Modern science has finally provided some information that should aid all of us in making our lifestyle decisions. If you wish to live a long and healthy life, it is far more advisable to be wealthy than to be poor. Let’s be more specific: try not to be born into poverty, and if you have inadvertently made that mistake, change your station in life ASAP.
People have long known about what is called the “socioeconomic status (SES) gradient” in health. For example, in the United States, the poorer you are, the more likely you are to get and to succumb to heart disease, respiratory disorders, ulcers, rheumatoid disorders, psychiatric diseases, or a number of types of cancer. And this is a whopper of an effect—SES accounts for at least a five-to-ten-year spread of life expectancies, and in some cases, disease or mortality risk increases more than tenfold as you go from the wealthiest to the poorest segments of our society, with things worsening each step of the way.
Naturally, there’s been some pretty energetic theorizing and investigating as to what this gradient is about.
A first obvious possibility is the issue of health-care access. Poor people are less able to afford preventative health measures, regular checkups, or the finest care that money can buy when something is wrong. That should explain a lot of what is going on. But it turns out that it doesn’t. There are robust SES health gradients in genteel, egalitarian Scandinavian countries, as there were in the old Soviet workers’ paradise (although to lesser extents in both cases than in sweaty, capitalistic Amerika). Furthermore, the SES gradient worsened in the United Kingdom over the twentieth century, despite the establishment of universal health care. And finally, the SES gradient is just as clear for a number of diseases whose prevalence are independent of preventative measures or health-care access. When it comes to these diseases (such as juvenile diabetes), you could go to the doctor for preventative checkups three times a day and, just for good measure, get centrifuged every Saturday, and that still wouldn’t change your risk. So much for limited health-care access as the cause of the SES gradient.
Another obvious factor contributing to the gradient is that the poor have too many health risks and too few health-promoting factors in their lives. This can be quite substantial. The poor are more likely to smoke, drink to excess, and to be obese. And there are also uneven distributions of living near toxic waste dumps, working in dangerous industrial occupations, being surrounded by gang warfare, on the one hand, and health-club memberships, pesticide-free veggies, and stress-reducing hobbies on the other. Yet major risk factors and protective factors of lifestyle account for only a third of the variability in the SES gradient.
Education is thought to play a role as well. Number of years of schooling is an extremely reliable correlate of SES status, raising the possibility that part of the poor health of the poor has to do with ignorance about health care and risks. Indeed, studies have shown that poorly educated people are less likely to be able to follow a complex drug regime, understand the results of something like a Pap test, or to have heard of the startling fact that smoking is not good for you. And, remarkably, new medical advances often worsen the SES gradient, simply because it is the better educated who hear about these advances, understand their significance, and understand how to access them. But despite this, education can’t be the main explanation of the SES health gradient, simply because the gradient still exists for diseases against which no stack of diplomas will protect you.
Faced with findings such as these, most in the field have come to believe that the SES gradient is predominantly about psychosocial factors—in other words, mostly about the stress of poverty. If you think that fighting your way up the corporate ladder is stressful, try having the ladder supported on your back. Psychological stress is built around a lack of control, predictability, outlets, and social support, and the poor are awash in those—layoffs whenever the economy winds down, the chance that the slumlord won’t turn on the heat just yet, the vacation that can never be afforded, and with everyone so damn tired from working two jobs, a “social support network” being yuppie jargon. And in support of this, it is diseases that are thought to be most sensitive to stress that have the steepest SES gradients (such as psychiatric disorders and heart disease). Further support for the stress connection comes from some tremendously important recent work. While objective SES is a good predictor of various measures of health, often an even better predictor is subjective SES—in other words, the most important thing is not being poor. It’s feeling poor. And as another body of key research shows, in a place like the United States, feeling poor usually means being made to feel poor—high degrees of income inequality, poverty amid plenty.
While researchers continue to understand the nuances of what causes the SES health gradient, what is undeniable is its existence and magnitude. Here’s a dramatic example of it: In one study, the health of a group of elderly nuns was examined. These women had lived together for decades, with the same medical care, diet, exposure to health dangers, and benefits. And remarkably, disease patterns and longevity were predicted by the SES of these women when they became nuns in their youth, half a century before. Whatever the gradient’s causes, poverty leaves a hell of a persistent health scar.
So again, some useful advice—try to be wealthy if you want to decrease the likelihood of most diseases. Most, but as it turns out, not all. A few diseases show an inverse SES gradient, where it is the wealthy that are more likely to get them. These diseases teach us a few things about society, the nature of illness, and, as the main point of this piece, the occasional dangers of the best medical science that money can buy.
In some cases, no one has a clue as to why a disease is more common among the wealthy. One example is an autoimmune disease, where your immune system accidentally considers a part of your body to be an alien invader and attacks it. A number of autoimmune diseases, such as rheumatoid arthritis (in which your joints are attacked), show the classic SES gradient of the poor getting hammered. But to everyone’s utter puzzlement, an inverse gradient exists for multiple sclerosis, where a part of the nervous system comes under immune attack.
For a few diseases, there are logical explanations for the inverse SES pattern. In his Theory of the Leisure Class, the sociologist Thorstein Veblen wrote about the symbols of indolent wealth in different societies. In imperial China, it was useless, bound feet. In the newly settled American West, if a rancher was sufficiently wealthy, he could afford to let some of his grazing land lie fallow and would make sure the land was conspicuously near his house, so that guests could marvel—the invention of the lawn (Veblen, unfortunately, did not live long enough to have the chance to incorporate plastic lawn flamingos into his thinking). For the wealthy nineteenth-century urbanite, the Veblenian symbol of healthful leisure was alabaster white skin. Time and society change, and at least until recently, a year-round tan had become a sign of rotisseried privilege—beach houses, ski trips, and tennis courts. As it turns out, melanoma currently shows an inverse SES gradient. People who actually work in the sun don’t get alluring whole-body tans. They get red necks. Or, as is even more often the case, they don’t get tanned much at all, given that farm workers in this country usually have a lot more melanin in their skin than do the models in ads for tanning salons.
In some cases, an inverse SES gradient is due to the glitch of its being easier to detect some versions of a disease more readily than others. Polio was long considered to be a disease of the better-off—catch a chill while yachting and you’ve got FDR in a wheelchair. Theodore Pincus of Vanderbilt Medical School has written about how this is a distortion. In actuality, the poor, typically living in much higher population densities, would contract the polio virus readily, often in the first months of life. But the key thing is that polio causes only mild and transient respiratory problems in a newborn. The poor really did get more polio. They simply got it under conditions where it wasn’t detected as such.
The primatologist Craig Packer of the University of Minnesota has reported what I consider to be a similar example of a spurious inverse SES disease…among baboons. Baboons don’t have socioeconomic status, but they sure have social status, namely dominance ranks. Being a low-ranking baboon has much in common with being a poor Westernized human, including having a disproportionate share of both physical and psychological stressors. A number of scientists, including myself, have found signs of worse health among low-ranking primates, including more stress hormones in the bloodstream, crummy immune systems, and higher blood pressure. Unexpectedly, Packer and colleagues reported an inverse gradient for miscarriages, in that higher-ranking females had the highest rate. Some colleagues of mine and I have suggested a detection problem similar to that with polio. Among the wild baboons that Packer studied, you cannot tell that a female is pregnant until she is in her second trimester (when the skin around her perineum takes on a distinctive color). Thus, by definition, this was not a case of detecting more miscarriages among higher-ranking females. This was detecting more second-or third-trimester miscarriages, something very different. Laboratory studies have shown that most primate miscarriages occur during the first trimester and are the ones that are the most stress-sensitive (as opposed to later miscarriages, which are more often related to genetic abnormalities or placental malfunction). Thus, we suggested that it is really lower-ranking females who have most of the miscarriages, but that it is simply not possible to detect this with a wild population. Not surprisingly, the two sides in this debate disagree with invigorating gusto.
But the inverse SES disease that I find to be most instructive is for real and occurs for a logical reason. It is a pediatric disease called hospitalism. It is now mostly a disease of the past, but that it ever existed constitutes an astounding and worrisome bit of medical history.
To begin to make sense of hospitalism, one must consider that in numerous traditional societies, newborns are not given names until they are a number of months or years old. This explanation is because of extremely high infant-mortality rates—wait until the child has actually managed to survive before personifying it with a name. A similar cultural adaptation could have existed early in the twentieth century in American foundling homes, institutions for abandoned or orphaned children. This was because of their staggeringly high mortality rates. In 1915, one physician, Henry Chapin, canvassed ten such places in the United States and reported numbers that didn’t require a statistician to be detected—in all but one institution, every child died before two years of age. Every child. One does not even know what to do with the sadness of this datum, reading Chapin’s stiff, mannered words some ninety years later.
And the situation at the time for children in hospitals was only somewhat less horrific. A typical child hospitalized for more than two weeks would start to show the signs of hospitalism—a listless wasting-away despite adequate food intake. Hospitalism involved weakening of muscles and loss of reflexes, and greatly increased risk of gastrointestinal and lung infections. With everything combined, mortality rates had gone up almost tenfold with the onset of hospitalism.
The savants had their guesses. Hospitals back then were dangerously unhealthy places to be, and the assumption was that with kids crammed in on pediatric wards, something infectious would be contracted. In Chapin’s era, the gastrointestinal problems got the most attention. By a decade or so later, the pulmonary problems, particularly pneumonia, were the focus. All sorts of fancy terms emerged to describe such “marantic” infants, but everyone missed the boat as to what hospitalism was about.
We now know. Hospitalism lay at the intersection of two ideas at the time—a worship of sterile, aseptic conditions at all costs, and the belief among the (overwhelmingly male) pediatric establishment that touching, holding, and nurturing infants was sentimental maternal foolishness.
Children should be seen and not heard, and if you spare the rod, you spoil the child. So the sayings used to go. While early-twentieth-century America had, for the most part, moved beyond the grim world of child labor in sweatshops, most experts’ notions of appropriate child-rearing would be considered cold and austere by today’s standards. The first decades’ equivalent of Dr. Spock, a Dr. Luther Holt of Columbia University, authored the best-selling parenting book of the time, The Care and Feeding of Children (East Norwalk, CT: Appleton-Century, fifteen editions between 1894 and 1915). In it, he warned parents of the adverse effects of the “vicious practice” of using a cradle, picking up the child when it cried, or handling the baby too often.
If parents were being told things like this, imagine how little incentive a nurse or attendant would feel to interact with a child, when confronted with a ward full of them in an orphanage or hospital. One pediatrician at Chicago’s Children’s Memorial Hospital instructed his staff to pick up and “amuse” each infant several times a day. Years later, he was still being cited as a maverick for having done so, for being an old softie so ahead of his time. And parents themselves were typically allowed only a few hours of visiting a week with an infant in a hospital.
By 1942, enough research on developmental psychology had been carried out for a correct explanation for hospitalism to be stated by a New York University physician named Harry Bakwin: “emotional deprivation.” Or, to use a technical term that he introduced to the hospitalism literature in the title of one of his publications, “loneliness.”
When an infant rat is licked and groomed by its mother, the pup secretes growth hormone, which triggers cell division—Mother’s touch is essential for normal growth. In a series of remarkable studies, Michael Meaney and colleagues at McGill University have shown that being one of the lucky rats whose mother did a whole lot of licking and grooming resulted in an array of changes in the developing brain with lifelong effects—fewer stress hormones secreted as an adult, better learning under duress, probably delayed brain aging. Similar themes have emerged from primate studies, beginning with the classic work of Harry Harlow, who showed that infant monkeys understood development better than did the average pediatrician battling hospitalism—given a choice, the monkeys preferred maternal touch to maternal nutrition. And it was not sheer tactile stimulation that was essential. Harlow dared to inject into the modern scientific literature the word love when discussing normal primate development and what was essential. And in humans, a disorder of dramatically, even fatally disrupted development due to emotional deprivation can be found in every endocrine textbook on growth. It is called psychosocial dwarfism.
The infants in hospitals, despite adequate nutrition, a sufficient number of blankets, and various medical menaces kept at bay, wasted away from emotional deprivation. And as they became depressed and listless, their immune systems were likely to weaken (as has been shown for young nonhuman primates undergoing similar deprivation). Soon they’d be falling victim to the gastrointestinal or respiratory infections so common in hospitals at the time, at which point, the feverish medical enthusiasm for aseptic isolation would kick in. The pediatricians would see the infections as a cause, rather than an effect, of hospitalism, and the kids would quickly be consigned to isolated cubicles where the goal would be their never being touched by human hands. And the mortality rate would soar.
It all makes perfect sense now, and our contemporary explanation would be incomprehensible to the concerned and competent physician of that time, for whom battling disease began and ended with the germ theory. And why was there an inverse SES gradient to hospitalism? The punch line is scattered, here and there, in these musty papers. You can almost smell the confusion on the part of these experts, as they occasionally raised the issue of an odd pattern in the statistics—kids seemed to be less likely to succumb to hospitalism in the poorer hospitals, the ones that couldn’t afford the state-of-the-art mechanical isolation boxes for marantic kids.
There are some lessons to be learned here. The specific lesson of hospitalism remains relevant. Modern medicine has developed an extraordinary ability to save premature infants, even those born months early and weighing a pound or two. But a prerequisite for such heroics is the neonatal intensive care unit, where, in the name of sterility, there remains a dearth of stimulation. In classic work done in the early 1980s, Tiffany Field of the University of Miami School of Medicine and colleagues went into such neonatology wards and started touching the kids: fifteen-minute periods, three times a day, stroking their bodies, moving their limbs. And it worked wonders. The kids grew nearly 50 percent faster, were more active and alert, matured faster behaviorally, and were released from the hospital nearly a week earlier than the premature infants who weren’t touched. Months later, they were still doing better than preemies who hadn’t been touched.
My sense is that this critical finding has yet to be implemented as widely as it could. And one does not have to look to the neonatal intensive care unit, or to ancient medical papers, to find something like hospitalism. Hold a needful, crying child in your arms, feel the comfort of comforting, feel the brief illusion that the world is a fair and safe place, and then think of warehouse stacks of children in those Romanian orphanages whose incarnations of hospitalism can take your breath away.
But there are some broader morals here. To quote Sholem Aleichem, while it’s no shame to be poor, it’s no great honor either. Try not to be poor. Maybe do something to help those who are. There’s more to health care than vanquishing germs. There’s more to normal development than adequate nutrition. And even if you’re filthy rich, you still need to use sunscreen.
And there’s a final moral, one that should sound merely cautionary, rather than like some antiscience rant. When we get sick, when a loved one does, when that inconceivable panic of mortality suddenly looms, the more proactive among us leap into action. We check the medical journals, check the health magazines, check The National Enquirer, take advantage of any connection, call that second cousin’s ex-roommate who’s the high-powered doc at the medical center—all to find out about the treatment that’s the best, the newest. And the moral there is, every now and then, not so fast—the newest isn’t always such a hot deal in medicine.
This isn’t a very practical lesson, because medical mistakes aren’t recognizable as such when they’re first introduced. It’s just useful to recall that, inevitably, once somewhere back when, a cutting-edge physician was able to inform a favorite patient about the newest—maybe it was applying a leech, maybe bleeding to release some vile humours, maybe a free sample of this new drug thalidomide. Or maybe it was the reassurance given to anxious parents that their sick child would be in a pediatric ward with all the most modern equipment.
NOTES AND FURTHER READING
The relationship between health and socioeconomic status is a huge subject and has been reviewed in these highly readable books by leaders of the field: Wilkinson R, Mind the Gap: Hierarchies, Health and Human Evolution (London: Weidenfeld and Nicolson, 2000); Marmot M, The Status Syndrome (New York: Scribner, 2004); Budrys G, Unequal Health: How Inequality Contributes to Health or Illness (Lanham, MD: Rowman & Littlefield); and Kawachi I and Kennedy B, The Health of Nations: Why Inequality Is Harmful to Your Health (New York: The New Press, 2002). A review of the field can also be found in Sapolsky R, Why Zebras Don’t Get Ulcers: A Guide to Stress, Stress-Related Diseases, and Coping, 3rd ed. (New York: Henry Holt, 2004), chap. 17.
The work on subjective SES can be found in Adler N, Epel E, Castellazzo G, and Ickovics J, “Relationship of subjective and objective social status with psychological and physiological functioning: preliminary data in healthy white women,” Health Psychology 19 (2000): 586; Goodman E, Adler N, Daniels S, Morrison J, Slap G, and Dolan L, “Impact of objective and subjective social status on obesity in a biracial cohort of adolescents,” Obesity Research 11 (2003): 1,018; and Singh-Manoux A, Adler N, Marmot MG, “Subjective social status: its determinants and its association with measures of ill-health in the Whitehall II study,” Social Science and Medicine 56 (2003): 1,321. The literature on health and income inequality is reviewed in Wilkinson, cited above.
The nun study is reported in Snowdon D, Ostwald S, and Kane R, “Education, survival and independence in elderly Catholic sisters, 1936–1988.” American Journal of Epidemiology 120 (1989): 999; and Snowdon D, Ostwald S, Kane R, and Keenan N, “Years of life with good and poor mental and physical function in the elderly,” Journal of Clinical Epidemiology 42 (1989): 1,055.
Inverse SES diseases: Multiple sclerosis: Pincus T and Callahan L, “What explains the association between socioeconomic status and health: primarily access to medical care or mind-body variables?” Advances 11 (1995): 4. Melanoma: Kitagawa E and Hauser P, Differential Mortality in the United States (Cambridge: Harvard University Press, 1973). Polio: Pincus T in Davis B, ed., Microbiology, Including Immunology and Molecular Genetics, 3rd ed. (New York: Harper and Row, 1980).
Baboons and miscarriage: see Altmann J, Sapolsky R, and Licht P, “Scientific correspondence: baboon fertility and social status,” Nature 377 (1995): 688.
The literature on hospitalism: Chapin H, “Are institutions for infants necessary?” Journal of the American Medical Association, January 2, 1915; and Chapin H, “A plea for accurate statistics in infants’ institutions,” Transactions of the American Pediatric Society 27 (1915): 180.
A review of hospitalism: Bakwin H, “Psychological aspects of pediatrics,” Journal of Pediatrics 35 (1949): 512.
Holt’s writings are discussed in Montagu A, Touching: The Human Significance of the Skin (New York: Harper and Row, 1978).
The maverick getting his staff to pick up kids: Brennemann J, “The infant ward,” American Journal of Diseases of Children 43 (1932): 577. This work is also discussed fifteen years later in Bakwin, cited above.
Loneliness as a factor in hospitalism: Bakwin H, “Loneliness in infants,” American Journal of Diseases of Children 63 (1942): 33.
Licking of rats: Kuhn C, Paul J, and Schanberg S, “Endocrine responses to mother-infant separation in developing rats,” Developmental Psychobiology 23 (1990): 395. Meaney’s work is reviewed in Meaney M, “Maternal care, gene expression, and the transmission of individual differences in stress reactivity across generations,” Annual Review of Neuroscience 24 (2001): 1,161. Harlow’s work is reported in Harlow H, “The nature of love,” American Psychologist 13 (1959): 673, and is also reviewed in a superb biography of him: Deborah Blum, Love at Goon Park: Harry Harlow and the Science of Affection (New York: Perseus Books, 2002). Psychosocial dwarfism is reviewed in chapter 6, Sapolsky, Why Zebras Don’t Get Ulcers, cited above.
Separation suppresses the immune system in nonhuman primates: Coe C, “Psychosocial factors and immunity in nonhuman primates: a review,” Psychosomatic Medicine 55 (1993): 298.
Tiffany Field’s work is reviewed in Field T, Schanberg S, Scarfidi F, and Bauer C, “Tactile kinesthetic stimulation effects on preterm neonates,” Pediatrics 77 (1986): 654.
Finally, there is now developing a scientific literature documenting just how horrendous conditions have been for development in kids in Romanian orphanages. For an entrée to this field, see Gunnar M, Mirison S, Chisholm K, and Schuder M, “Salivary cortisol levels in children adopted from Romanian orphanages,” Development and Psychopathology 13 (2001): 611. Warning: for anyone with children, this can be a heartbreakingly difficult literature to read.