Ethnic differences in herb and vitamin/mineral use in the elderly

BACKGROUND: Little information exists on herb and vitamin-mineral supplement use in very old people and whether use varies by ethnicity. OBJECTIVE: To examine the prevalence and predictors of herb and vitamin-mineral supplement use in a tri-ethnic sample of adults aged > or = 77 years. METHODS: In-home interviews in 1997-1998 assessed medications use and sociodemographic and health factors in community-dwelling elderly non-Hispanic white (n = 125), black (n = 112), and Hispanic (n = 128) adults. RESULTS: Of the 365 subjects (71.5% > or = 80 y old, 52.6% female), 172 reported using at least one of the preparations (vitamin-mineral supplements 132, herbs alone 21, both herbs and vitamin-mineral supplements 19). Herbal use varied by ethnicity: 12.8% in non-Hispanic whites, 16.1% in blacks, and 4.7% in Hispanics. The most commonly used herbs were garlic, Ginkgo biloba, saw palmetto, and vinegar. Use of vitamin-mineral supplements, alone or combined with herbs, also varied by ethnicity: 54.4% in non-Hispanic whites, 31.3% in blacks, and 37.5% in Hispanics. In the fully adjusted multivariate model with white ethnicity as reference, the odds ratio of vitamin-mineral supplements use for blacks was 0.37 (95% CI 0.21 to 0.65) and for Hispanics was 0.56 (95% CI 0.30 to 1.03). In bivariate analyses, female gender, black ethnicity, being born in the US, and having coronary artery disease were significantly associated with herbal use (p < 0.05); however, in the fully adjusted multivariate model, only the female gender remained significantly associated with herbal use (OR 2.14; 95% CI 1.00 to 4.59). CONCLUSIONS: Use of herbs or vitamin-mineral supplements is common in very old people and varies by ethnicity.