Cost-utility analysis of robotic arm-assisted medial compartment knee arthroplasty

Aims

To perform an incremental cost-utility analysis and assess the impact of differential costs and case volume on the cost-effectiveness of robotic arm-assisted unicompartmental knee arthroplasty (rUKA) compared to manual (mUKA).

Methods

This was a five-year follow-up study of patients who were randomized to rUKA (n = 64) or mUKA (n = 65). Patients completed the EuroQol five-dimension questionnaire (EQ-5D) preoperatively, and at three months and one, two, and five years postoperatively, which was used to calculate quality-adjusted life years (QALYs) gained. Costs for the primary and additional surgery and healthcare costs were calculated.

Results

rUKA was associated with a relative 0.012 QALY gain at five years, which was associated with an incremental cost per QALY of £13,078 for a unit undertaking 400 cases per year. A cost per QALY of less than £20,000 was achieved when ≥ 300 cases were performed per year. However, on removal of the cost for a revision for presumed infection (mUKA group, n = 1) the cost per QALY was greater than £38,000, which was in part due to the increased intraoperative consumable costs associated with rUKA (£626 per patient). When the absolute cost difference (operative and revision costs) was less than £240, a cost per QALY of less than £20,000 was achieved. On removing the cost of the revision for infection, rUKA was cost-neutral when more than 900 cases per year were undertaken and when the consumable costs were zero.

Conclusion

rUKA was a cost-effective intervention with an incremental cost per QALY of £13,078 at five years, however when removing the revision for presumed infection, which was arguably a random event, this was no longer the case. The absolute cost difference had to be less than £240 to be cost-effective, which could be achieved by reducing the perioperative costs of rUKA or if there were increased revision costs associated with mUKA with longer follow-up.

Cost-utility analysis of total knee arthroplasty using 10-year data from a randomised controlled trial: Implant design influences quality-adjusted life year gain

BACKGROUND

The aim of this study was to perform a cost-utility analysis for total knee arthroplasty (TKA) over a 10-year follow up period.

METHODS

Two-hundred and twelve patients were randomised to receive either a Kinemax or a Triathlon TKA. Patients were assessed pre-operatively, and at 6 months, and 1, 3, 7 and 10 years postoperatively. The costs of the primary and revision surgery were accounted for. One-year quality-adjusted life year (QALY) gain was used to estimate 10-year gains using the established annual health gain discounts.

RESULTS

Forty-eight patients died and eight were revised during the follow up period. Overall QALY gain per patient over the 10-year period was 2.594 and the cost per patient was £6559, which resulted in a cost per QALY of £2761 at 10 years. The Triathlon group had a significantly greater QALY gain compared with the Kinemax (mean difference (MD) 0.53, 95% CI 0.03-1.03, P = 0.02), which resulted in a cost per QALY for the Triathlon group of £2521 compared with £3107 for the Kinemax group at 10 years. The 5% annual discount resulted in a significantly lower QALY gain (MD 0.135, 95% CI 0.201-0.354, P = 0.002), whereas the 3.5% annual discount resulted in non-significant difference in QALY gain compared with the actual gain (MD 0.021, 95% CI -0.084 to 0.077, P = 0.292).

CONCLUSIONS

TKA was a cost-effective intervention, and the Triathlon was associated with a greater cost effectiveness at 10 years. The 3.5% annual discounts for QALY gain would seem to be the most accurate, with an underestimation being observed with the 5% discount.

Hughes abdominal closure versus standard mass closure to reduce incisional hernias following surgery for colorectal cancer: the HART RCT

BACKGROUND

Incisional hernias can cause chronic pain and complications and affect quality of life. Surgical repair requires health-care resources and has a significant associated failure rate. A prospective, multicentre, single-blinded randomised controlled trial was conducted to investigate the clinical effectiveness and cost-effectiveness of the Hughes abdominal closure method compared with standard mass closure following surgery for colorectal cancer. The study randomised, in a 1 : 1 ratio, 802 adult patients (aged ≥ 18 years) undergoing surgical resection for colorectal cancer from 28 surgical departments in UK centres.

INTERVENTION

Hughes abdominal closure or standard mass closure.

MAIN OUTCOME MEASURES

The primary outcome was the incidence of incisional hernias at 1 year, as assessed by clinical examination. Within-trial cost-effectiveness and cost-utility analyses over 1 year were conducted from an NHS and a social care perspective. A key secondary outcome was quality of life, and other outcomes included the incidence of incisional hernias as detected by computed tomography scanning.

RESULTS

The incidence of incisional hernia at 1-year clinical examination was 50 (14.8%) in the Hughes abdominal closure arm compared with 57 (17.1%) in the standard mass closure arm (odds ratio 0.84, 95% confidence interval 0.55 to 1.27; p = 0.4). In year 2, the incidence of incisional hernia was 78 (28.7%) in the Hughes abdominal closure arm compared with 84 (31.8%) in the standard mass closure arm (odds ratio 0.86, 95% confidence interval 0.59 to 1.25; p = 0.43). Computed tomography scanning identified a total of 301 incisional hernias across both arms, compared with 100 identified by clinical examination at the 1-year follow-up. Computed tomography scanning missed 16 incisional hernias that were picked up by clinical examination. Hughes abdominal closure was found to be less cost-effective than standard mass closure. The mean incremental cost for patients undergoing Hughes abdominal closure was £616.45 (95% confidence interval -£699.56 to £1932.47; p = 0.3580). Quality of life did not differ significantly between the study arms at any time point.

LIMITATIONS

As this was a pragmatic trial, the control arm allowed surgeon discretion in the approach to standard mass closure, introducing variability in the techniques and equipment used. Intraoperative randomisation may result in a loss of equipoise for some surgeons. Follow-up was limited to 2 years, which may not have been enough time to see a difference in the primary outcome.

CONCLUSIONS

Hughes abdominal closure did not significantly reduce the incidence of incisional hernias detected by clinical examination and was less cost-effective at 1 year than standard mass closure in colorectal cancer patients. Computed tomography scanning may be more effective at identifying incisional hernias than clinical examination, but the clinical benefit of this needs further research.

FUTURE WORK

An extended follow-up using routinely collected NHS data sets aims to report on incisional hernia rates at 2-5 years post surgery to investigate any potential mortality benefit of the closure methods. Furthermore, the proportion of incisional hernias identified by a computed tomography scan (at 1 and 2 years post surgery), but not during clinical examination (occult hernias), proceeding to surgical repair within 3-5 years after the initial operation will be explored.

TRIAL REGISTRATION

This trial is registered as ISRCTN25616490.

FUNDING

This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 34. See the NIHR Journals Library website for further project information.

Burden of Pertussis in Individuals with a Diagnosis of Asthma: A Retrospective Database Study in England

Purpose

The impact of pertussis in individuals with asthma is not fully understood. We estimated the incidence, health care resource utilization (HCRU), and direct medical costs (DMC) of pertussis in patients with asthma.

Patients and Methods

In this retrospective cohort study, the incidence rate of pertussis (identified using diagnostic codes) among individuals aged ≥50 years with an asthma diagnosis was assessed during 2009–2018 using Clinical Practice Research Datalink and Hospital Episode Statistics databases. HCRU and DMC were compared – between patients with diagnoses of asthma and pertussis (asthma+/pertussis+) and propensity score-matched patients with a diagnosis of asthma without pertussis (asthma+/pertussis–) – in the months around the pertussis diagnosis (–6 to +11).

Results

Among 687,105 individuals, 346 had a reported pertussis event (incidence rate: 9.6/100,000 person-years of follow-up; 95% confidence interval: 8.6–10.7). HCRU and DMC were assessed among 314 asthma+/pertussis+ patients and 1256 matched asthma+/pertussis– controls. Baseline HCRU was similar in both cohorts, but increases were observed in the asthma+/pertussis+ cohort from –6 to –1 month before to 2–5 months after diagnosis. Rates of accident and emergency visits, general practitioner (GP)/nurse visits, and GP prescriptions were 4.3-, 3.1-, and 1.3-fold, respectively, in the asthma+/pertussis+ vs asthma+/pertussis– cohorts during the month before diagnosis; GP/nurse visit rates were 2.0- and 1.2-fold during 0–2 and 2–5 months after diagnosis, respectively (all p<0.001). DMC was 1.9- and 1.6-fold during the month before and 2 months from diagnosis, respectively, in the asthma+/pertussis+ vs asthma+/pertussis– cohorts (both p<0.001). During months –1 to +11, DMC in the asthma+/pertussis+ cohort was £370 higher than in the asthma+/pertussis– controls.

Conclusion

A pertussis diagnosis among adults aged ≥50 years with asthma resulted in significant increases in HCRU and DMC across several months around diagnosis, suggesting lengthy diagnosis times and highlighting the need for prevention strategies.

Burden of Pertussis in COPD: A Retrospective Database Study in England

Chronic obstructive pulmonary disease (COPD) may increase the risk and severity of pertussis infection. Health care resource utilization (HCRU) and direct medical costs (DMC) of treating pertussis among patients with COPD are unknown. Reported incidence of pertussis among individuals aged ≥ 50 years with COPD was assessed in Clinical Practice Research Datalink and Hospital Episode Statistics databases during 2009-2018 using a retrospective cohort design. HCRU and DMC from the National Health Service perspective were compared between patients with COPD and pertussis and propensity score-matched patients with COPD without pertussis. Seventy-eight new pertussis events were identified among 387 086 patients with COPD aged ≥ 50 years (incidence rate: 4.73; 95% confidence interval 3.74-5.91 per 100 000 person-years). HCRU and DMC were assessed among 67 patients with COPD and pertussis and 267 matched controls. During the month before the pertussis diagnosis, the rates of general practitioner (GP)/nurse visits (4289 vs. 1774 per 100 patient-years) and accident and emergency visits (182 vs. 18 per 100 patient-years) were higher in the pertussis cohort; GP/nurse visits (2935 vs. 1705 per 100 patient-years) were also higher during the following 2 months (all p < 0.001). During the month before the pertussis diagnosis, annualized per-patient total DMC were £2012 higher in the pertussis cohort (£3729 vs. £1717; p < 0.001); during the following 2 months, they were £2407 higher (£5498 vs. £3091; p < 0.001). In conclusion, a pertussis episode among individuals with COPD resulted in significant increases in HCRU and DMC around the pertussis event.