Association of dietary intake and whole blood essential trace elements with frailty in older adults: a cross-sectional study.

BACKGROUND

Both insufficient and excessive essential trace elements (ETEs) intake can have adverse effects on health.

AIMS: We aimed to evaluate the association between dietary intake and whole blood ETEs with frailty, and further explore the joint association of ETEs mixture.

METHODS

The analyses included 4,009 participants for dietary intake and 2,635 for whole blood ETEs analyses. Frailty was assessed by FRAIL scale, while dietary intake ETEs were measured by a food frequency questionnaire, and whole blood ETEs were measured using inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP-OES). We used ordinal logistic regression and restricted cubic spline (RCS) models for individual association, and weighted quantile sum (WQS) regression and quantile g-computation for joint association.

RESULTS

Increased dietary intake chromium (Cr), manganese (Mn), copper (Cu), zinc (Zn), selenium (Se) and iron (Fe) were associated with a decreased likelihood of frailty. Blood Fe (Q4 versus Q1: OR = 0.76, 95% CI: 0.61, 0.95) was negatively associated with frailty. L-shaped dose-response associations were found for dietary intake ETEs with FRAIL score, while blood Mn had a U-shaped curve, and Fe showed a negatively linear trend. In the WQS analyses, both dietary intake (β = -0.076, 95% CI: -0.122, -0.030) and blood (β = -0.078, 95% CI: -0.136, -0.020) ETEs mixtures were associated with the FRAIL score. Quantile g-computation also showed similar results.

CONCLUSIONS

Our study suggests that different ETEs play distinct roles in frailty, and supplementation needs to consider the type of ETEs and appropriate dosage.