The year 2005 marked the sixth year in a row of a striking increase in the suicide rate for middle-aged people in their 40s and 50s. News reports,1–3
and one previous scientific report6
have noted this trend in an age group that has previously received little attention for its risk of suicide. Although the implicit interpretation of these reports has been age-related, we explored two alternative interpretations.
One explanation is based on birth cohort membership—the upward trend may be due to the already higher suicide rates of cohorts entering midlife during this period, and may, therefore, be only a temporary increase for this age group. Another possibility is that the increase is due to social or historical events occurring during the time period—a so-called period effect. Because suicide rates increased only among those aged 40–65 years,6
however, the period effect would seem to be limited to those in middle age. Successful efforts aimed at stemming the continued increase could rest on understanding these distinctions. We sought to determine whether the increase was primarily cohort-specific, part of a larger period effect, or some combination of the two.
Compared with the voluminous scientific literature on adolescents, and to a lesser extent on elderly people, research on suicide among the middle-aged has been relatively rare. Indeed, major reports do not focus on this age group at all.7
Looking at patterns over the life course prior to 2000, age-specific suicide rates for males show a rapid increase in adolescence and young adulthood, a leveling-off or plateau for rates in middle age, and then an increase again in old age. Rates for U.S. females, albeit at a much lower absolute level than those for males, show a similar increase in adolescence and young adulthood, but in contrast to men, rates continue to rise in middle age before declining at older ages.8,9
Because of this inverted-U configuration for females, middle age is the period when male and female rates tend to be most similar, although males still have rates more than twice those of females.
Studies indicate that historically, the risk of suicide has declined among the middle-aged. Among males aged 45–64 years, rates declined from approximately 60 men per 100,000 in 1930 to fewer than 30 per 100,000 by 1986.9
Rates for females aged 45–64 years show more cyclical fluctuation, but they also decreased from about 13 women per 100,000 in 1930 to about eight per 100,000 by 1986.9
Thus, the absence of attention to suicides among the middle-aged has to some extent been due to the overall picture of stability or decline in their rates for previous decades, at the same time that more troubling increases were occurring for adolescents and the elderly.
Because of the consistent patterns revealing moderate suicide rates among middle-aged people, there has been little theoretical attention devoted to this period of the life course. Some have applied Durkheim's theory of suicide—that the nature of individuals' ties to society affects the risk of suicide10,11
—to explain the middle-aged pattern of stability in suicide rates among men. One study,12
for example, observed that middle-aged males are normatively in the midst of their family and work lives, at their peak of social integration, and, hence, at a lower risk of suicide than they were before these midlife levels of achievement were reached or than they will be when the losses of old age emerge. Among women, by the 1980s, the mid-century pattern of family orientation had given way to labor-force participation levels much more like those of men.9
To the extent that recent social role, economic, or other changes have eroded these traditional midlife protections for both males and females, they provide a period explanation for the post-1999 surge in suicide rates.
A cohort explanation, by contrast, would suggest that the recently observed higher rates represent a suicide risk carried uniquely by those cohorts now occupying middle age. People aged 40–49 and 50–59 years in 2005 were born between 1946 and 1964, the postwar baby boom cohort birth years. This cohort, especially males, had notably high rates of suicide while in adolescence.13
Writing in the mid-1980s, scholars14,15
drew attention to the birth cohort membership of those with the newly high rates and predicted continued high rates, arguing that those in exceptionally large cohorts are subject to a number of disadvantages that persist throughout the life course, such as greater competition for limited resources (e.g., in schools and the labor market). Others adopted a psychological/cultural approach16
rather than using cohort size as a mechanism, or emphasized generational identity17
or the high rates of depression18,19
and substance abuse20
among baby boomers, but all noted that something about cohort membership put this group at a continued high risk for the future. Thus, there have been previous cohort-based interpretations of the high adolescent suicide rates for those presently in middle age.
In this article, we explored whether the steady increase in suicides since 1999 among the middle-aged is more characteristic of possible period effects or of birth-cohort membership. A previous report showed that the increase is limited to white males and females, with no evidence of increases among African Americans or other racial/ethnic groups.6
Thus, we examined patterns by gender, education, and marital status, but not by race/ethnicity, to see how widespread the increases are and if any groups are at particularly high risk.