Commentary

Previous studies have shown the beneficial effects of exercise for older adults,^1–,³ but no consensus exists on the appropriate quantity, quality, or intensity of exercise necessary to promote improved health and function in this population. Hence, it is difficult to know what would work best for frail older adults. Latham et al and Schnelle et al explore the transferability of what has been learnt in clinical research into the delivery of efficient and cost effective interventions in 2 groups of frail older adults.

The goal of the study by Latham et al was to identify an intervention that could be easily and inexpensively incorporated into existing home healthcare services. To decrease the complexity and improve the feasibility of the intervention, Latham et al selected 1 component of a multifaceted exercise programme and a 1 time dose of vitamin D for testing. However, neither simple quadriceps training nor vitamin D supplementation alone was sufficient to prevent falls in older adults who had recently been admitted to hospital.

The purpose of the study by Schnelle et al was to determine if reducing the incidence of costly health conditions could offset additional staffing requirements needed to implement the intervention. However, the study was powered for a 16% improvement in outcomes, rather than the more modest 10% improvement achieved in the study. According to Schnelle et al and others,⁴ direct comparison of costs without weighting improvements in functionality and other desired outcomes may not be the best approach to determine if an intervention is worth the extra cost.

The results of these studies are relevant to nurses who work in long term care and community settings with frail older adults. The findings increase our knowledge of factors that affect the translation of clinical research into everyday practice. Firstly, the intervention dose must be carefully considered; single strategies may not be effective for individuals with complex problems and needs. As Latham et al noted, an exercise programme using more muscle groups or performed for a longer duration may have been more effective, and other studies have shown the effectiveness of more complex exercise regimens, albeit not typically on such a frail population.⁵ The vitamin D supplementation dose was not sufficient to correct elevated parathyroid hormone concentrations that may be responsible for compromising muscle strength.⁵ Both calcium and vitamin D in sufficient quantities may be required to achieve the improvement sought.⁵

Secondly, cost of the intervention may not be the most appropriate criterion for adoption into practice. Although it was hoped that the benefits might be gained at no extra cost, this is rarely achieved in health care. Decisions about resource allocation should be made on the basis of information about costs and benefits. The exercise and incontinence intervention tested in the NH clinical trial⁶ on which the economic analysis was based resulted in improvement or prevented decline in mobility, upper body strength, and continence in most of the intervention group patients. However, Schnelle et al found that the staffing requirements needed to implement the intervention (1 aide to 5 patients) exceeded the staff resources available in most (92%) NHs and were not offset by reductions in other costly care. Staffing limitations may therefore prevent the successful transfer of this and similar exercise and incontinence interventions to NH clinical practice. The data reported in this study provide evidence that nurses’ aide staffing ratios advocated in recent government studies and by consumer groups⁷ as necessary to provide high quality NH care are justified.