Insurance Status and Postoperative Mortality

Hypothesizing that insurance status may be associated with differences in specialized medical and surgical care, researchers noted that nonprivately insured patients fare worse postoperatively than privately insured patients. Those differences may be particularly evident in procedures such as hypophysectomy, lung resection, coronary artery bypass, and gastrointestinal procedures.

The researchers commented that although the mechanisms responsible for disparities related to insurance status have not been identified, if more were known about them, it might aid improved targeting of public health efforts.

Data on disparities related to insurance status in patients undergoing surgery for brain tumors is particularly limited, the researchers said. Approximately 612,000 people in the United States had a diagnosis of a primary brain or central nervous system tumor; malignant tumors cause 13,000 deaths each year and have a 5-year survival rate of approximately 5%.

To test a hypothesis that uninsured patients experience higher rates of hospital death following craniotomy for brain cancer compared with patients with private insurance, the researchers recently conducted an analysis of in-hospital mortality rates. The analysis was a retrospective cohort study utilizing the Agency for Healthcare Research and Quality’s Nationwide Inpatient Sample, January 1, 1999, through December 31, 2008. Analysis results were reported in Archives of Surgery [2012;147(11):1017-1024].

A total of 28,581 patients were included in the analysis; the 3 groups included were (1) Medicaid recipients, (2) patients with private insurance, and (3) patients who were uninsured.

Inclusion criteria were 18 to 65 years of age, an International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnosis of brain tumor, hospital admission for a craniotomy per ICD-9-CM procedural codes, and private, Medicaid, or no insurance coverage. Exclusion criteria were missing data on insurance type, race, admission type, sex, income, length of stay, and/or survival status.

Among the total cohort, 80.7% (n=23,051) had private insurance, 12.9% (n=3685) were covered by Medicaid, and 6.5% (n=1845) were uninsured. Mean age overall was 48.5 years; mean age of privately insured patients was 49.0 years, of Medicaid patients, 45.0 years, and of uninsured patients, 48.0 years. Nearly half of all patients were male (46.6%), most were white (82.0%), followed by African American (9.1%), Hispanic (7.0%), Asian/Pacific Islander (6.0%), and Native American (0.4%), a distribution similar to the US population.

Unadjusted analyses of the full study cohort found an association between lack of insurance and Medicaid coverage with higher in-hospital postoperative mortality compared with private insurance coverage. The in-hospital mortality rate for patients with private insurance was 1.3% (n=295; 95% confidence interval [CI], 1.15-1.4%) compared with 2.6% for uninsured patients (n=48; 95% CI, 1.9%-3.3%; P<.001) and 2.3% for Medicaid recipients (n=86; 95% CI, 1.8%-2.8%; P<.001).

Following adjustment for patient characteristics and stratifying by hospital in patients with no comorbidity, patients who were uninsured remained at higher risk of experiencing in-hospital death (hazard ratio [HR], 2.62; 95% CI, 1.11-6.14; P=.03) compared with patients with private insurance coverage. The disparity was not conclusively present in Medicaid recipients in the adjusted analysis (HR, 2.03; 95% CI, 0.97-4.23; P=.06).

In summary, the researchers commented, “Uninsured patients undergoing craniotomy for a brain tumor experienced worse outcomes than privately insured patients, and this difference is pronounced in teaching hospitals. This variation in postoperative outcomes remains unexplained by hospital characteristics, including clustering effects, comorbid disease, or socioeconomic variations. This study did not exclude the possibility that comorbid conditions were underdiagnosed in uninsured patients or that uninsured patients presented with more advanced stages of disease.”