Introduction:
The use of Implantable Cardioverter-Defibrillators (ICDs) varies markedly by region of the country. One possible contributor to regional variation could be variability in physicians' attitudes towards ICDs. The objective of this study was to determine if physicians' attitudes torwards ICDs vary by region.
Methods:
A national sample of 10,080 members of the American College of Cardiology were surveyed regarding their attitudes towards ICDs. The survey included a hypothetical scenario asking respondents if they would recommend an ICD to an eligible patient with ischemic cardiomyopathy, followed by questions modifying the scenario by age, sex, and frailty as well as questions measuring attitudes towards ICDs and important factors in ICD decision-making. Respondents were placed into a hospital referral region (HRR) by zip code of their practice. Data were then merged with data from the National Cardiovascular Data Registry where rates of ICD implantation were determined for all Medicare beneficiaries in a given HRR. Multivariate linear and logistic regression analyses determined associations between the regional ICD utilization rate and respondents attitudes.
Results:
We received 1210 responses (response rate 12%) with no difference between responders and non-responders with respect to physician demographics. Physicians in regions of high and low ICD use were equally likely to recommend an ICD in the 60 yo male with ischemic cardiomyopathy scenario (~99%; p = N/A). They were also equally likely to recommend an ICD if the 60 yo patient was female (~99%; p = N/A) or if the 60 yo patient had non-ischemic cardiomyopathy (85 vs. 88% p = 0.85). Multivariate analyses determined that physicians in higher utilization regions were more likely to recommend ICD therapy if the patient was ‘frail’ (32% vs. 21%; p = 0.03) or if he had a life expectancy of less than one year (10% vs 5%; p = 0.05).
Conclusions:
Even when patient-level causes of regional variation are removed through alterations in hypothetical scenarios, cardiologists in regions of high ICD use are more likely to recommend ICDs in frail patients or patients with a life expectancy of less than one year. This suggests that variations in physician attitudes may contribute to regional variations in ICD use.
Inequity of use of implantable cardioverter defibrillators in England: retrospective analysis
