More fun from the NYT in the spirit of Why Zebras Don’t Get Ulcers (but in this crappy economy, a hopeful tagline: Chronic stress changes the brain, but relaxation can change it back.)

http://www.nytimes.com/2009/08/18/science/18angier.html

Almost every morning on NPR there is talk of a recession.  Are we headed for a recession?  What will happen if there is a recession?  Are the markets going to fall even further?  What are people thinking about the economic stimulus packages that the government is proposing to avoid a recession?

In a recent talk about her work on risky families,  Shelley Taylor mentioned offhand that this work makes her think about recession in a new way– financial stress can place a major burden on families, which may lead to less supportive environments for children.  Is a pending recession a risk factor for depression and other health problems when children born today grow up?

One of the major findings of Taylor’s work is that the early childhood environment really matters.  The question is no longer about nature versus nurture, but rather about the interaction between an individual’s genes and his or her environment.  For example, in the case of the serotonin transporter gene, having two copies of the short allele, in combination with a negative early family environment, confers increased risk for depression and other problems.  In the context of a rich and nurturant early family environment, however, individuals with the short-short combination may actually do the best.  Researchers have conceptualized this in terms of “sensitivity to the social environment” (individuas with the short-short combo are highly sensitive to the social environment, whereas individuals with long-short or long-long may be less sensitive to the social environment and do pretty well either way).  Another good example is the MAOA gene– individuals who are low in MAOA, and who grow up in abusive contexts tend to have much higher probability of showing aggressive behavior (including violent arrests) than individuals who have high levels of MAOA or who grow up in supportive environments (see: Caspi, McClay, Moffitt, Taylor, & Craig: Role of genotype in the cycle of violence in maltreated Children.  Science. 2002).

Back to the question of a recession and its potential impact on children being born now, we don’t have data supporting or refuting this claim, but I have been thinking about the types of markers that might be able to address this type of question.  There is tons of evidence that socioeconomic status plays a major role in health, morbidity and mortality, but what does this mean for people when their financial position changes?   Will a recession now lead to more depression and health problems 20 years down the line?  Will the threat and stress of a potential recession have similar effects?

I have recently read a bunch of articles about placebo effects and pain. In the case of pain, placebo effects can be remarkable. In fact, pain-sensitive brain regions are less active when people receive pain and a placebo, compared to the equivalent pain without a placebo. Furthermore, in anticipating pain with a placebo, pre-frontal control regions are more active, which may serve to regulate the experience of pain and/ or to trigger the body’s own anti-pain medication (opioids).

Interestingly, placebo effects can be both positive (as in you feel better after taking a non-active pill, receiving an irrelevant intervention), or negative (you feel side effects from taking the pill, just as with regular meds). Also, placebo effects are often dose-response, and can have time-effect curves, and carryover effects, just like active medications.

This brings me to the topic of mind body interaction. Many people in my department study these types of effects, and certainly don’t think of them as placebo. So, where is the line between placebo and mind-body treatments? Is it just the way we label them?

As a really cool example of mind-body interaction, check out Mike Irwin’s study (press release) of immune response to the virus that causes shingles. In this study, older adults who did tai chi (meditation through movement), had higher levels of immune functioning and quality of life scores than people in a wait-list control group. Interestingly, the effects of the tai chi intervention were additive with the shingles vaccine, such that older adults who received both the tai chi intervention and the vaccine had cell-mediated immune levels comparable to those of younger adults (who are at much lower risk for getting shingles as a result).

Some other articles about pain and placebo:

Turner et al. (1994): The Importance of placebo effects in pain treatment and research.

Hrobjartsson & Gotzsche (2001): Is the placebo powerless? An analysis of clinical trials comparing placebo with no treatment.

Stewart-Williams (2004): The placebo puzzle: Putting together the pieces.

Some other articles about Mind-Body stuff:

Cruess, D. G., Antoni, M. H., McGregor, B. A., Kilbourn, K. M., Boyers, A.E., Alferi, S.M., Carver, C. S., & Kumar, M. (2000). Cognitive-behavioral stress management reduces serum cortisol by enhancing benefit finding about women being treated for early stage breast cancer. Psychosomatic Medicine, 62(3), 304-308. (4 pages)

Davidson, R.J., Kabat-Zinn, J., Schumacher, J. Rosenkranz, M., Muller, D., Santorelli, S.F., Urganowski, R., Harrington, A., Bonus, K. & Sheridan, J. F. (2003). Alterations in brain and immune function produced by mindfulness meditation. Psychosomatic Medicine, 65(4), 564-570. (6 pages)

Storch, M., Gaab, J., Kuttel, Y., Stussi, A, & Fend, H. (2007). Psychoneuroendocrine effects of resource-activating stress management training. Health Psychology, 26(4), 456-463. (7 pages)

Socioeconomic status (SES) is linked to health outcomes across a range of diseases, with increasing health at *every* level of the SES gradient (so it’s not just that being super poor is a risk factor, it’s that with every incremental increase in wealth, we see improved health).  Data suggests that in addition to the obvious culprits (access to health care, access to good food, health behaviors, etc.), stress is a major factor in SES/health disparities.

A recent article in SCAN reported one possible pathway linking SES and stress:

“after accounting for potential demographic confounds, subclinical depressive symptoms, dispositional forms of negative emotionality and conventional indicators of SES, self-reports of low subjective social status uniquely covaried with reduced gray matter volume in the perigenual area of the anterior cingulate cortex (pACC)—a brain region involved in experiencing emotions and regulating behavioral and physiological reactivity to psychosocial stress.^“

Reduced ability to regulate stress and emotion may have major health implications.

^{See also: why zebras don’t get ulcers and Naomi Eisenberger’s commentary on the article above.}

Baldwin Way wrote a really awesome primer on genetics for those of us who didn’t major in genetics or microbiology, but still want to capitalize on the power of the many new “-omics” technologies. Check it out.

As we come to the next presidential election, there is no doubt going to be a resurgence of talk about the war in Iraq and threats of terrorism. A recent study from Alison Holman and colleagues at UC Irvine suggests that people who were really stressed out by 9/11, and have ongoing worry, may be literally taking the threat to heart. The study of 2592 people showed that people who reported “ongoing worry about terrorism post 9/11″ showed a lot more physician diagnosed heart problems two and three years after the attacks than those who didn’t worry as much (risk ratios were 4.67 two years after and 3.22 three years after).

What is so nice about this study is that the authors had baseline data regarding health problems and anxiety before the attacks, and so here we get a rare, prospective look at the effect of our nation’s stress response and what that means in concrete, physical health related terms.

What is interesting, though, is that the media coverage (e.g. NYT coverage) has directly linked the government response (terror alerts) and the heart health of the population. While this may be true, the study did not assess exposure to terror alerts, or look at any mediating factors related to ongoing exposure.

The other major issue with the paper is that the authors repeatedly refer to “reports of physician diagnosed illness,” but what they are measuring is SELF-REPORTED by patients. Therefore, while the authors have done everything possible to control for confounds, and have really done an excellent job given what they had to work with, we still don’t know if what is being measured is heart disease, or whether it is anxiety that causes people to think they have heart problems (and which doctors may dignify by telling patients that they have a “racing heart”, “heart palpitations”, whatever). To their credit, the authors do point out that their measure is validated against the National Health Interview Survey (which is validated against medical charts), but I’d like to know what goes into that validation procedure.

Length of main text: 4 journal pages

Readability: 7.5/10