Vitamin D Deficiency and Depressive Symptoms Among Rural Older Adults in South Korea: Implications for Gerontological Nursing

Purpose: To examine the association between serum 25-hydroxyvitamin D3 (25[OH]D3) levels and depressive symptoms among rural older adults in South Korea and explore implications for gerontological nursing. Method: The current cross-sectional study used 2022 national survey data from 456 rural adults aged ≥65 years. Depressive symptoms, measured using the Patient Health Questionnaire-9 (PHQ-9), and vitamin D status (<20 ng/mL vs. ≥20 ng/mL) were analyzed using adjusted logistic and linear regression. Results: Vitamin D deficiency was significantly associated with greater odds of depressive symptoms (odds ratio = 2.59, p < .001), and lower serum 25(OH)D3 levels were independently associated with higher PHQ-9 scores (β = −0.177, p < .001). Female sex was also a significant predictor. Conclusion: Vitamin D deficiency may be a modifiable factor in depression screening. Including vitamin D assessment in gerontological nursing practice may support early identification and prevention in rural older adults.