Characteristics and Outcomes of Older Adults Following Distal Forearm Fracture

Abstract

Introduction Osteoporosis and fragility fractures pose a serious public health challenge in our ageing society. Systems are being developed in Ireland and internationally to provide, coordinated and comprehensive assessments and multidisciplinary, evidence-based interventions in patients presenting with fragility fractures. An evidence gap exists regarding both patient outcomes and their predictors following these fractures. Distal forearm fracture (DFF) includes fracture of the distal radius and/or ulna and is one of the most common fragility fracture sites. Vertebral fractures also comprise a large proportion of fragility fractures. Understanding the characteristics of these patients can help in planning and developing appropriate systems of care. Exploring factors that affect patient outcomes will enhance the current evidence base and may help in the development of more targeted pathways to improve clinical outcomes.

Aims (a) To examine in detail the characteristics of patients with distal forearm fracture who attended the Bone Health Unit at St James's Hospital. (b) To examine in detail the characteristics of patients with (1) vertebral fracture(s) and (2) both vertebral and distal forearm fracture(s) attending the above unit. (c) To prospectively investigate the characteristics of patients following a low trauma distal forearm fracture presenting to St James's Hospital. (d) To assess outcomes (clinical and other) in the above prospective cohort and study the factors related to these outcomes.

Methods This thesis included three interlinked studies. Study one (discussed in chapter 2) was a cross-sectional study of patient characteristics with a history of distal forearm fracture (DFF) on their first presentation to the bone health clinic. Study two (discussed in chapter 3) was also cross-sectional and looked at patients with a history of vertebral fracture (VF) on their first presentation to the same clinic. Data was collated regarding demographics, medical history, biophysical measures and bone health assessments (DXA, QUS heel, bone turnover markers- BTM) and relationships were explored. Similarities and differences between those with DFF and VF or both fractures were examined.

Study three (discussed in chapters 4, 5 and 6) is a prospective cohort study of all patients presenting to St James's Hospital, Dublin with DFF between January and October 2018 and assessed participants soon after their fracture and again at six and twelve months. The first visit included a 90 minute in person assessment of falls and bone health, as well as recording of medical history, Charlson Comorbidity Index (CCI), dietary calcium intake, and assessment of Mini Mental State Examination (MMSE), frailty and biophysical measures (weight, height, timed up and go (TUG), grip strength, lying and standing blood pressure, DXA, QUS heel, bone turnover markers (BTM's) and other blood tests). Patient reported outcomes measures (PROMS) were assessed using standardized measures including the Patient Rated Wrist Evaluation (PRWE), Disability of the Arm, Shoulder and Hand (DASH) and the Short Form 12 (SF12) at all three visits. Other outcomes were recorded including time not working or driving, falls and fracture, need for initial or future hospital admission, medication adherence and changes in other factors related to bone health (exercise, dietary calcium, vitamin D and BTMs). Non-attendance and death were also recorded.

Results In the first two studies, we identified a total of 1724 patients with DFF and 1779 with VF, of whom 426 had both fractures. Most patients were female and this was more likely in those with DFF versus VF (86.3% vs 73.1% P=0.000). Those with DFF vs VF were younger (66.3 vs 71.5 years, P=0.000) and had a lower rate of polypharmacy (33.5% vs 47.8%, P=0.000). Prevalence of densitometric osteoporosis varied and was 56.4% with DFF only, 57.2% VF only and 62.6% with both fractures. Only 10% with a single fracture had normal BMD and only 5% with both fractures. Patients with lower BMD were more likely be older, female and have lower BMI. We also noted that 48.3% of DFF patients with a normal DXA had an QUS calculated T score below -1.0. More than half of the patients with both fractures were not taking anti-osteoporosis medication highlighting a significant 'treatment gap'.

In the prospective cohort study, there were 133 patients, and data were available for 87% (n=116) at one year follow up. At baseline, 93.2% were female and mean age was 69.3 years. Almost one in five had a CCI > 4 and 25% were frail. Over a third had polypharmacy and 40% had densitometric osteoporosis with only 10% having normal BMD. DXA forearm identified a further 15% (74/132) with BMD in the osteoporotic range. Factors associated with a diagnosis of osteoporosis included frailty, low BMI, low dietary calcium intake and reduced grip strength. Almost half (45.9%) had a history of previous fracture and 39.8% reported early menopause (< 45 years). About one quarter reported ? 2 falls in the previous year and the same proportion had orthostatic hypotension. Two thirds (67.7%) of patients were started on a new antiresorptive medication while 9% continued their current osteoporosis therapy. There were significant improvements at year in exercise levels (21.1% reported doing more), dietary calcium intake (increased by 14.2%) and bone turnover markers (reduction of CTX by 54.2%).

Two patients were in hospital at the time of their DFF, though a further 33 (24.8%) were admitted for surgery for their fracture. Excluding these patients, an additional 18 required admission for ? 2 days and their median length of stay was 48 days. These patients were older, had higher rates of polypharmacy, multimorbidity, frailty, cognitive impairment and functional dependence. They were also more likely to have sustained another injury at presentation, and have a history of vertebral fracture(s) and lower BMD. Despite this, only four of these patients were discharged to long-term care and a further seven required significant home supports. There were four incident fractures and four deaths in the year after DFF. However, 26 (19.5%) required subsequent hospitalisation and these patients were more likely to be frail, anaemic and have multimorbidity

I identified a significant improvement in PROMs in the first year following DFF, especially in the first six months. Half of the participants (56 /111) were pain free at 12 months as reported on PRWE. However, only 5 (5.4%) had no disability at one year (as reported on DASH). Factors associated with poorer outcomes included dominant hand fracture, older age, female sex, frailty, polypharmacy, lower BMD, previous fracture, and hospital admission at the time of the fracture.

Discussion This is the largest study in Ireland to characterize patients with DFF and the only one to prospectively follow up and assess outcomes over a one-year period post fracture. Results highlight the high prevalence of low bone mass and osteoporosis in patients with fragility fractures of the wrist and spine. Between 12.8-24.0% of patients with DFF had a history of vertebral fracture. The role of DXA with vertebral fracture assessment (VFA) to appropriately evaluate these patients as well as the need for specialist services and anabolic therapy needs to be considered. An important finding were the low rates of prior and current treatment with anti-osteoporosis medication (12.8% in study 3, 37.5% in study 1 and 44.4 % in study 2), This highlights a ?treatment gap? between those eligible for and actually on treatment, and the need for robust FLS, fracture/falls risk assessment and interventions at or soon after fracture presentation. Indeed, the rate of incident fracture in this study was low at (3%) but this might be in part accounted for by the high proportion started on anti-osteoporosis medication and good compliance with therapy.

A research gap in older adult trauma is the lack of evidence regarding patient outcomes following fragility fractures. I found significant improvement in patient reported outcomes, especially over the first six months post DFF. Factors associated with poorer outcomes included some that were previously reported, However, I also identified other factors correlated with poorer outcomes that have not been examined before, including frailty and recurrent falls. This study is also one of the largest to explore the association between BMD and DFF outcomes and found a significant positive relationship.

As regards health care usage in patients with DFF, I identified that 18/98 (18.4%) not requiring surgery, were admitted to hospital for more than 2 days, at the time of the fracture presentation. However, half had a inpatient length of stay more than 48 days accounting for a total of 1024 bed days and costing an estimated ?899,072. Given that these patient were older, physically frailer and cognitively impaired, there may be a role for early geriatrician led multidisciplinary care to optimise their outcomes and facilitate earlier discharge.

Importantly, resulting from my studies the number of fractures identified by the FLS in St James's Hospital was significantly increased as all DFF were captured from x-ray reports as opposed to only patients admitted and recorded on the Hospital In-Patient Enquiry (HIPE) system. I identified a high rate (34.6%) of cancellation and non-attendance for appointments with patients attending after versus within 12 weeks of fracture being more likely to be frail and functionally dependent. The IOF Best practice frameworks for FLS recommend evaluation within 8 weeks for level 3 performance and 12 weeks for level 2 performance, so this has important implications for service planning. In such patients, consideration should be given for telephone or virtual clinics.

Conclusion Study findings show there is a high prevalence of densitometric low bone mass/osteoporosis in Irish adults with DFF. Furthermore, a high proportion had a history of other fragility fractures though despite this, there was a significant treatment gap. In fact, up to nearly 80% in my cohort study were deemed to need anti-osteoporosis therapy. This highlights the importance of further expansion of FLS throughout Ireland. As a quarter of patients with DFF had recurrent falls and orthostatic hypotension, it should be incorporated into falls risk assessment. Compliance with osteoporosis therapy for patients with DFF was good, likely reflecting the value of follow up appointments and patient education. 18.4% of patients with DFF were admitted to hospital despite not needing surgical correction of their fracture contributing to a significant number of bed days. These patients were older and frailer, and these factors were also associated with poorer outcomes at one year. For this reason, they are likely to benefit from orthogeriatric care which should be expanded beyond hip fractures patients. This could positively impact clinical outcomes but also might reduce patient length of stay. The recently initiated FLS audit of several pilot hospital sites in Ireland will be important in establishing deficits in key performance indices with regard to fragility fractures and the need for improvements in care.