Geographic Variation in Cystoscopy Rates for Suspected Bladder Cancer between Female and Male Medicare Beneficiaries

Abstract

Objective: To assess geographic variation in cystoscopy rates among women vs men with suspected bladder cancer, lending insight into gender-specific differences in cystoscopic evaluation.

Methods: We conducted a cross-sectional study of all fee-for-service Medicare beneficiaries within 306 Hospital Referral Regions (HRRs) who received care in 2014. For each HRR, we calculated the age- and race-adjusted cystoscopy rate for women and men as our primary outcome. The rate was the number of beneficiaries who underwent cystoscopy for bladder cancer symptoms (using procedure and ICD-9 diagnosis codes) divided by all beneficiaries in the HRR. We used the coefficient of variation to compare relative variability of cystoscopy rates.

Results: Overall, 173,551 women (n = 14.8 million) and 286,090 men (n = 11.5 million) underwent cystoscopy in 2014. While women received less cystoscopies compared to men (mean 11.0 vs 23.5 per 1000, P < .001), there was greater variation in cystoscopy rates among women (coefficient of variation 27.5 vs 23.5, P = .010). When restricting to ICD-9 codes for hematuria only, women continued to demonstrate greater variation in cystoscopy rates (coefficient of variation 27.8 vs 24.2, P = .022). Findings were robust across larger HRR sizes-thereby removing some random variation seen in smaller HRRs-as well as across years 2010, 2011, 2012, and 2013.

Conclusion: Cystoscopy rates are lower in women than men, likely due to their lower bladder cancer incidence. However, there is greater variation in cystoscopy rates among women with symptoms of bladder cancer. This may reflect increased provider uncertainty whether to refer and work-up women with suspected bladder cancer.

Figure 1:

Turnip plot graphing the age- and race-adjusted cystoscopy rates among female and male Medicare beneficiaries in 2014. Each dot represents a Hospital Referral Region.

Figure 2:

Turnip plots graphing the age- and race-adjusted cystoscopy rates among female and male Medicare beneficiaries in 2014 along a Y-axis of gender-specific means. Each dot represents a Hospital Referral Region (HRR). The distribution provides a visual representation of the normalized variation in cystoscopy procedures by gender. Results are shown for all HRRs (left), those with >20,000 beneficiaries (middle), and those with >50,000 beneficiaries (right).