Annals of Long Term Care

Introduction
Clinicians are often faced with concerns about adequate nutrition in older long-term care (LTC) residents. In the absence of demonstrated deficiency or clear risk, the benefit of supplementation may be debatable, but unquestionably, supplementation should not cause harm. This article addresses the supplementation of three vitamin groups: vitamin A, vitamin B complex, and vitamin D.

A vitamin deficiency is defined as “Hypovitaminosis accompanied by physiological or biochemical abnormalities.”1 Simply stated, supplementation should be used to treat or prevent the development of a deficiency. Before deciding to supplement with a vitamin, risk for deficiency and toxicity should be determined. Table I provides questions that should always be considered when contemplating vitamin supplementation.

Evaluation of risks and benefits should include cost of the supplement, administration, and monitoring for benefit and side effects. The treatment population also requires consideration. For example, vitamin A supplementation may be felt to be important for a portion of a younger population at risk for vision loss or susceptible to infection, but one could argue that such supplementation is not necessary or even appropriate for the bulk of nursing home residents. Depending on definition and measures, studies indicate that the prevalence of vitamin B₁₂ deficiency is between 5% and 40% for subjects over age 65 years.2 Vitamin B complex has been used even in the absence of demonstrated deficiency for cognition or cardiovascular health. There is some evidence for general supplementation in the LTC setting. Vitamin D may be recommended for skeletal effects, but data indicate that nonskeletal effects may be as important in the LTC environment. Where the following three criteria are met, it may be reasonable to supplement broadly in the LTC setting with targeted assessments as clinically indicated: (1) vitamin deficiency or risk of deficiency is high; (2) risk associated with supplementation is low; and (3) evaluation of vitamin status is costly.

Vitamin A
Vitamin A is fat-soluble and takes months to become depleted. Food supplements typically have amounts of vitamin A that often equate to one-quarter of the Recommended Dietary Allowance (RDA) or more. The current RDA for vitamin A is 5000 IU. Nutritional supplements typically have ample amounts of vitamin A (25% of the RDA in 8 oz portions of commonly used liquid preparations is typical; Table II). There are little data to indicate that vitamin A deficiency is a problem in adults in the United States. Even in homebound and nursing home residents followed with three-day food records, there was little evidence to support inadequate vitamin A intakes.3 The concept of vitamin A as being beneficial for infection also has not been substantiated based on a study in the LTC setting.4 Additionally, no good confirmed studies of benefit to vitamin A supplementation in the LTC setting have been published. In addition to a lack of evidence for vitamin A supplementation, there is actually potential for harm. Recent studies have looked at negative outcomes from vitamin A. Vitamin A was actually linked to reduced bone density and/or increased risk of fracture (Table II).5-7More recently, a review of antioxidant vitamins also showed an increased risk of mortality and morbidity with excessive intake of vitamin A and beta-carotene.8

Vitamin B Complex
Some recent studies have evaluated the prevalence of vitamin B complex deficiency. While vitamins B₁, B₂, B₃, and B₆ (thiamine, riboflavin, niacin, pyridoxine) are not commonly used in the nursing home setting unless they are part of a multivitamin preparation, vitamin B₁₂ and folate are more frequently provided in the LTC setting.