Changes in Reported Dietary Supplement Use in Cognitively Normal National Alzheimer's Coordinating Center Participants Aged 55 and Older From 2015 to 2019

Abstract

Background: Although reported dietary supplement use is common in older adults, evaluations of dietary supplement use over the past 10 y are lacking.

Objective: This analysis determined changes in reported dietary supplement use in cognitively normal older adults (aged ≥ 55 y) using the National Alzheimer's Coordinating Center data from 2015 to 2019 using a serial cross-sectional study design.

Methods: The first available visit for cognitively normal participants aged ≥ 55 y from 2015 to 2019 with a complete medication form was used, resulting in 9357 participants. Associations between visit year categories and reported use of dietary supplement categories/individual supplements were tested using categorical statistics. To determine whether the probabilities of reported supplement use changed in 2019 compared with those of 2015, z-scores and two-sided P values were used. Weighted analyses were used to confirm analytical findings.

Results: When comparing 2015 and 2019, the reported use of any dietary supplement decreased from 77.7% in 2015 to 71.0% in 2019 (P < 0.0001); any vitamin from 72.5% to 65.5% (P < 0.0001); any mineral from 39.2% to 30.4% (P < 0.0001); "other" nonvitamin/nonmineral supplements from 34.4% to 26.9% (P < 0.0001), calcium from 31.2% to 21.7% (P < 0.0001), multivitamins from 48.4% to 38.4% (P < 0.0001), potassium from 5.6% to 3.5% (P = 0.001), vitamin C from 13.0% to 9.2% (P = 0.0002), chondroitin from 6.0% to 4.1% (P = 0.006), glucosamine from 11.1% to 6.5% (P < 0.0001), and all omega fatty acids from 25.2% to 17.0% (P < 0.0001). Reported use increased for vitamin B7/biotin from 3.1% in 2015 to 5.8% in 2019 (P = 0.0003), melatonin from 3.1% to 5.8% (P = 0.0002), and turmeric from 1.2% to 4.7% (P < 0.0001).

Conclusion: Although the reported use of many major dietary supplement categories and individual supplements significantly decreased in older adults from 2015 to 2019, biotin, turmeric, and melatonin significantly increased. Because biotin may interfere with some laboratory tests, this may have important public health implications.

Keywords: NACC; dietary supplement; dietary supplements; herbal; mineral; older adults; supplement; vitamins.

FIGURE 1

The process for selecting participants for reported dietary supplement analysis using the National Alzheimer’s Coordinating Center database.

FIGURE 2

Reported use of A) any dietary supplement, B) any vitamin, C) any mineral, or D) any nonvitamin nonmineral supplement in the past 14 d in the National Alzheimer’s Coordinating Center participants aged ≥ 55 y within each year from 2015 to 2019 in weighted and unweighted analyses. ∗∗∗ P < 0.0001, ∗∗ P < 0.0100. All P values reflect two-sided P values obtained from z-scores comparing the proportions of reported use of supplement categories in 2019 compared to 2015. Because P values were obtained for both weighted (circles) and unweighted (squares) analyses, the highest P value was selected.

FIGURE 3

Reported use of A) multivitamins, B) calcium, C) vitamin C, or D) biotin supplements in the past 14 d in the National Alzheimer’s Coordinating Center participants aged ≥ 55 y within each year from 2015 to 2019 in weighted and unweighted analyses. ∗∗∗ P < 0.0001, ∗∗ P < 0.0100, ∗ P < 0.05. All P values reflect two-sided P values obtained from z-scores comparing the proportions of reported use of supplement categories in 2019 compared to 2015. Since P values were obtained for both weighted (circles) and unweighted (squares) analyses, the highest P value was selected. ∗∗∗ P < 0.0001, ∗∗ P < 0.0100. All P values reflect two-sided P values obtained from z-scores comparing the proportions of reported use of supplement categories in 2019 compared to 2015. Since P values were obtained for both weighted (circles) and unweighted (squares) analyses, the highest P value was selected.

FIGURE 4

Reported use of A) all omega supplement categories, B) glucosamine, C) melatonin, or D) turmeric supplements in the past 14 d in the National Alzheimer’s Coordinating Center participants aged ≥ 55 y within each year from 2015 to 2019 in weighted and unweighted analyses.