Objectives: Although it has been shown that specific foods and nutrients are associated with sleep quality, few studies have examined the association of dietary variety and appetite with sleep quality in older adults.
Design and setting: A cross-sectional study was conducted that examined the association of dietary variety and appetite with sleep quality in Japanese adults aged ≥70 years who resided in the metropolitan area of Tokyo, Japan.
Participants: Data were collected in two steps: a mailed interview survey and an on-site survey. Those who responded to the surveys and met the inclusion criteria were included.
Measurements: Dietary variety, appetite, and sleep quality were assessed using a Dietary Variety Score (DVS), Council on Nutrition Appetite Questionnaire (CNAQ) score, and sleep efficiency, respectively. The sleep efficiency is the ratio of sleep duration to total time in bed (retiring time-awakening time). We defined the individuals with a sleep efficiency less than 75% as having poor sleep quality.
Results: Mean DVS and CNAQ score were 3.8 and 29.6 points, respectively. The rate of individuals with poor sleep quality was 11.7%. In the fully adjusted model, the odds ratios (OR) for low sleep efficiency in the middle and highest group categories of the DVS were 0.83 (95% confidence interval [CI], 0.54-1.29) and 0.50 (95% CI, 0.28-0.90), respectively, in reference to the lowest group category (p for trend = 0.023). The OR for low sleep efficiency in the middle and highest group categories of the CNAQ score were 0.73 (95% CI, 0.47-1.14) and 0.54 (95% CI, 0.30-0.96), respectively, in reference to the lowest group category (p for trend = 0.031).
Conclusions: The higher DVS and CNAQ scores were significantly associated with higher sleep efficiency. Thus, dietary variety and good appetite might help maintain good sleep quality in urban-dwelling older Japanese adults.
Keywords: Dietary variety; appetite; older Japanese adults; sleep efficiency; sleep quality.