Screening performance of a lifestyle-based questionnaire score for vitamin D deficiency and related functional and physiological characteristics in older women

PURPOSE: This study aimed to determine if a lifestyle-based questionnaire on vitamin D can effectively screen for vitamin D deficiency in community-dwelling older women and whether such deficiency correlates with negative functional and physiological profiles. METHODS: Eighty older women completed a vitamin D questionnaire that assessed their dietary intake, sunlight exposure behaviors, and awareness of vitamin D. They also provided fasting blood samples, with serum 25-hydroxyvitamin D levels used to classify participants as deficient or non-deficient. Body composition and performance on the Senior Fitness Test (SFT) were evaluated, alongside measurements of circulating myostatin, follistatin, tumor necrosis factor-alpha, and interleukin-1 beta. Differences between groups and correlations among questionnaire scores, serum vitamin D levels, and assessed outcomes were analyzed. RESULTS: The group with vitamin D deficiency exhibited lower muscle mass, poorer muscle function, and reduced cardiorespiratory endurance compared to the non-deficient group. Additionally, the deficient group had higher levels of myostatin, lower levels of follistatin, a diminished follistatin-to-myostatin ratio, and elevated inflammatory cytokines. Positive associations were found between serum vitamin D levels and questionnaire total scores with muscle mass and functional measures, while inverse relationships were noted with myostatin and inflammatory markers. CONCLUSION: The questionnaire-based approach proved effective for identifying older women at risk for vitamin D deficiency. Combined with serum vitamin D status, it was associated with functional impairment and an unfavorable myokine-inflammatory profile. This supports the implementation of community screening to identify high-risk individuals for further testing and targeted lifestyle interventions.