Economics and Diagnosis
Social Influence and the Autism Epidemic
Ka‐Yuet Liu, Marissa King & Peter Bearman
American Journal of Sociology, March 2010, Pages 1387-1434
Abstract:
Despite a plethora of studies, we do not know why autism incidence has increased rapidly over the past two decades. Using California data, this study shows that children living very close to a child previously diagnosed with autism are more likely to be diagnosed with autism. An underlying social influence mechanism involving information diffusion drives this result, contributing to 16% of the increase in prevalence over 2000-2005. We eliminate competing explanations (i.e., residential sorting, environmental toxicants, and viral transmission) through seven tests and show that information diffusion simultaneously contributed to the increased prevalence, spatial clustering, and decreasing age of diagnosis.
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Education, Knowledge and the Evolution of Disparities in Health
Anna Aizer & Laura Stroud
NBER Working Paper, March 2010
Abstract:
We study how advances in scientific knowledge affect the evolution of disparities in health. Our focus is the 1964 Surgeon General Report on Smoking and Health - the first widely publicized report of the negative effects of smoking on health. Using an historical dataset that includes the smoking habits of pregnant women 1959-1966, we find that immediately after the 1964 Report, more educated mothers immediately reduced their smoking as measured by both self-reports and serum cotinine levels, while the less educated did not, and that the relative health of their newborns likewise increased. We also find strong peer effects in the response to information: after the 1964 report, educated women surrounded by other educated women were more likely to reduce smoking relative to those surrounded by less educated women. Over time, the education gradient in both smoking and newborn health continued to increase, peaking in the 1980s and then shrinking, eventually returning to initial levels. These results can explain why in an era of great advancements in medical knowledge, health disparities may actually increase, at least initially.
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Low Calorie Dieting Increases Cortisol
Janet Tomiyama, Traci Mann, Danielle Vinas, Jeffrey Hunger, Jill DeJager & Shelley Taylor
Psychosomatic Medicine, forthcoming
Objective: To test the hypothesis that dieting, or the restriction of caloric intake, is ineffective because it increases chronic psychological stress and cortisol production - two factors that are known to cause weight gain; and to examine the respective roles of the two main behaviors that comprise dieting - monitoring one's caloric intake and restricting one's caloric intake - on psychological and biological stress indicators.
Methods: In a 2 (monitoring vs. not) x 2 (restricting vs. not) fully crossed, controlled experiment, 121 female participants were assigned randomly to one of four dietary interventions for 3 weeks. The monitoring + restricting condition tracked their caloric intake and restricted their caloric intake (1200 kcal/day); the monitoring only condition tracked their caloric intake but ate normally; the restricting only condition was provided 1200 kcal/day of food but did not track their calories, and the control group ate normally and did not track their intake. Before and after the interventions, participants completed measures of perceived stress and 2 days of diurnal saliva sampling to test for cortisol.
Results: Restricting calories increased the total output of cortisol, and monitoring calories increased perceived stress.
Conclusions: Dieting may be deleterious to psychological well-being and biological functioning, and changes in clinical recommendations may be in order.
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The Economics of Intense Exercise
David Meltzer & Anupam Jena
Journal of Health Economics, forthcoming
Abstract:
Despite the well-known benefits of exercise, the time required for exercise is widely understood as a major reason for low levels of exercise in the US. Intensity of exercise can change the time required for a given amount of total exercise but has never been studied from an economic perspective. We present a simple model of exercise behavior which suggests that the intensity of exercise should increase relative to time spent exercising as wages increase, holding other determinants of exercise constant. Our empirical results identify an association between income and exercise intensity that is consistent with the hypothesis that people respond to increased time costs of exercise by increasing intensity. More generally, our results suggest that time costs may be an important determinant of exercise patterns and that factors that can influence the time costs of exercise, such as intensity, may be important concerns in designing interventions to promote exercise.
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Long-Term Economic Costs of Psychological Problems During Childhood
James Patrick Smith & Gillian Smith
Social Science & Medicine, forthcoming
Abstract:
Childhood psychological conditions including depression and substance abuse are a growing concern among American children, but their long-term economic costs are unknown. This paper uses unique data from the US Panel Study of Income Dynamics (PSID) following groups of siblings and their parents for up to 40 years prospectively collecting information on education, income, work, and marriage. Following siblings offers an opportunity to control for unobserved family and neighborhood effects. A retrospective child health history designed by the author was placed into the 2007 PSID wave measuring whether respondents had any of 14 childhood physical illnesses or suffered from depression, substance abuse, or other psychological conditions. Large effects are found on the ability of affected children to work and earn as adults. Educational accomplishments are diminished, and adult family incomes are reduced by 20% or $10,400 per year with $18,000 less family household assets. Lost income is a partly a consequence of seven fewer weeks worked per year. There is also an 11 percentage point lower probability of being married. Controlling for physical childhood diseases shows that these effects are not due to the co-existence of psychological and physical diseases, and estimates controlling for within-sibling differences demonstrate that these effects are not due to unobserved common family differences. The long-term economic damages of childhood psychological problems are large - a lifetime cost in lost family income of approximately $300,000, and total lifetime economic cost for all those affected of 2.1 trillion dollars.
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Trends In Disability And Related Chronic Conditions Among People Ages Fifty To Sixty-Four
Linda Martin, Vicki Freedman, Robert Schoeni & Patricia Andreski
Health Affairs, April 2010, Pages 725-731
Abstract:
Although still below 2 percent, the proportion of people ages 50-64 who reported needing help with personal care activities increased significantly from 1997 to 2007. The proportions needing help with routine household chores and indicating difficulty with physical functions were stable. These patterns contrast with reported declines in disability among the population age sixty-five and older. Particularly concerning among those ages 50-64 are significant increases in limitations in specific mobility-related activities, such as getting into and out of bed. Musculoskeletal conditions remained the most commonly cited causes of disability at these ages. There were also substantial increases in the attribution of disability to depression, diabetes, and nervous system conditions for this age group.
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E. Fuller-Thomson, B. Yu, A. Nuru-Jeter, J. Guralnik & M. Minkler
Journals of Gerontology Series A: Biological Sciences and Medical Sciences, December 2009, Pages 1333-1336
Background: This study sought to determine whether the rates of basic activities of daily living (ADL) disabilities and functional limitations declined, remained the same, or increased between 2000 and 2005 when (a) only community-dwelling Americans aged 65 and older were examined and (b) when institutionalized older adults were included.
Method: Using data from the American Community Survey and the National Nursing Home Survey, we calculated annual prevalence rates of basic ADL disabilities and functional limitations and fitted regression lines to examine trends over time.
Results: The rates of basic ADL disabilities among community-dwelling adults aged 65 and older increased 9% between 2000 and 2005. When institutionalized elders were included, basic ADL disability rates were stable among men but increased among women. Functional limitation rates did not significantly change between 2000 and 2005.
Conclusion: These findings suggest an end of the decline in disability rates among older Americans, which, if confirmed, could have important implications for health care.
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Elliot Friedman & Pamela Herd
Psychosomatic Medicine, forthcoming
Objective: To examine the associations between income and education and three markers of inflammation: interleukin-6 (IL-6), C-reactive protein (CRP), and fibrinogen. Socioeconomic status is inversely linked with health outcomes, but the biological processes by which social position "gets under the skin" to affect health are poorly understood.
Method: Cross-sectional analyses involved participants (n = 704) from the second wave of the national population-based Survey of Midlife Development in the United States (MIDUS). Data on pretax household-adjusted income and educational attainment were collected by questionnaire and telephone interview, respectively. Detailed medical history interviews, inventories of medication, and fasting blood samples for assessment of inflammatory proteins were obtained during an overnight clinic stay.
Results: All three inflammatory proteins were inversely associated with both income and education in bivariate analyses. However, multivariate regression models, adjusting for potential confounds, showed that only low income predicted higher levels of inflammatory proteins. Moreover, inclusion of IL-6 in the regression models for CRP and fibrinogen eliminated the associations with income.
Conclusion: These results suggest that income explains the association between education and peripheral inflammation. In short, the reason that higher education is linked to reduced peripheral inflammation is because it reduces the risk for low income status, which is what is directly associated with reduced peripheral inflammation. The findings also suggest that the links between income and both CRP and fibrinogen are mediated by IL-6. These observations help to sharpen our understanding of the relationship between social position and biological markers of illness in the United States.
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Fast Food Orders in Adolescents and Young Adults: Will Menu Labeling Legislation Change Their Minds?
Andrea Garber, Jessica Wisdom, Meredith Glaser, George Lowenstein & Julie Downs
Journal of Adolescent Health, February 2010, Page S39
Purpose: As part of the policy effort to combat childhood and adolescent obesity, legislation requiring chain restaurants to provide nutrition information has been proposed at the federal level and passed in some states and municipalities. California was first to pass state-wide menu labeling legislation. Only one natural experiment has examined implementation effects, with mixed results. In experimental settings, adolescents, particularly girls, report noticing nutrition information more than adults; some order fewer calories in response while others order more. The purpose of this study was to examine real-world fast food ordering behavior among adolescents before implementation of California's menu labeling legislation.
Methods: 1500 adolescents and adults participated in this field study using anonymous surveys in two fast food chains at 9 N. CA sites that were diverse in socioeconomic status (SES). Food recall was used to assess the nutrient content of the meal just ordered. Individual factors, including age, sex, dieting and weight status, were assessed with a self-administered questionnaire. Unpaired t-tests compared groups (adolescent/young adult < 26 years to adult > 26 years old). ANOVA compared the three levels of employment with LSD post-hoc tests; multivariate ANOVA assessed overall differences in accuracy of calorie estimations.
Results: The sample was 30.7% (354/1153) adolescent/young adult (mean = 18.8 ± 3.7 years). There was no difference between the adolescent/young adults and adults in the total amount of calories (909 vs. 899, t [972] = .31) or the calories per dollar ordered (316 vs. 305, t [620] = .85). However, adolescent/young adults got more calories from drinks (14.2% vs. 11.9%, t [970] = 1.92, p = .055) and less from entrees (57.6% vs. 61.8%, t [970] = 2. 13, p = .033). They reported considering calories less (2.11 vs. 2.81 on a 1-7 scale, t [1142] = 5.41, p < .001), looking for (1.88 vs. 2.27, t [1140] = 3.29, p = .001) and seeing (2.18 vs. 2.43, t [1129] = 1.80, p = .073) less information about calories when ordering, and being less affected by calorie information in their orders (1.79 vs. 2.25, t [1132] = 3.89, p < .001). They were less accurate (F [3990] = 18.47, p < .001) and significantly underestimated (F [3990] = 19.17, p < .001) calories in standard food items and in the meal they had just ordered (t [1912] = 4.12, p < .001). The overall association between employment and calories per dollar was weak (F [2616] = 2.23, p = .11), but those who were unemployed ordered significantly more than those fully employed (322 vs. 295 calories, p = .038).
Conclusions: Adolescents and young adults are less attentive to and less knowledgeable about calorie information than adults. Those living in lower SES neighborhoods, who are more likely to be affected by unemployment, may overlook nutrition information to get more for their money. These findings indicate that this at-risk group that will require additional education and outreach to be effectively reached by menu labeling legislation.
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The Contributions of Improved Therapy and Earlier Detection to Cancer Survival Gains, 1988-2000
Eric Sun, Anupam Jena, Darius Lakdawalla, Carolina Reyes, Tomas Philipson & Dana Goldman
Forum for Health Economics & Policy, 2010
Abstract:
Prior literature has documented improvements in cancer survival over time. However, ambiguity remains over the relative contributions of improved treatment and earlier detection to survival gains. Using registry data, we developed a novel framework to estimate the relative contributions of advances in treatment and detection. Our approach compares changes in the probability of early detection, which we interpret as the effects of advances in detection, to improvements in stage-conditional survival, which we interpret as the effects of treatment. We applied this methodology using SEER data to estimate probabilities of early detection and stage-conditional survival curves for several cancers, by race, between 1988 and 2000. Survival increased for all of the cancers we examined, with blacks experiencing larger survival gains than whites for all cancers combined. Our baseline analysis found that treatment advances account for the vast majority of survival gains for all the cancers examined: breast cancer (83%), lung cancer (85%), colorectal cancer (76%), pancreatic cancer (100%), and non-Hodgkin's lymphoma (96%). Compared to whites, treatments appear to explain a lower percentage of survival gains for blacks for all cancers combined; breast cancer, NHL, and pancreatic cancer show a higher percentage of survival gains than lung cancer; and roughly the same percentage for the colorectal cancer. These results are robust to sensitivity analyses examining potential length and lead time bias. Overall, our results suggest that while improved treatment and early detection both contributed to the recent gains in survival, the majority of gains from 1988 to 2000 appear to have been driven by better treatment, manifested by improved stage-conditional survival. These results have important policy implications regarding investment in research and development and the evaluation of efforts to improve cancer screening.
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The health implications of apologizing after an adverse event
Alfred Allan & Dianne McKillop
International Journal for Quality in Health Care, April 2010, Pages 126-131
Abstract:
Australia is working towards a National Open Disclosure Standard in which all adverse incidents are disclosed to patients in all health-care facilities in the country. Among the many good reasons for this approach, one that has not attracted attention is the possibility that disclosure of an adverse incident may moderate its impact on the recovery and general health of patients. In this article, we discuss this perspective with reference to relevant psychological and physiological literature. In the absence of existing research that pursues this specific hypothesis on disclosure and health effects, we called on the extensive evidence that analogous traumatic events can lead to a prolonged state of negative affect and hyperarousal that are deleterious to recovery and health. This state is called ‘unforgiveness' by some psychologists. Research suggests that unforgiveness can be alleviated if people who feel aggrieved forgive those they blame for the harm. Forgiving is a complex process, but there is evidence that it is promoted by an apologetic response that incorporates expressions of responsibility, regret and intended action. With the exception of responsibility, these components are part of open disclosure as envisaged in the Standard. We conclude that there is preliminary support from the psychological and physiological literature for further investigation of the hypothesis that disclosure can moderate the recovery and health of patients after an adverse incident, provided that the disclosure incorporates an admission of responsibility.