlers by age, BMI, time period, and cause of death. Survival estimates and Cox hazard regression models were fit to determine incident premature deaths and factors associated with lower survival. Cumulative incidence function (CIF) estimates given years wrestled was obtained using a competing risks model for cause of death.
Results: The mortality for all wrestlers over the 26-year study period was.007 deaths/total person-years or 708 per 100,000 per year, and 16% of deaths occurred below age 50 years. Among wrestlers, the leading cause of deaths based on CIF was cardiovascular-related (38%). For cardiovascular-related deaths, drug overdose-related deaths and cancer deaths, wrestler mortality rates were respectively 15.1, 122.7 and 6.4 times greater than those of males in the general population. Survival estimates from hazard models indicated that BMI is significantly associated with the hazard of death from total time wrestling (p<0.0001).
Conclusion: Professional wrestlers are more likely to die prematurely from cardiovascular disease compared to the general population and morbidly obese wrestlers are especially at risk. Results from this study may be useful for professional wrestlers, as well as wellness policy and medical care implementation.