74 Use and Cost of Hospital Services by UK Biobank Participants with Potentially Serious Incidental Findings

Background Feedback about potentially serious incidental findings (PSIFs) on research imaging leads to clinical assessment in almost all cases. Previous studies have been small, or focused on patients, or non-UK settings. We used a novel four-way comparison to assess the economic impact on UK hospital services of feeding back PSIFs to research volunteers within the UK Biobank Imaging Study. Methods We matched (by age, sex, imaging date and prior morbidity [Elixhauser index]) 179 cases, who received feedback about a PSIF identified following either magnetic resonance imaging or dual-energy X-ray absorptiometry, to controls without a PSIF. We calculated the hospital costs of cases and controls by applying National Reference Costs to linked Hospital Episode Statistics inpatient, outpatient, accident and emergency and critical care datasets from 2013–2016. We conducted four-way comparisons of data from cases and controls during the year before and after feedback of a PSIF (cases before versus after, controls before versus after, cases versus controls before and after). We compared mean differences in hospital contacts and costs (with 95% confidence intervals [CI] calculated using bootstrapping techniques) and differences in proportions with ≥ 1 hospital contact using McNemar’s tests between groups, and calculated cumulative costs. We performed sensitivity analyses using only those case-control pairs with no prior morbidity. Results There were no differences in mean numbers of hospital contacts or costs between cases and controls before feedback, or between controls before and after feedback of a PSIF. Following feedback, 144 (80.5%) cases, and 94 (52.5%) controls used hospital services. Mean numbers of hospital contacts and mean costs were higher in cases compared to controls after feedback, and compared to cases before feedback (hospital contacts: 5.4 [standard deviation 6.2] versus 3.2 [5.7] and versus 2.7 [4.7]; costs: £2,409 [£4,781] versus £935 [£2,439] and versus £826 [£2,179]). Cases’ cumulative costs began to increase approximately 30–60 days following feedback of a PSIF. A year after feedback of a PSIF, total hospital costs for cases (£431,114) were almost three times higher than for controls (£147,817) and for cases the year before (£167,434). Compared to the year before, after feedback of a PSIF total costs had increased 10 times in serious cases, and two times in non-serious cases. Most PSIFs were non-serious (158/179 [88%]). Although serious cases generated higher mean costs after feedback than non-serious cases (£9,147 [£10,234] versus £1,513 [£2,386]), the 7.5-fold greater number of non-serious cases generated higher total absolute costs than serious cases (£239,021 versus £192,093). These patterns of costs persisted over longer follow-up, and in sensitivity analyses. After feedback of a PSIF, most costs related to inpatient services (68.3%). Conclusions After feedback of a PSIF, research volunteers used substantially more hospital services compared with controls or with the year before. Total cost and service impacts were higher among cases with non-serious, rather than serious final diagnoses, as most PSIFs represented non-serious disease. Avoidance of unnecessary feedback through ensuring non-serious PSIFs feedback policies are appropriate to the research setting would enable researchers and policymakers to minimise unwarranted impacts on publicly-funded healthcare services.