Are Recent Cohorts Getting Worse? Trends in US Adult Physiological Status, Mental Health, and Health Behaviors Across a Century of Birth Cohorts

Abstract

Morbidity and mortality have been increasing among middle-aged and young-old Americans since the turn of the century. We investigated whether these unfavorable trends extend to younger cohorts and their underlying physiological, psychological, and behavioral mechanisms. Applying generalized linear mixed-effects models to data from 62,833 adults from the National Health and Nutrition Examination Surveys (1988-2016) and 625,221 adults from the National Health Interview Surveys (1997-2018), we found that for all sex and racial groups, physiological dysregulation has increased continuously from Baby Boomers through late-Generation X and Generation Y. The magnitude of the increase was higher for White men than for other groups, while Black men had a steepest increase in low urinary albumin (a marker of chronic inflammation). In addition, Whites underwent distinctive increases in anxiety, depression, and heavy drinking, and they had a higher level than Blacks and Hispanics of smoking and drug use in recent cohorts. Smoking is not responsible for the increasing physiological dysregulation across cohorts. The obesity epidemic contributes to the increase in metabolic syndrome but not in low urinary albumin. The worsening physiological and mental health profiles among younger generations imply a challenging morbidity and mortality prospect for the United States, one that might be particularly inauspicious for Whites.

Keywords: cohort analysis; gender disparities; health behaviors; mental health; morbidity and mortality; obesity; physiological status; racial disparities.

Figure 1

Cohort trends in expected count of physiological dysregulation, metabolic syndrome, and probability of low urinary albumin, National Health and Nutrition Examination Survey, United States, 1988–2016. The graph depicts results for White women (A), White men (B), Black women (C), Black men (D), Hispanic women (E), and Hispanic men (F). The cohort trends are labeled as follows: solid triangle with solid line, physiological dysregulation; solid circle with dotted line, metabolic syndrome; and x with dashed line, low urinary albumin. Confidence intervals are represented as the shaded area around each trend.

Figure 2

Cohort trends in expected count of depression and anxiety, National Health Interview Survey, United States, 1997–2018. The graph depicts results for White women (A), White men (B), Black women (C), Black men (D), Hispanic women (E), and Hispanic men (F). The cohort trends are labeled as follows: solid triangle with solid line, anxiety; and x with dashed line, depression. Confidence intervals are represented as the shaded area around each trend.

Figure 3

Cohort trends in heavy drinking (National Health Interview Survey, 1997–2018), ever having smoked (National Health Interview Survey, 1997–2018), and street drug use (National Health and Nutrition Examination Survey, 1988–2016), United States. The graph depicts results for White women (A), White men (B), Black women (C), Black men (D), Hispanic women (E), and Hispanic men (F). The cohort trends are labeled as follows: solid triangle with solid line, heavy drinking; solid circle with dotted line, ever smoked; and x with dashed line, street drug use. Confidence intervals are represented as the shaded area around each trend. The first two categories of birth cohorts for street drug use are combined into a single category (1931–1945, marked with ^*) due to the small sample size for the 1931–1942 cohort.

Figure 4

Cohort trends in physiological dysregulation, metabolic syndrome, and low urinary albumin (controlling vs. not controlling for smoking), National Health and Nutrition Examination Survey, United States, 1988–2016. The graph depicts results for White women (A), White men (B), Black women (C), Black men (D), Hispanic women (E), and Hispanic men (F). The cohort trends are labeled as follows: solid triangle with solid line, physiological dysregulation (not controlling for smoking); open triangle with solid line, physiological dysregulation (controlling for smoking); solid circle with dotted line, metabolic syndrome (not controlling for smoking); circled cross with dotted and dashed line, metabolic syndrome (controlling for smoking); x with dashed line, low urinary albumin (not controlling for smoking); and x inside open box with dashed line, low urinary albumin (controlling for smoking). Confidence intervals are represented as the shaded area around each trend.

Figure 5

Cohort trends in metabolic syndrome (including vs. excluding body mass index (BMI) and waist circumference), National Health and Nutrition Examination Survey, United States, 1988–2016. The graph depicts results for White women (A), White men (B), Black women (C), Black men (D), Hispanic women (E), and Hispanic men (F). The cohort trends are labeled as follows: solid triangle with solid line, metabolic syndrome (including BMI and waist circumference in index); and x with dashed line, metabolic syndrome (excluding BMI and waist circumference in index). Confidence intervals are represented as the shaded area around each trend.

Figure 6

Cohort trends in low urinary albumin (controlling vs. not controlling for body mass index (BMI) and waist circumference), National Health and Nutrition Examination Survey, United States, 1988–2016. The graph depicts results for White women (A), White men (B), Black women (C), Black men (D), Hispanic women (E), and Hispanic men (F). The cohort trends are labeled as follows: solid triangle with solid line, low urinary albumin (controlling for BMI and waist circumference); and x with dashed line, low urinary albumin (not controlling for BMI and waist circumference). Confidence intervals are represented as the shaded area around each trend.