November of the Soul

by George Howe Colt

  Although serotonin may hold the key to the enigma of suicide, serotonin dysfunction does not inevitably lead to self-destruction. Low serotonin levels are also found in people whose poor impulse control manifests itself differently—in cruelty to animals, in impulsive arson or murder, in alcoholic aggression—as well as in people who merely get highly frustrated or depressed. Furthermore, not all people who kill themselves have low serotonin; although the number varies from study to study, about 20 percent of the suicide brains Arango and her colleagues have examined have no sign of serotonin dysfunction. Furthermore, the serotonin study samples have been small, the studies have not been entirely consistent, and the results may apply to only a small segment of the population at risk for suicide—those with a history of impulsive, aggressive behavior. The evidence is not clear regarding people who complete suicide using less violent means, such as carefully hoarding sleeping pills. Given that serotonin research has been limited largely to adults, it is not yet apparent whether the connection between low serotonin and suicide extends to children and adolescents. It is also likely that the link between serotonin and suicide may be part of a larger, more intricate biochemical picture yet to be mapped. Finally, the biochemical research may help explain individual suicides, but it cannot explain fluctuating rates of suicide among different cultures and demographic groups. Few would suggest, for instance, that the nearly 300 percent rise in adolescent suicide rates from the fifties to the mideighties was due to a sudden change in the neurochemistry of children’s brains during the Eisenhower administration—or that serotonin levels are lower among the Lithuanians, with their lofty rate of suicide, than among the Greeks, with their perennially low rate.

  However incomplete the evidence, the biology of suicide clearly holds great possibilities for prevention. Although we can’t directly measure serotonin in the spinal fluid, by measuring the level of serotonin metabolites (5HIAA), it may be possible to determine who might be especially vulnerable to suicide. If those metabolites are low, Mann has suggested, the risk of suicide over the following year is four to six times higher than if those metabolites are at normal levels. But suicide is a statistically rare event. Only about one in a thousand people attempt suicide, and the number who would have to be tested to screen out those few is enormous. In addition, measuring 5HIAA requires a painful, expensive, and time-consuming spinal tap. Researchers at NYSPI are trying to develop a test that, by monitoring serotonin functioning in the prefrontal cortex, might help doctors determine which of their depressed patients are at higher risk. It is also possible that a blood test could eventually be developed that might calculate one’s chance of suicide. Such biological tests will undoubtedly aid suicide prevention efforts—and will spur the development of ever more specifically targeted medications—but they will also introduce ethical questions about how the results of those tests might be used, as well as about the psychological consequences for those who are tested.

  There are other ways of parsing the relative contributions of nature and nurture to suicide. More than thirty studies in the past several decades have found a higher rate of suicidal behavior in the family members of those who complete suicide or make a serious attempt. In a massive Danish study, published in 2002, 4,262 people between the ages of nine and forty-five who had completed suicide were compared to more than 80,000 controls. Those with a family history of suicide were two and a half times more likely to take their own lives. Furthermore, a family history of psychiatric illness increased suicide risk by some 50 percent for those without psychiatric problems; at highest risk were those whose family histories included both suicide and psychiatric illness. (Nevertheless, “suicide families” accounted for only 2 percent of all suicides, while family psychiatric history accounted for 7 percent.) As for attempted suicide, a 2002 study by psychiatrist David Brent reported that the offspring of people who attempt suicide have six times the risk of people whose parents have never attempted. The mere existence of what have been called suicide families, of course, does not establish a genetic basis for suicide. If indeed something is being passed along biologically, it may be a genetic predisposition to depression, alcoholism, or schizophrenia, all of which are strongly linked to suicide risk, rather than a genetic predisposition for suicidal behavior.

  A 1985 study of the Old Order Amish of southeastern Pennsylvania, however, suggested that what is being passed in such families might be more than vulnerability to psychiatric illness. The Amish are ideal subjects for suicide research: alcoholism, divorce, violence, unemployment, and a solitary old age, all of which are factors that have been linked to suicide, are virtually unknown among a people who live in close-knit communities governed by a strict moral code. Suicide itself is still referred to as “that awful deed” or “the abominable sin,” and until recently, Amish who killed themselves weren’t permitted burial in the community cemetery. Combing through records, Janice Egeland, a medical sociologist from the University of Miami, found that there had been twenty-six suicides among the Old Order Amish during the previous hundred years. Retrospective studies suggested that twenty-four of them could have been diagnosed with depression or manic depression—some, admittedly, on the basis of such culturally inappropriate symptoms as “racing one’s horse and carriage too hard” or “excessive use of the public telephone.” What caught Egeland’s attention was that four families accounted for 73 percent of the suicides. Interestingly, the families with the most serious cases of depression were not necessarily those with the most suicides, suggesting that some of the clustering of suicide could not be explained solely by the clustering of mood disorders.

  Another way of examining possible genetic factors is to look at twins. Identical twins, coming from the same egg, share identical genetic material. Fraternal twins, coming from two eggs, share only half their genes, making them no more similar, genetically speaking, than nontwin siblings. If there is a genetic contribution to suicide, one might expect more pairs of suicides among identical than among fraternal twins. Reviewing all the published twin studies, psychiatrist Alec Roy found nearly four hundred pairs in which at least one twin had completed suicide. Of the 129 identical pairs, 13 percent of the surviving twins completed suicide; of the 270 fraternal pairs, less than 1 percent did. Looking at attempted suicide, Roy found that nearly 40 percent of identical twins whose co-twin had completed suicide had themselves attempted suicide. No surviving fraternal twin had done so. Although suggestive, the findings fell short of proving a genetic link; the evidence for genetic influence in suicide in the twin studies was much less strong than for genetic influence of mental illness. Then, too, identical twins may share more intense psychological bonds than fraternal twins and thus, after losing a twin to suicide, might be more likely to follow suit out of either grief or the long-standing habit of parallel behavior.

  Distinguishing environmental and psychological effects from genetic contributions, however, is tricky. As with twins, the clustering of suicides within families could also be explained by modeling: when exposed to a certain behavior within a family, other members can perceive it as an option. One way to try to control for such influences is to study adoptees, who share their genes with their biological parents but their environment with their adoptive parents. If suicide has a strong genetic influence, one would expect a significantly higher suicide rate in the biological parents of adoptees who complete suicide than in the adoptive parents—which is what Danish researchers found when they examined all adoptions in Copenhagen between 1924 and 1947 and learned that fifty-seven of the adoptees eventually committed suicide. There was a significantly greater incidence of suicide in the biological relatives of suicides than in the adoptive relatives. The researchers also found that these suicides were largely independent of the presence of psychiatric disorders, leading them to suggest that there may be a genetic factor in suicide separate from the genetic transmission of mental illness.

  The Holy Grail of biological suicide research is, of course, a specific candidate ge
ne for suicidal behavior. Researchers are currently investigating polymorphisms in three genes that play critical roles in the regulation of serotonin, but have thus far found nothing conclusive.

  “Reducing suicide to a biological basis is to ignore the psychological pain which drives it,” psychologist Edwin Shneidman has said. “There can be no pill that salves the human malaise that leads to suicide.” Shneidman is among the most vocal of the mental health professionals who worry that the emphasis placed on the biology of suicide over the last few decades has slighted the psychological and sociological aspects. They don’t contest that the brain chemistry of some suicides may be skewed; it stands to reason, they say, that if someone is depressed to the point of considering suicide, his or her brain chemistry will reflect it. They suggest, however, that neurobiologists who identify serotonin dysfunction as the cause of suicidal behavior are mistaking a symptom for a disorder. “What is being measured is concomitant and not causative,” writes Shneidman. “If one (unethically) effected low levels of 5HIAA in prisoners, would they then automatically commit suicide? These biochemical values reflect inner physiological states; they are not necessarily precursors of specific behaviors.” Shneidman suggests that “what is being measured (with such precision) is general perturbation, and not specifically suicide.” The fact that suicide tends to “run” in families does not necessarily point to a genetic etiology. “French runs in families,” Shneidman has observed. “Common sense tells us that French is not inherited.”

  Indeed, the biological explanation of suicide can seem dismayingly reductive. I recall attending a conference for suicidologists in San Francisco at which Susan Blumenthal, a psychiatrist and then director of the short-lived Suicide Research Unit at NIMH, was presenting a slide show to give “an overview of our knowledge base” about adolescent suicide. Because of time restrictions, she had been asked to squeeze a presentation for which she normally allotted forty-five minutes into a fifteen-minute slot. Blumenthal spoke briskly about chemical markers, affective disorders, Marie Åsberg’s studies, and low 5HIAA as colorful slides crammed with data flashed across the screen, often so quickly that the audience was able to focus only briefly on a yellow bar here, a group of red dots there. The slides flashed faster and faster until they seemed a kaleidoscopic blur, while Blumenthal struggled to keep up, rattling off statistics with the fervor of a baseball fan reciting batting averages. I was able to decipher only scraps of her commentary: “Males would be the straight line. . . . Six times greater incidence in the biological relatives of adopted young people. . . . By no means would I suggest that all suicides are genetic. . . . People who have this finding are at twenty times greater risk of killing themselves. . . . The squares are the violent attempts by suicide, and the circles are the suicide attempts by poisoning. . . .” As I watched this hectic son et lumière, I realized I had nearly forgotten that we were talking about human beings. I thought of Justin Spoonhour and Brian Hart, of Cato and Hamlet, of Richard and Bridget Smith. I thought of the ancient Egyptian trying to convince his ba to accompany him into death, which lay before him “like the fragrance of myrrh / Like sitting under sail on breeze day.” And I wondered with some discomfort at the possibility that the answer to the question of “to be, or not to be” might all boil down to a matter of 3.5 nanograms of 5-hydroxyindoleacetic acid.

  The neurobiologists, however, reiterate that biological characteristics do not determine suicidal behavior; they merely make some individuals more susceptible to impulsive, aggressive, and possibly suicidal acts. Whether those impulses are acted on depends on a variety of social and psychological factors. “I’m not saying that suicide is purely biological,” says Arango, “but it starts with having an underlying biological risk. Having a low level of serotonin isn’t by itself enough to lead to suicide. But when mixed with other factors—psychiatric illness being foremost, but also life experience, stress, and other psychological elements—it may lead to suicide. Suicide is multifaceted. But we believe that if a person doesn’t have that biological predisposition, if he or she doesn’t have that low level of serotonin, even if all those other psychological and social factors are there, that person won’t kill himself.” In their paper “Serotonin Chemistry in the Brain of Suicidal Victims,” Arango and Underwood describe how the interaction of these ingredients might play out:

  Taking all evidence together, it is likely that suicide is not the result of a single factor but, rather, the outcome of several factors operating simultaneously at a given moment in life. For example, an individual (male) born with the biological risk for suicide (i.e., low levels of serotonin) later suffers a major depressive episode which leads to the loss of his job, heavy alcohol drinking, and marital problems. When his wife begins divorce proceedings, he becomes isolated and hopeless and kills himself. In such an example, the biological risk is present from birth, but that alone is not enough to lead the person to suicide. A psychiatric disorder (depression in this case) followed by the stressful life events (the loss of his job and the disintegration of his family), all on top of the biological risk, operates simultaneously at that specific point in time, culminating in suicide.

  “Suicide is a three-dimensional problem involving psychology, sociology, and biology,” says Herman van Praag, chairman of the department of psychiatry at the Albert Einstein College of Medicine in New York City, and a pioneer in linking low 5HIAA to severe depression and suicidal behavior. “All three are important and continuously interacting. Biology is not the sole answer. Biochemistry, for instance, cannot explain why Rembrandt is a great artist. It might explain the colors and materials he uses. It’s the same with suicide. To find out why someone is depressed, it’s very important to look at biology. But given a state of increased suicidality, the reasons why one picks up a gun, another takes a pill, and another suppresses the intention are very much caused by that person’s personality and what kind of environment he lives in. The exploration of suicide must be three-dimensional.”

  With the “medicalization of suicide,” as it has been called, some of those other dimensions have faded into the background. Nearly a century after William James—in an 1895 address to the Harvard Young Men’s Christian Association titled “Is Life Worth Living?”—called suicide a “religious disease” and its cure “religious faith,” I attended the fifteenth annual meeting of the American Association of Suicidology. On the second morning, I wandered into a workshop called “Suicide: The Challenge to the Clergy.” The panel consisted of an articulate young rabbi, a middle-aged Catholic priest, and a quiet, white-haired Episcopal minister. Each gave a short presentation on how his faith had viewed suicide throughout history. Afterward, the question-and-answer session evolved into a discussion of whether suicide was a sin. “None of us is willing to label it as a sin or crime,” said the rabbi, pointing out that in Jewish law only people who kill themselves “calmly and with clear resolve” are considered suicides, a diagnosis that allows all others to be buried. The three clergymen agreed that if people who took their own lives were declared mentally ill, they were not suicides and could therefore be buried. “An enlightened point of view,” murmured the minister.

  Several people in the audience, however, questioned the necessity of declaring a person mentally ill in order to bury him. The priest responded that “the thinking is basically for someone to act that contrary to the drive of life, they must be crazy.” There was a murmur of discomfort in the audience, which grew when he added, “Even with the terminally ill suicides, deep down you’ll find disturbance in makeup of personality.” A college chaplain in the audience maintained that some of the suicides he’d known had made calm, rational decisions. The priest replied quickly, “I don’t think anybody who is perfectly normal will commit suicide.” The Episcopal minister, sensing contention, pointed out that the presumption that a suicidal person is not in his right mind is born of compassion. But the debate continued for ten minutes. The priest became increasingly insistent. “I don’t know of anybody who has c
ommitted suicide that wasn’t a schizophrenic,” he said. A voice from the back shouted, “I don’t think it has anything to do with insanity.” The priest’s face reddened. “I’m making a judgment and you’re making a judgment,” he said, his voice digging in, “but my judgment is backed by empirical evidence.” The voice in the back replied softly, “My judgment is backed by personal experience. It happened in my family.”

  The priest’s insistence on describing suicide as proof of mental illness was unsettling; were he not wearing his clerical collar, he could have been mistaken for one of the psychiatrists presenting papers at the convention. But his stance was a reflection of how much the theological discussion of suicide has changed. As the twentieth century progressed, suicide was seen far less as a moral, ethical, or theological issue than as a medical-psychological problem. “Have we a right to commit suicide? Is it selfish to kill one’s self? Is suicide cowardly or courageous?” asked psychiatrist Gregory Zilboorg as early as 1937. “It is almost too obvious to say that whatever drawing-room or academic philosophical interest these questions may have, a scientific study of suicide must disregard them and their possible answers.” Thirty years later an editorial in the Journal of the American Medical Association asserted, “The contemporary physician sees suicide as a manifestation of emotional illness. Rarely does he view it in a context other than that of psychiatry.” The entry on suicide in the Encyclopaedia of Religion and Ethics notes, “Perhaps the greatest contribution of modern times to the rational treatment of the matter is the consideration . . . that many suicides are non-moral and entirely the affair of the specialist in mental diseases.”