Diffusion of good practices of care and decline of the association with case volume: the example of breast conserving surgery

Volume-outcome relationship in transcatheter aortic valve implantations in Germany 2008-2014: a secondary data analysis of electronic health records

OBJECTIVES

We examine the volume-outcome relationship in isolated transcatheter aortic valve implantations (TAVI). Our interest was whether the volume-outcome relationship for TAVI exists on the centre level, whether it occurs equally for different outcomes and how it develops over time.

DESIGN

Secondary data analysis of electronic health records. The comprehensive German Federal Bureau of Statistics Diagnosis Related Groups database was queried for data on all isolated TAVI procedures performed in Germany between 2008 and 2014. Logistic and linear regression analyses were carried out. Risk adjustment was applied using a predefined set of patient characteristics to account for differences in the risk factor composition of the patient populations between centres and over time. Centres performing TAVI were stratified into groups performing <50, 50-99 and ≥100 procedures per year.

SETTING

Germany 2008-2014.

PARTICIPANTS

All patients undergoing isolated TAVI in the observation period.

INTERVENTIONS

None.

PRIMARY AND SECONDARY OUTCOME MEASURES

In-hospital mortality, bleeding, stroke, probability of ventilation >48 hours, length of hospital stay and reimbursement.

RESULTS

Between 2008 and 2014, a total of 43 996 TAVI procedures were performed in 113 different centres in Germany with a total of 2532 cases of in-hospital mortality. Risk-adjusted in-hospital mortality decreases over the years and is lower the higher the annual procedure volume at the centre is. The magnitude of the latter effect declines over the observation period. Our results indicate a ceiling effect in the volume-outcome relationship: the volume-outcome relationship is eminent in circumstances of relatively unfavourable outcomes. Alongside improving outcomes, however, the volume-outcome relationship decreases. Also, a volume-outcome relationship seems to be absent in circumstances of constantly low event rates.

CONCLUSIONS

The hypothesised volume-outcome relationship for TAVI exists but diminishes and may disappear over time. This should be taken into account when considering mandatory minimum thresholds.

For-profit hospital ownership status and use of brachytherapy after breast-conserving surgery

BACKGROUND

Little is known about the relationship between operative care for breast cancer at for-profit hospitals and subsequent use of adjuvant radiation therapy (RT). Among Medicare beneficiaries, we examined whether hospital ownership status is associated with the use of breast brachytherapy--a newer and more expensive modality--as well as overall RT.

METHODS

We conducted a retrospective study of female Medicare beneficiaries who received breast-conserving surgery for invasive breast cancer in 2008 and 2009. We assessed the relationship between hospital ownership and receipt of brachytherapy or overall RT by using hierarchical generalized linear models.

RESULTS

The sample consisted of 35,118 women, 8.0% of whom had breast-conserving operations at for-profit hospitals. Among patients who received RT, those who underwent operation at for-profit hospitals were more likely to receive brachytherapy (20.2%) than patients treated at not-for-profit hospitals (15.2%; odds ratio [OR] for for-profit versus not-for-profit: 1.50; 95% confidence interval [95% CI] 1.23-1.84; P < .001). Among women aged 66-79 years, there was no relationship between hospital ownership status and overall use of RT. Among women ages 80-94 years of age--the group least likely to benefit from RT due to shorter life expectancy--undergoing breast-conserving operations at a for-profit hospital was associated with greater overall use of RT (OR 1.22; 95% CI 1.03-1.45, P = .03) and brachytherapy use (OR 1.66; 95% CI 1.18-2.34, P = .003).

CONCLUSION

Operative care at for-profit hospitals was associated with increased use of the newer and more expensive RT modality, brachytherapy. Among the oldest women who are least likely to benefit from RT, operative care at a for-profit hospital was associated with greater overall use of RT, with this difference largely driven by the use of brachytherapy.

Measuring the influence of colleagues on a consultant team's use of breast conserving surgery

OBJECTIVES

The aim of this study was to examine potential reasons why the use of breast conserving surgery (BCS) for breast cancer varies substantially between hospital teams in England, and in particular to examine whether colleague influence has a role in influencing BCS rates locally.

METHODS

Routinely collected Hospital Episode Statistics (HES) data relating to 420 surgical teams in England who performed more than ten breast cancer operations during the financial year 2006/07 were used to identify predictors of team BCS use. Team BCS rates (as a proportion of all types of breast excision surgery) were subject to a regression analysis that incorporated, as independent variables, a range of patient, organizational, and local demographic factors, as well as the BCS rate of colleagues working alongside them in the same hospitals(s).

RESULTS

After adjusting for the effects of other variables, BCS use by colleagues working in the same hospital(s) was a significant predictor of a team's own BCS rate (standardized b = 0.224; p < .001), denoting a typical 3 percent increase in a team's BCS rate for every 10 percent increase in the BCS rate of colleagues.

CONCLUSIONS

The practice of colleagues seems to have a measurable influence upon a surgical team's BCS usage. Guidance from HTA organizations can set national standards about the use of new techniques and innovations, but dissemination can be either slowed down or accelerated by the influence of local colleagues. A strategy of disseminating guidance through professional networks or "local champions" could be a powerful avenue for change.

Does Center Volume Correlate with Survival from Breast Cancer?

With its high incidence and long history of patient advocacy, breast cancer has generated the most concern about the quality of its care and the volume-outcome relationship. In breast cancer surgery, the risk of perioperative morbidity or mortality is low, but surgery is only one single piece in the mosaic of multidisciplinary care that eventually determines survival. Only a limited number of articles is available investigating the relationship between case volume of physicians and hospitals and specialization of surgeons and survival. In summary, there is evidence to support the hypothesis that specialization, research interest, and caseload of physicians and hospitals is positively correlated with providing state-of-the-art care and with survival. However, it is less clear what impact might be attributed to the surgical routine gained with increasing number of procedures compared to the deeper insight into the biology of breast cancer that comes with specialization in oncology and the weight of the multidisciplinary setting that is more easily established and maintained with a higher caseload.