Black Women in the US Military Face Longer Surgery Delays Than White Women

Results from a study of the US Military Health System (MHS) show that non-Hispanic black (NHB) women endured longer durations until surgery than non-Hispanic white (NHW) women, but these delays in surgery did not explain observed racial disparities in survival and prompt further research, according to the investigators (JAMA Surg. 2019 Jan 23. Epub ahead of print).

“Racial disparities in time to surgery (TTS) after a breast cancer diagnosis and whether these differences account for disparities in overall survival have been understudied in the US population,” explained lead investigator Yvonne L. Eaglehouse, PhD, MPH, John P. Murtha Cancer Center, Uniformed Services University and Walter Reed National Military Medical Center, Bethesda, Maryland, and colleagues.

Using information from the Department of Defense Central Cancer Registry and MHS Data Repository linked databases that spanned from January 1, 1998, to December 31, 2008, Dr Eaglehouse and colleagues retrospectively compared TTS in NHB and NHW women with breast cancer (mean age, 50 years) and sought to determine whether racial differences in TTS could potentially explain racial disparities in overall survival in a universal healthcare system.

Ultimately, the study included 988 NHB women and 3899 NHW women with breast cancer stage I to III who underwent breast-conserving surgery (BCS) or mastectomy in the US MHS during the study period. Dr Eaglehouse and colleagues conducted data analyses from July 5, 2017, to December 29, 2017.

The primary end point of the trial was time to breast cancer surgery, and black and white patient cohorts were compared at the 25th, 50th (median), 75th, and 90th percentiles of TTS via multivariable quantile regression.

To estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause death between NHB and NHW women, the investigators used Cox proportional hazards regression models and controlled for potential confounders with and without TTS.

Findings demonstrated a median TTS of 21 days (95% CI, 20.6-21.4 days) and 22 days (95% CI, 20.6-23.4 days) among NHW and NHB women, respectively. According to multivariable models, at the 75th (3.6 days; 95% CI, 1.6-5.5 days) and 90th (8.9 days; 95% CI, 5.1-12.6 days) percentiles, NHB women had a significantly longer estimated TTS than NHW women. The estimated differences were similar by surgery type.

In addition, the adjusted risk for death was higher in NHB women (HR, 1.45; 95% CI, 1.06-2.01) than NHW women, particularly among recipients of breast-conserving surgery.

Of note, the risks were similar between NHB and NHW women who underwent mastectomy (HR, 1.06; 95% CI, 0.76-1.48); similar HRs persisted after TTS was added to the Cox proportional hazards regression models.

“This study's results indicate that time to breast cancer surgery was delayed for NHB compared with NHW women in the Military Health System,” Dr Eaglehouse and colleagues concluded.

“However, the racial differences in TTS did not explain the observed racial differences in overall survival among women who received breast-conserving surgery,” they added.—Hina Khaliq