A prospective cohort study measuring cost-benefit analysis of the Otago Exercise Programme in community dwelling adults with rheumatoid arthritis

Rheumatoid arthritis (RA) is an inflammatory disease of unknown cause that first targets synovial tissues, cartilage and bone. It is the most common form of immune-mediated arthritis affecting approximately 1% of the adult UK population [1, 2], with a global prevalence of 0.24% [3]. Symptomatic patients with RA present with joint pain, swelling, muscle weakening with fatigue and reduced functioning [4–8]. In the community, falling is a problem especially among adults aged 65 years or older, for whom falls are the main cause of both fatal and non-fatal injuries [9]. It is estimated that 30–35% of people in the community aged 65 and above have at least one fall per year [10, 11]. In adults with RA the risk of falling is even greater, with the annual incidence rate estimated to be between 10 and 54% [4–7, 12–18] and in contrast to those without RA the risk appears to be broadly similar across the age bands [19].

Most of the injuries resulting from a fall are non-fatal (e.g. bumps and bruises), but approximately 10–25% of falls result in more serious injuries such as hip fractures, head trauma or internal bleeding [9, 20]. Falls can affect a person’s morbidity and quality of life and also impact the health care system in terms of medical costs [9, 21, 22]. Falls are a common cause of Emergency Department visits, acute care admissions and hospitalisation among adults aged 65 years and over [22–24]. Apart from the acute care costs to consider there are also the social care costs which, according to estimates from the UK Department of Health’s economic evaluation, will incur ongoing costs of £1872(US$2702) per fracture patient, per year [25].

Many of the risk factors for falls, such as poor balance and gait or mobility impairments, can be improved by exercise [9]. Implementing effective prevention strategies could therefore potentially reduce the risk of falling, decrease the incidence of falls and reduce associated health care costs [26]. There is abundant evidence that exercise programmes that improve balance muscle strength and walking ability are effective in preventing falls [27–30]. Clinical trials provide evidence that an exercise programme as a single intervention can prevent falls in older adults living in the community [30–32].

The Otago Exercise Programme (OEP) is considered for implementation in patients with RA because it has demonstrated to be one of the most beneficial programmes to prevent falls [30, 33]. The programme consists of individually tailored muscle strengthening and balance retraining exercises with increasing difficulty combined with a gait-improving programme. The aims of the programme are to improve patient’s strength and balance and increase their confidence in carrying out everyday activities without falling. The programme has the greatest impact among high-risk groups; such as those with a previous fall and those aged 80 and above [31]. In the four trials studied with 1016 people ages 65 years to 95 years in nine cities and towns in New Zealand, the OEP reduced the rate of both falls and fall related injuries by 35% [30, 33]. A more recent systemic review and meta-analysis (88 trials with 19,478 participants) showed similar strong evidence that exercise that challenged balance and involved more than 3 h/week of exercise led to a 39% reduction in falls [32].

Trained physiotherapists or nurses are able to deliver the programme in the home setting. Patients are shown how to do a set of in-home exercises tailored to their needs during a one-hour visit and 3 to 4 half hour visits over the first 2 months. The exercises take approximately 30 min to complete. They are encouraged to walk outside twice a week and to complete the exercises three times a week. The aim of implementing this programme is to improve health and wellbeing of people by preventing falls and fall related injuries and reducing the impact on the healthcare services. The proposed net financial benefit would be that the averted healthcare costs outweigh the cost of implementing the programme. Such financial information would be beneficial in determining whether investing in the OEP as an intervention to prevent falls would provide a positive return of investment (PRI) for the National Health Service (NHS) or other such health providers.

To date there are no studies which have looked at interventions to reduce the risk of falls in adults with RA. Assuming similar benefits of the OEP programme as those without RA we looked at the potential cost savings if such a program were implemented. We used prospective follow up data on falls and determined the costs associated with falls in men and women with RA.

This study shows a high economic benefit of the OEP when delivered to community dwelling adults aged 18 years and older; it estimated a yielded ROI of more than 100%. The yielded return is obtained by comparison with the healthcare costs of £1120 (US$1617) per fall, for which the costs was obtained from the financial year 2013/2014. This value is based on the assumption that after an injury the individual used certain health services, for instance if they had a fractured hip it is assumed that they received hip surgery.

There is no literature on the direct cost of falls in patients with RA. In this study the estimated average healthcare cost per fall in patient with RA is £1120 (US$1617). In countries such as Finland and Australia the average healthcare cost per fall for people 65 and above is between £724–£2492 (US$1049–$3611), and this is regardless to whether the fall required hospitalisation [24].

In our study the OEP cost £217.72 or $314.34 (US Dollars) per person. Other studies in the US have estimated this cost at $339 (£233) [39]. The average intervention cost is highly influenced by staff salary costs and the format of the programme, this and the use of marketing in the US may have resulted in the 7% difference. In the NHS marketing cost is not expected as it is assumed that current health care trusts can roll out the programme using existing staff that can be trained.

This study has several limitations. The data on fall occurrence was based on self report and subject therefore to errors of recall, and so our data may underestimate the occurrence of falls in this group. Efforts made to reduce the likelihood of underreporting include the provision of prepaid preaddressed daily calendar postcards to be returned on a monthly basis with follow up calls for non-responders. The effect of any underreporting, however, would be to underestimate the economic burden of the falls. Falls that were reported using the calendars were verified by telephone calls and followed up to gather more information about the type of fall and any injuries. This information was used to categorise the fall according to severity by using both type of injury (fractures, internal bleeding and sprains) and healthcare service utilisation (e.g., hospital admission, stitches, and physiotherapy). Again, however, the data was based on self report and subject therefore to errors of recall. A randomised controlled trial would exclude these errors and give more control over the study. The healthcare costs for a fall was calculated using maximum information accessible, however it is still based on the assumption that certain services was provided which may not have been the case. Additionally the costs-benefit analysis in favour of implementing the OEP holds strictly to the assumptions used for estimating the average cost of the intervention.

We have performed a sensitivity analysis based on removing the costs that we assume, and are not based on the self-reported data. This involved subtracting 14% (the assumed cost; Fig. 2) from the total sum. This gives a total cost sum of £321,944 and hence a net-benefit of £88,8986. However, as we believe the assumptions that we make are realistic, we prefer the main discussion to focus on the full results. It would be highly unlikely for participants who have had serious falls not to have received treatment especially so if they had an overnight stay in the hospital.

The data in this study suggest that management of RA patient should, because of the cost savings, include a fall prevention programme such as the OEP. Given the higher risk of falls among those who have already experienced a fall, it might be offered in the first instance to those with a fall in the previous year. In this study only the OEP has been used and this has not been compared with other exercise programmes. Further research should include a cost-benefit comparison between OEP and other exercise programmes (as well as estimating the costs and efforts involved in undertaking the OEP in a RA specific population). There are other interventions that can be delivered at home by health professionals to maximise effectiveness and reduce falls. These include, assessments and modifications of environmental hazards [40], home safety advice and referral to doctors for re-assessment of psychotropic drugs [41]. The intervention has demonstrated to reduce falls by 35% and reduce moderate and serious injuries by 40%; this can reduce healthcare service utilisation and in turn reduce healthcare costs [41].

The implementation of the programme for patients with RA has potentially significant economic benefits and should be considered as part of an overall management strategy for patients with the disease. To further investigate and reinforce the findings of this study a randomised controlled trial should be conducted.