Abstract
Introduction
Greater neuroticism and lower conscientiousness are linked to poorer nighttime sleep among older adults, but little is known about the association between personality and daytime sleep. Napping increases in older adulthood, and napping has been linked to health outcomes, including cognitive impairment. Thus, it is important to extend personality and sleep research to investigate napping behavior. We examined the association between personality and napping in a nationally representative cohort of older adults.
Methods
We studied 742 adults aged ≥65 years from the National Health and Aging Trends Study (NHATS) who completed the sleep and personality modules in NHATS rounds 3 or 4 (2013–2014). Personality dimensions (neuroticism, extraversion, openness, agreeableness, conscientiousness) were assessed by the Midlife Development Inventory Personality Scales. Participants reported nap frequency over the past month (most days or everyday [nappers-frequent]; some days [nappers-infrequent]; rarely/never [non-nappers]); napping intention (intentional/unintentional); and average nap duration (coded as ≤40 minutes [short]; and >40 minutes [long], consistent with previous studies). Personality dimensions were included together in all models. Model 1 adjusted for age, sex, education, and BMI, and Model 2 further adjusted for anxiety and depression, comorbidities, sleep medications, and nighttime sleep duration. Only nappers were included in models with nap frequency, intention, or duration as outcomes (n=387).
Results
There were no personality differences between nappers and non-nappers. Among nappers, however, higher neuroticism was associated with lower odds of frequent naps (OR=0.73, 95% CI: 0.55,0.97), and higher agreeableness was associated with greater odds of unintentional napping (OR=1.95, 95% CI:1.12, 3.41) and lower odds of long nap duration (OR=0.54, 95% CI:0.33, 0.90) in Model 1. Associations remained in Model 2. Higher neuroticism was also associated with greater odds of long nap duration in Model 1 (OR=1.40, 95% CI:1.03, 1.91), but not after further adjustment in Model 2.
Conclusion
This is, to our knowledge, the first study examining the association between personality and daytime napping behaviors among a large sample of older adults, extending the literature on personality and nighttime sleep in this population. Because napping behaviors are associated with health outcomes, personality may be an important factor to consider in interventions addressing napping.
Support (if any)
NIH grant 5T32MH014592-39
The Longitudinal Association Between Cardiovascular Risk and Cognitive Function in Middle-Aged and Older Adults in China: A Nationally Representative Cohort Study