Physiology and Politics

Olivia Judson blogged yesterday (10/21/2008) on her NYT blog about a potential link between obesity and political attitudes. While most students and observers of politics would immediately think of a story involving health care policy (e.g. "Obese people need more expensive medical care for related chronic diseases and therefore would support candidates who lower the cost of care and increase access"), or underlying determinants of both obesity and attitudes (e.g. "If obesity is related to low income, education or being a minority, then it is desire for higher taxes, more education spending and expansion of minority rights that drives political attitudes, not obesity."). But Dr. Judson has something else in mind. Her question is: "Could the obesity epidemic have a political impact? In particular, could obesity in a pregnant woman influence the eventual political outlook of her child?" Namely, can physiology (and especially endocrinology of early development) explain political preferences? Her article is available here.

The controversy stirred up by Dr. Judson is based on evidence published last month by a team of political scientists led by Oxley at U Nebraska-Lincoln and Kevin Smith at Rice. In a small-sample experimental study of voters with "strong" political attitudes, they found out that right-wing political orientations (e.g. support for defense spending, war in Iraq, capital punishment, wire-tapping) were associated with heightened physiological responses to sudden noises and threatening visual images. The team's article, published in the journal Science, is tittled "Political Attitudes Vary with Physiological Traits," and was published by Science. Here is the abstract provided free by the journal:

Although political views have been thought to arise largely from individuals' experiences, recent research suggests that they may have a biological basis. We present evidence that variations in political attitudes correlate with physiological traits. In a group of 46 adult participants with strong political beliefs, individuals with measurably lower physical sensitivities to sudden noises and threatening visual images were more likely to support foreign aid, liberal immigration policies, pacifism, and gun control, whereas individuals displaying measurably higher physiological reactions to those same stimuli were more likely to favor defense spending, capital punishment, patriotism, and the Iraq War. Thus, the degree to which individuals are physiologically responsive to threat appears to indicate the degree to which they advocate policies that protect the existing social structure from both external (outgroup) and internal (norm-violator) threats.

Politics kills! A new study on traffic fatalities on the election day

A brilliant research report published in the Oct 2 issue of JAMA found that driving fatalities increase significantly on the election day in the US. Redelmeier from U of Toronto and Robert Tibshirani from Stanford found that the hazard of being hurt or dying in a traffic accident rises on the day of the Presidential election. While the effect seems to be bipartisan (or non-partisan?), the risk is higher for men, for those in the Northeast, and for those who vote early in the day. To my knowledge, this is the best systematic evidence that shows the dark side of political participation in the US; despite all the benefits and necessities of active participation to keep democracy alive, there also seem to be significant costs. Remember to vote, but be careful when driving or crossing the street this election season! The article was covered by Reuters and the New York Times here. The original research report is available from JAMA here and is titled "Driving Fatalities on US Presidential Election Days." Here is the free excerpt from JAMA:

The results of US presidential elections have large effects on public health by their influence on health policy, the economy, and diverse political decisions. We are unaware of studies testing whether the US presidential electoral process itself has a direct effect on public health. We hypothesized that mobilizing approximately 50% to 55% of the population, along with US reliance on motor vehicle travel, might result in an increased number of fatal motor vehicle crashes during US presidential elections.

Decline in Inequality? In the US?

There is finally some evidence that inequality in the US is declining! No, it's not income inequality, but instead inequality in the distribution of happiness. Betsey Stevenson and Justin Wolfers from the Wharton School discovered that while Americans on average have not gotten happier since the 1970s, the dispersion in happiness has declined steadily. Their NBER working paper is available here.

Here is the abstract:
This paper examines how the level and dispersion of self-reported happiness has evolved over the period 1972-2006. While there has been no increase in aggregate happiness, inequality in happiness has fallen substantially since the 1970s. There have been large changes in the level of happiness across groups: Two-thirds of the black-white happiness gap has been eroded, and the gender happiness gap has disappeared entirely. Paralleling changes in the income distribution, differences in happiness by education have widened substantially. We develop an integrated approach to measuring inequality and decomposing changes in the distribution of happiness, finding a pervasive decline in within-group inequality during the 1970s and 1980s that was experienced by even narrowly-defined demographic groups. Around one-third of this decline has subsequently been unwound. Juxtaposing these changes with large rises in income inequality suggests an important role for non-pecuniary factors in shaping the well-being distribution.

The Politics Behind Treating Combat Veterans for Brain Injuries

Traumatic Brain Injury (TBI) has emerged to the top of the list of medical conditions that have long-term consequences on US veterans.
In another in-depth look on US veterans' health, The New York Times reported a story titled "War Veterans' Concussions Are Often Overlooked." The story documents the types of long-term health costs of the war in Iraq for American soldiers once they return home. The Pentagon estimates that as many as 300,000 combat veterans have suffered at least one concussion. Of those, tens of thousands are left with long term problems such as persistent memory loss, headaches, mood swings, dizziness, hearing problems and light sensitivity. Medically, the Army classifies these as Traumatic Brain Injury (TBI). Because of high rates of under-diagnosis, the Congress ordered the Army to follow only the Veterans' Affairs new set of diagnostic tools that tend to give veterans more disability pay. The Department of Defense invested $300 million into TBI research through the Defense Centers of Excellence for Psychological Health and Traumatic Brain Injury. The very diagnosis and treatment of TBI has become an economic and public policy issue, with significant distributive effects for veterans.

Very little is known scientifically about mild traumatic brain injuries and their long-term effects, and research on the effects of combat have emerged only recently. The same New York Times article reported on Charles W. Hodge's research at the Walter Reed Army Institute. Published in the New England Journal of Medicine, and available here, the research quantified the prevalence of TBI symptoms in soldiers returning from Iraq and Afghanistan. Importantly, only 23-40 percent of those with symptoms sought any kind of mental health care. The study was also the first to find that TBI, especially when patients lose consciousness as a result of a bomb blast for example, are associated with prevalence of the post-traumatic stress disorder (PTSD), suggesting a specific neurophysiologal mechanism behind PTSD in combat veterans. Here is their abstract:

Exposure to combat was significantly greater among those who were deployed to Iraq than among those deployed to Afghanistan. The percentage of study subjects whose responses met the screening criteria for major depression, generalized anxiety, or PTSD was significantly higher after duty in Iraq (15.6 to 17.1 percent) than after duty in Afghanistan (11.2 percent) or before deployment to Iraq (9.3 percent); the largest difference was in the rate of PTSD. Of those whose responses were positive for a mental disorder, only 23 to 40 percent sought mental health care. Those whose responses were positive for a mental disorder were twice as likely as those whose responses were negative to report concern about possible stigmatization and other barriers to seeking mental health care.

Would you trust your doctors' prognosis?

Our study of doctors' prognoses showed that most doctors over-estimate their patients' chances of survival. This opens up the question of how we could improve the accuracy of prognosis and limit some of the costs patients' families and health care systems suffer when doctors make wrong prognoses. See: Alexander, M. and Christakis, N.A. "Bias and Asymmetric Loss in Expert Forecasts: A Study of Physician Prognostic Behavior with Respect to Patient Survival," Journal of Health Economics 27 (2008): 4: 1095-1108. Here is the abstract:

We study the behavioral processes undergirding physician forecasts, evaluating accuracy and systematic biases in estimates of patient survival and characterizing physicians’ loss functions when it comes to prediction. Similar to other forecasting experts, physicians face different costs depending on whether their best forecasts prove to be an overestimate or an underestimate of the true probabilities of an event. We provide the first empirical characterization of physicians’ loss functions. We find that even the physicians’ subjective belief distributions over outcomes are not well calibrated, with the loss characterized by asymmetry in favor of over-predicting patients’ survival. We show that the physicians’ bias is further increased by (1) reduction of the belief distributions to point forecasts, (2) communication of the forecast to the patient, and (3) physicians’ own past experience and reputation.

New Hampshire paper on Obama's health plan

One of the most interesting comparisons of Democrats' health plans was an editorial published by the Concord Monitor titled "Don't get sidetracked by the mandate debate." It sharply critisized the use of mandates as a substitute for offering universal health care coverage. The editorial was published a month before the New Hampshire primary, and reflects well the fact that the candidates' health care proposals may be very different in practice once implemented. Here is an excerpt:

The great health care mandate debate is a sideshow. Democratic presidential candidates Hillary Clinton and John Edwards insist that forcing individuals to buy a policy is crucial to providing universal health care or something close to it. Rival Barack Obama disagrees. A mandate may be necessary to force those who refuse to sign up once affordable options are available, he says, but that step should come at the end of the march to universal care, not at the beginning.

Doctors' empathy and cancer

A study of doctors' communication with their cancer patients found that physicians come short, on average, of listening well, and understanding, their patients' emotions. The research by Duke Medical School Professor James A. Tulsky is described in a recent feature New York Times article, "For Cancer Patients, Empathy Goes a Long Way." The study has several interesting findings, suggesting a possibility of a vicious cycle in the doctor-patient relationship. That is, physicians rarely engage their patients when they try to talk about their emotions, and the patients in turn tend to bring up their emotions surprisingly rarely. The article argues that this is relevant not only for quality of life but also for improving the odds that patients would remain compliant to their, often-long and difficult, course of therapy, with potential improvements in final treatment outcomes.