Association between dietary quality and health-related quality of life among older adults: a cross-sectional study

Dietary quality is an important lifestyle factor linked to prevention of age-related diseases and functional decline, yet its contribution to health-related quality of life (HrQoL) in later life is underappreciated. We examined the association between overall dietary quality and HrQoL among community-dwelling Korean older adults.

We conducted a cross-sectional analysis of 2,104 older adults aged ≥ 65 years from the 2019-2020 Korea National Health and Nutrition Examination Survey. Dietary quality was assessed using the Korean Healthy Eating Index (KHEI), calculated from a single 24-hour dietary recall. The participants were categorized into quintile groups according to their KHEI scores. HrQoL was measured using the EuroQoL-five dimensions (EQ-5D), analyzed as an EQ-5D value and by dimension and level (i.e., any problems or no problems). We used multivariate linear regression for the EQ-5D value and multivariable logistic regression for dimension-specific outcomes, adjusting for age, sex, total energy intake, household income, education, physical activity, smoking, alcohol drinking, dietary supplement use, and the number of comorbidities.

An increasing trend was observed in the EQ-5D value with the KHEI score (P for trend = 0.009), with the highest KHEI quintile having a significantly higher EQ-5D value (mean difference: 0.03, 95% CIs: 0.011, 0.049) compared with the lowest quintile. Of the five EQ-5D dimensions (i.e., mobility, self-care, usual activities, pain/discomfort, and anxiety/depression), a significant association with KHEI was observed for mobility only; the highest KHEI quintile group had lower odds of reporting any problems in mobility (odds ratio [OR]: 0.62, 95% confidence intervals [CIs]: 0.42, 0.91) compared with the lowest quintile.

Among Korean older adults, higher dietary quality is associated with better HrQoL, potentially through reduced mobility problems. Improving dietary quality may be an effective strategy to enhance HrQoL in older age.