摘要：Objectives. We examined whether attaining a higher educational degree after 25 years of age was associated with fewer depressive symptoms and better self-rated health at midlife than was not attaining a higher educational degree. Methods. We analyzed data from National Longitudinal Survey of Youth, restricting our sample to respondents who had not attained a bachelor's degree by 25 years of age (n = 7179). We stratified all regression models by highest degree attained by 25 years of age. Results. Among respondents with no degree, a high school diploma, or a post–high school certificate at 25 years of age, attaining at least a bachelor's degree by midlife was associated with fewer depressive symptoms and better self-rated health at midlife compared with respondents who did not attain a higher degree by midlife. Those with an associate's degree at 25 years of age who later attained a bachelor's degree or higher reported better health at midlife. Conclusions. Attaining at least a bachelor's degree after 25 years of age is associated with better midlife health. Other specifications of educational timing and its health effects across the life course should be studied. With increasing education, individuals experience more favorable health 1–5 and greater longevity. 6–9 Yet, much of the research implicitly, and sometimes explicitly, assumes that education is completed at or around 25 years of age and is stable thereafter. 8–12 As such, education–health research often ignores issues of educational timing, even though US educational pathways became much more differentiated after the 1970s as women entered the labor force in greater numbers, the economy shifted from industrial to service-based, higher education became more affordable, and a college degree became necessary to attain a middle-class lifestyle. 13–15 For example, in 1970, 28% of US undergraduate students were 25 years or older. 16 By 2008, the percentage had increased to 38%. 17 The number of individuals returning to school when older than 25 years is projected to increase from 6.9 million in 2006 to 8.1 million by 2017. 18 Given that a significant proportion of US adults earn a college degree after their mid-20s, it is surprising that few studies have examined the health effects of returning to school later in life. Attaining a higher degree after the mid-20s may result in positive mental and physical health benefits for US adults. Regardless of the age at which one returns to school, educational activities can enhance social networks, provide individuals with fulfilling life experiences, and foster adult development and intellectual enrichment. 19 Such experiences may be particularly important for mental health. For example, 1 study found that individuals who attained their general educational development (GED) certificate in adulthood had lower levels of depressive symptoms than did permanent high school dropouts. 20 Additionally, individuals who attain a higher degree after their mid-20s can experience increases in their earnings and more stable employment, 21 which in turn may promote better mental and physical health. For example, Clark and Jaeger 21 found that high school dropouts who attained their GED certificate in adulthood experienced wages closer to individuals who attained a high school diploma at the end of 12th grade than to permanent dropouts. Alternatively, returning to school later in life may have little or no effect on health. Because individuals who attain their college degree later in adulthood have fewer years in the labor market to recoup their investment in education, they may be less likely to accumulate the economic and social (e.g., personal control, cognitive ability, and moral reasoning) 4,22 benefits associated with a college degree that may lead to better psychological and physical functioning. For example, Taniguchi reported that individuals who completed a bachelor's degree when 25 years or older received significantly lower wages than did those who received a bachelor's degree before 25 years of age. 23 Importantly, however, Taniguchi did not consider whether those who attained a college degree when 25 years or older received any economic benefit to their delayed degree completion. That is, attaining a bachelor's degree later in life may still yield economic benefits in comparison with never receiving a bachelor's degree. Given that 2 of the most important mechanisms linking education to health are employment and wages, 24–26 it is important to consider whether the timing of education contributes to health at midlife among US adults, as it seems to have some effect on wages. This question is especially timely as US policymakers tout retraining unemployed, often older or less educated workers as a viable strategy to help affected workers find new work. Our study advances current research on the education–health relationship by exploring the extent to which attaining a higher degree after the mid-20s is associated with depressive symptoms and self-rated health at midlife. We chose depressive symptoms and self-rated health for 2 reasons. First, the few studies to have examined the effect of the timing of education on health have focused on depressive symptoms or psychological well-being. Second, self-rated health is commonly used in education–health research 1,4,24,27 and is a valid and reliable measure of subjective well-being that correlates strongly with physician assessments of morbidity and subsequent mortality. 28–30 We hypothesized that among US adults who had attained less than a bachelor's degree by their mid-20s, attaining a higher degree by midlife would be associated with fewer depressive symptoms and better self-rated health compared with those who maintain their level of education after their mid-20s and that attaining at least a bachelor's degree after the mid-20s would provide greater health benefits than would attaining a lesser degree after the mid-20s. It is likely, however, that attaining at least a bachelor's degree after the mid-20s will provide greater health benefits than will attaining a lesser degree after the mid-20s, given the strong association of a college or advanced degree with employment options, occupational prestige, and wages. 31
