Discussion
A variety of clinical trials of exercise as a single intervention for falls prevention in community-dwelling older people have been published. There are clear implications for practice and research. Descriptions of the characteristics of exercise programmes that contributed to effective intervention types may guide clinicians in developing optimal programmes for their patients. Identification of gaps and methodological flaws in fall prevention studies will guide future research.
In summary, most trials took place in developed countries, involved a wide age range and predominantly comprised female participants. Most trial populations had higher risk of falls, indicated by history of falls, poor balance, recent hospitalisation or poor mobility as inclusion criteria. Adherence to exercise was suboptimal. Balance and functional exercises were the most common primary intervention and had the greatest effect on falls. The duration and hours of intervention varied. While most interventions were group based and tailored to the individuals, the level of supervision was not clearly reported. Furthermore, the majority of trials did not clearly report allocation concealment and blinding of participants and personnel.
Implications for practice
Within the effective interventions, involving balance and functional exercises, Tai Chi and multiple types of exercise (typically incorporating balance and strength exercises), there are different ways the interventions can be delivered. Clinicians and exercise programme providers need to note the characteristics of trials that contributed to fall prevention effects, and work with patients to establish the most suitable exercise programme for the individual.126
The updated Cochrane Review8 is consistent with previous systematic reviews6 7 127 that identified greater falls prevention effects from exercise programmes that challenge balance. This element was present in all the effective interventions: balance and functional training, Tai Chi and multiple types of exercise. Challenge to balance can be achieved by progressively reducing the base of support, removing upper limb support and moving the centre of gravity to challenge balance. Strength training alone did not prevent falls, however when included in a programme with balance training, a fall prevention effect was evident. This is consistent with previous research that recommend exercise programmes targeting falls may include strength training in addition to balance training.6 127
For exercise to be effective a sufficient intensity and duration of exercise is required. In the trials with interventions classified primarily as balance and functional training, the median intervention duration was 6 months, with a total of 52 hours (approximately 2 hours per week). In trials with interventions classified primarily as Tai Chi, the median duration was 4 months, with a total of 45 hours (approximately 2.8 hours per week). For trials with interventions that included multiple primary components, the median intervention duration was 6 months, with a total of 54 hours. This is less than the 3 hours of exercises per week recommended for falls prevention, following a previous systematic review with meta-regression.6 In addition, ongoing exercise is needed to maintain the falls prevention benefit of exercise.6 The trial nature of these programmes limited their duration and clinicians need to discuss strategies with their patients to keep them exercising in the long term.
The Cochrane Review found there may be no difference in the effect of exercise on the rate of falls where interventions were delivered in a group setting compared with trials where interventions were delivered individually.8 In the effective intervention types, home-based interventions were frequently delivered as, or based on, the Otago Exercise Program. Home-based interventions, or group-based interventions with less than 10 participants, were mostly tailored in type or progression. For home-based programmes, the instructor usually makes an initial home visit to the participant’s residence to individually tailor the programme, with follow-up sessions for assessment and progression. For the group-based intervention, an instructor may adjust the individual’s tasks within a predefined programme. On the other hand, most group interventions with more than 10 participants per instructor were not tailored to individuals. Clinicians need to balance the increased social support and adherence from supervised group-based intervention with the sustainable self-motivation for exercise from individualised home-based intervention.128 129 Interventions combining both delivery modes have the potential to provide the benefit from both sides.
Optimising adherence is another important consideration during design and implementation of an intervention programme.130 Given the suboptimal level of compliance, clinicians should therefore incorporate effective strategies to promote adherence such as involving the patients in shared decision-making, goal setting and framing the interventions as life enhancing.128 130
There is sufficient evidence available to support the use of exercise to prevent falls, providing clinicians an opportunity to implement evidence-based shared decision-making. Evidence-based medicine requires clinicians to integrate the evidence with patient preferences.131 A decision aid could be developed to help clinicians and patients aware of the options and programmes available to them in the area.132
Implications for research
Several areas of deficiency in the arena of falls prevention research were identified in this review. There is a lack of clinical trials investigating the effect of exercise in preventing falls from the African continent and China, areas that represent a significant proportion of older adults in the world and are ageing rapidly.133 Low and middle-income countries and low-income countries are also under-represented, presenting a barrier in translating cost-effective exercise interventions to clinicians in these countries.12 Furthermore, exercise intervention trials that specifically target males are lacking with only one trial available. While the risk and incidence of falls are greater in females, the mortality rate due to falls is higher for males, suggesting more clinical trials for men are needed in preventing particular circumstances of falls.134 There was insufficient research evaluating programmes containing primarily flexibility and endurance exercise and little research evaluating only resistance training and only walking programmes. Finally, there is a need for cost-effectiveness analysis to investigate any economic benefit of home-based or individually tailored interventions for falls prevention.
Risk of bias and deviation of clinical trials from study design and reporting guidelines reduces their credibility. The reporting of a substantial number of trials did not meet the standards of the Consolidated Standards of Reporting Trials statement,135 for example, one-third omitted a sufficient description of randomisation and almost two-thirds did not describe allocation concealment. Due to the nature of exercise interventions, it is extremely difficult to blind the participants or personnel. This amplifies the need to minimise the risk of ascertainment bias (bias in the recall of falls due to unreliable methods of ascertainment); yet 42% did not satisfy the criteria for low risk. Falls are under-reported when data are collected on a three monthly basis, compared with daily.136 To minimise bias, the ascertainment of falls should follow the ProFaNE consensus137 of daily recording of falls using falls calendars and monthly follow-up analysis performed by researchers blind to participants’ allocation. Almost half of the studies did not report participant-to-instructor ratio; consistent reporting guidelines on the level of supervision should be promoted. Evidence-based medicine is the implementation of high-quality evidence in clinical practice13; however, if the presentation of the evidence is not of high quality, then it would impede the utilisation of the findings by clinicians. Therefore, quality study methodology and satisfaction of the reporting guidelines should be promoted.
This report has limitations. This review did not include trials specifically recruiting older adults with dementia, stroke, Parkinson’s disease, multiple sclerosis or hip fracture. While these conditions are associated with a higher risk of falls, the effect of exercise on falls in these populations has been covered previously138 139 and we aim to make the study results generalisable to the community-dwelling older people. Exercise as part of a multicomponent intervention was excluded from this review as this is covered elsewhere.9 Coding of intervention type was limited to the information available in the papers or provided by the authors, which may be inaccurate. Multiple databases were searched and studies published in language other than English were included in an effort to minimise publication bias. More research is needed for categories of interventions not found to prevent falls and readers should be cautious to interpret it as ‘no evidence of effect’ rather than ‘evidence of no effect’.
