Relationship of zinc status with depression and anxiety among elderly population

Background & aims: Population aging is a global challenge. Old populations are prone to zinc deficiency. This study aimed to determine the association of zinc status with depression and anxiety among men and women aged 60+ years old.

Methods: In this cross-sectional study, 297 elderly participants (144 males and 153 females) were studied. The dietary and serum zinc were assessed using a three-day dietary record and an auto-analyzer, respectively. Depression and anxiety were measured using Geriatric Depression Scale and Hamilton Anxiety Rating Scale, respectively. Chi-squared test was used to compare qualitative variables. Multiple logistic regression analysis was conducted to assess relationship between zinc status and depression/anxiety.

Results: The total zinc deficiency based on serum values was 23.2%. Dietary intake of zinc in 72.4%of participants was less than of the Estimated Average Requirement (EAR). The total depression prevalence was 42.2%. Moreover, 52.5% of the participants suffered from anxiety. The odds of depression among participants in the third tertile of serum zinc concentration was 51% lower than those in the first tertile (OR = 0.49, CI = 0.25-0.96, p = 0.03). No significant relationship was found between zinc intake and depression. Furthermore, serum or dietary zinc levels were not related to anxiety.

Conclusions: This study showed a considerable zinc deficiency and depression/anxiety in the old population. A significant relation was found between serum zinc concentration and depression. Further surveys, especially cohort studies and clinical trials are needed to confirm these results.