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Comparing outcomes of cholecystectomies in white vs. minority patients

Open AccessPublished:August 18, 2022DOI:https://doi.org/10.1016/j.amjsurg.2022.08.006

      Highlights

      • Minority patients are more likely to be younger at admission for cholecystectomy.
      • Minority patients are more likely to require emergent cholecystectomies.
      • Minority patients more likely to have no insurance or require emergency Medi-Cal.
      • Uninsured patients have higher charges of admission and financial burden.
      • No significant difference was found for clinical outcomes between white and minority patients after admission.

      Abstract

      Background

      This study aimed to investigate the disparity between white and minority patients undergoing cholecystectomies, including presentation, outcomes, and financial burden.

      Methods

      This was an IRB approved retrospective review of all cholecystectomies at an academic medical center from 2013 to 2018. Data collected include demographics, insurance type, charge of admission, and clinical outcomes.

      Results

      1539 patients underwent cholecystectomies. Of those, 36.9% were white and 63.1% were minority. Minority patients presented at a younger age than white patients (45.5 vs 53.9, p < 0.01) and required emergent admission (76.2% vs 68.4%, p < 0.01). No significant difference was found for clinical outcomes between white and minority.
      Minority patients were more commonly uninsured (32.1%). Among the uninsured, self-pay had a higher charge than emergency MediCal (by 5.46 per 1000 dollars).

      Conclusion

      Minority patients are more commonly disadvantaged at presentation and charged more due to insurance status despite similar outcomes after cholecystectomies.

      Keywords

      1. Introduction

      Gallbladder disorders are common and costly for industrialized countries. Approximately 700,000 cholecystectomies are performed annually, and 20 million people in the United States have gallstones.
      • Riall T.S.
      • Zhang D.
      • Townsend C.M.
      • Kuo Y.F.
      • Goodwin J.S.
      Failure to perform cholecystectomy for acute cholecystitis in elderly patients is associated with increased morbidity, mortality, and cost.
      Over the last three decades, expenditures involving gallstone complications have cost the United States $6.2 billion annually via hospital charges, physician services, medications, and other aspects of care.
      • Shaffer E.A.
      Epidemiology and risk factors for gallstone disease: has the paradigm changed in the 21st century?.
      ,
      • Stinton L.M.
      • Shaffer E.A.
      Epidemiology of gallbladder disease: cholelithiasis and cancer.
      The financial burden from gallbladder disease can be attributed to environmental factors associated with socioeconomic status (SES), which result in longer length of hospital stays and an increase of post-operative complications.

      Lu P, Yang N-P, Chang N-T, Lai KR, Lin K-B, Chan C-L. Effect of Socioeconomic Inequalities on Cholecystectomy Outcomes: A 10-year Population-Based Analysis. doi:10.1186/s12939-018-0739-7.

      ,
      • Diehl A.K.
      • Rosenthal M.
      • Hazuda H.P.
      • Comeaux P.J.
      • Stern M.P.
      Socioeconomic status and the prevalence of clinical gallbladder disease.
      Furthermore, uninsured minority individuals may forgo seeking treatment until later stages of the disease.

      Neureuther SJ, Nagpal K, Greenbaum A, Cosgrove JM, Farkas DT. The Effect of Insurance Status on Outcomes after Laparoscopic Cholecystectomy. doi:10.1007/s00464-012-2675-8.

      Therefore, its crucial to investigate the barriers that impact minority populations in seeking treatment for gallbladder disease.
      Cholecystectomies performed to treat gallbladder disease can be either laparoscopic or open procedures. As delayed care for gallbladder disease can lead to a number of complications, patients are advised to seek treatment before their symptoms become worse and subsequently necessitate an open procedure, thus losing the opportunity to undergo a laparoscopic procedure.

      Neureuther SJ, Nagpal K, Greenbaum A, Cosgrove JM, Farkas DT. The Effect of Insurance Status on Outcomes after Laparoscopic Cholecystectomy. doi:10.1007/s00464-012-2675-8.

      ,
      • Johnstone M.
      • Marriott P.
      • Royle T.J.
      • et al.
      The Impact of Timing of Cholecystectomy Following Gallstone Pancreatitis 5.
      However, this treatment option may not be available for uninsured patients or patients of minority background as socioeconomic limitations and health insurance status may restrict their access to necessary primary healthcare.

      Lu P, Yang N-P, Chang N-T, Lai KR, Lin K-B, Chan C-L. Effect of Socioeconomic Inequalities on Cholecystectomy Outcomes: A 10-year Population-Based Analysis. doi:10.1186/s12939-018-0739-7.

      As a result, minority and uninsured patients are often at a far greater disadvantage compared to non-minority and insured individuals when measuring outcomes of healthcare.
      • Diehl A.K.
      • Rosenthal M.
      • Hazuda H.P.
      • Comeaux P.J.
      • Stern M.P.
      Socioeconomic status and the prevalence of clinical gallbladder disease.
      This disparity may also lead to higher risks of intra-operative and post-operative complications for patients seeking treatment.
      • Carbonell A.M.
      • Lincourt A.E.
      • Kercher K.W.
      • et al.
      Do patient or hospital demographics predict cholecystectomy outcomes? A nationwide study of 93,578 patients.
      We suspect these differences in access to healthcare and overall outcomes of medical treatment are a result of a larger multifactorial cause for disparity, including gender, race/ethnicity, health insurance status, location of residence, the severity of illness upon admission, and age. Numerous studies have also associated an increase of complications to socioeconomic inequalities. For example, Lu et al. report patients with disadvantaged backgrounds to be more susceptible to risks involving cholecystectomy procedures.

      Lu P, Yang N-P, Chang N-T, Lai KR, Lin K-B, Chan C-L. Effect of Socioeconomic Inequalities on Cholecystectomy Outcomes: A 10-year Population-Based Analysis. doi:10.1186/s12939-018-0739-7.

      Diehl et al. suggest that environmental factors like education, income and insurance status play a role in gallbladder prevalence.
      • Diehl A.K.
      • Rosenthal M.
      • Hazuda H.P.
      • Comeaux P.J.
      • Stern M.P.
      Socioeconomic status and the prevalence of clinical gallbladder disease.
      This study intends to focus on the possible influence of insurance status on healthcare disparities in our greater analysis of minority versus white individuals who undergo a cholecystectomy procedure.
      The objective of this study is to evaluate disparities in presentation and outcomes between minority versus white individuals via cholecystectomies, as well as the factors that contribute to this disparity. Health care access was evaluated under the assumption that it correlates to insurance status.
      Cholecystectomies are suitable procedures to investigate differences between white/minority and insured/uninsured individuals because patients with limited primary health care access, regardless of ethnicity, are more prone to health conditions that increase the need for gallbladder removal, particularly acute procedures.

      Neureuther SJ, Nagpal K, Greenbaum A, Cosgrove JM, Farkas DT. The Effect of Insurance Status on Outcomes after Laparoscopic Cholecystectomy. doi:10.1007/s00464-012-2675-8.

      As previously shown, whether a surgical procedure is emergent or routine influences patient well-being, as emergent cholecystectomies have a significant correlation with morbidities and even mortality.
      • Ambur V.
      • Taghavi S.
      • Kadakia S.
      • et al.
      Does socioeconomic status predict outcomes after cholecystectomy?.
      Moreover, studies have shown a correlation between ethnicity and the treatment provided for gallstone disease, i.e. whether or not a patient undergoes same admission cholecystectomy as per national guidelines.
      • Nguyen G.C.
      • Tuskey A.
      • Jagannath S.B.
      Racial disparities in cholecystectomy rates during hospitalizations for acute gallstone pancreatitis: a national survey.
      ,
      • Everhart J.E.
      • Khare M.
      • Hill M.
      • Maurer K.R.
      Prevalence and ethnic differences in gallbladder disease in the United States.
      It is also known that in general, uninsured patients have poorer overall health and require a greater number of health care services (doctor's visits, hospital admissions, etc.) than insured patients.
      • Mcwilliams J.M.
      Currently, there are limited studies evaluating the correlation between routine primary care treatment, decreased emergent cholecystectomies, and lower rates of post-operative morbidities and mortality. Due to the disparity of healthcare access, we hypothesize that minority patients are typically uninsured and have a higher rate of emergent admission for cholecystectomy operations and subsequently, worse post-operative outcomes.

      2. Methods

      An IRB approved (HS#2018–4576) retrospective analysis was done for all cholecystectomies performed at the University of California, Irvine Medical Center, a 465-bed academic medical center, between July 2013 and October 2018. All patients age ≥17 who underwent cholecystectomies were identified using all International Classification of Diseases version-9 (ICD-9) procedure codes pertaining to cholecystectomies. In order to focus our investigation on the outcomes of patients with primary gallbladder disease, patients who received cholecystectomies as part of a larger procedure, such as pancreaticoduodenectomies, were then excluded. Data collected include demographics, insurance type, emergent versus non-emergent admission, charge of admission, complications, and length of stay (LOS) and intensive care unit (ICU) LOS. Minority was defined as non-white and included Hispanic, Asian, Black/African-American, and Native Hawaiian or other Pacific Islander.
      Insurance status was categorized as Managed MediCal, Commercial/Contracts/Private, MediCare/Managed MediCare/County, and None/Self-Pay/MediCal. Commercial, Contracts, and Private insurance were combined into a single group due to the low number of subjects in each individual category. In the state of California, MediCal can be either issued for those with qualifying income or granted as emergency insurance for uninsured patients. For the purposes of this study, Managed MediCal was considered standing insurance while MediCal was considered emergency insurance for the uninsured.
      The primary outcomes were morbidity, mortality, and charge of admission. Morbidity was defined by intra-operative and post-operative complications during index admission. Due to the low number of subjects who expired, a statistical analysis of mortality could not be performed. A comparison was then made for patients who had a disposition other than home, including skilled nursing facility (SNF), acute care facility, short-term inpatient care, and expired. Other measured outcomes included charge of admission, LOS, and ICU LOS. Intraoperative complications were determined via individual chart review and included unexpected bleeding requiring intraoperative repair, injury to nearby structure, failed stone removal, and delayed wound closure. Postoperative complications were determined via chart review of the same hospitalization and included bleeding, surgical site infection, sepsis, pneumonia, ulcer, ileus, urinary retention, bile leak, and organ failure. Charge of admission was defined as the hospital charges associated with the admission during which the cholecystectomy was performed.
      Charge of admission was capped at $1 M due to some outliers that were influential on the models (10 changes were made). Similarly, LOS was capped at 60 days (5 changes were made).
      Chi square and t-tests, as well as linear and logistic regression models, were utilized for analysis. Qualitative variables were coded as absent or present. Regression models were used to model total cost, LOS, post-operative mortality, as well as pre- and post-operative complications. Logistic regression models were used to model the dichotomous outcomes postoperative complications and morbidity/mortality. Linear regression models were used to model continuous hospitalization outcomes, total charge, and LOS. The main predictors of interest were race/ethnicity and insurance status. We adjusted for potential confounders including age, gender, admission type, and conversion procedure.
      Predictors of outcome were reported with an odds ratio (OR) with 95% confidence intervals (CI). Differences of p < 0.05 were considered statistically significant. All statistical analyses were conducted using Stata/IC 16.1 (StataCorp. 2019. Stata Statistical Software: Release 16. College Station, TX: StataCorp LLC).

      3. Results

      3.1 Demographics

      Of the 1539 patients who underwent cholecystectomies for primary gallbladder disease, 36.9% were white and 63.1% were minority. In both groups, the majority of patients were female (58.6% and 67.6% respectively, Table 1). Minority patients were younger than white patients at the time of admission for surgical intervention (45.5 vs 53.9, p < 0.01, Table 1).
      Table 1Demographics, admission and procedure information, and outcomes by race/ethnicity group, White (n = 568) and Minority (n = 971). Total n = 1539. Minority is comprised of Hispanic, Asian, Black/African-American, and Native Hawaiian or Other Pacific Islander. Unknown indicates there was not sufficient data available for the particular subject in the specific variable.
      VariableN (%) or Mean (SD)P-value
      WhiteHispanic/Asian/Black/Native Hawaiian
      Age53.9 (16.2)45.5 (17.1)<0.001
      Gender<0.001
       Female333 (58.6)656 (67.6)
       Male235 (41.4)315 (32.4)
      Insurance<0.001
       Managed MediCal79 (13.9)239 (24.6)
       Commercial/Contracts/Private278 (48.9)240 (24.7)
       Medicare/Managed Medicare/County171 (30.1)180 (18.5)
       Self/None/MediCal37 (6.5)312 (32.1)
       Unknown3 (0.5)0 (0)
      Emergent Admission385 (68.4)736 (76.2)0.001
      Procedure<0.001
       Laparoscopic449 (79.0)861 (88.7)
       Open90 (15.8)73 (7.5)
       Conversion26 (4.6)36 (3.7)
       Unknown3 (0.5)1 (0.1)
      Length of Stay (in days)4.8 (5.7)4.4 (5.2)0.42
      Days in the ICU (continuous)0.42 (5.9)0.15 (1.2)0.54
      Charge (in Dollars)101,692 (128,667)80,431 (100,818)0.03
      Number of Intraoperative Complications0.16
       0519 (91.4)909 (93.6)
       145 (7.9)59 (6.1)
      Unknown4 (0.7)3 (0.3)
      Number of Postoperative Complications0.07
       0495 (87.1)884 (91.0)
       166 (11.6)77 (7.9)
       24 (0.7)7 (0.7)
       30 (0.0)1 (0.1)
       Unknown3 (0.5)2 (0.2)
      Disposition0.37
       Home534 (94.0)933 (96.1)
       SNF17 (3.0)16 (1.6)
       Acute Care Facility9 (1.6)8 (0.82)
       Discharged Elsewhere1 (0.18)4 (0.41)
       Left Against Medical Advice2 (0.35)3 (0.31)
       Expired1 (0.18)2 (0.20)
       Short-term Inpatient Care0 (0)3 (0.31)
       Unknown4 (0.70)2 (0.20)

      3.2 Type of admission and procedure

      Emergent admission was significantly higher in minority than white patients (76.2% vs 68.4%, p < 0.01, Table 1). Minority patients were more likely to undergo laparoscopic procedures compared to their white counterparts (88.7% vs 79.0%, p < 0.01).

      3.3 Morbidity/mortality

      No significant difference was found between whites versus minority in hospital length of stay (4.8 vs 4.4 days, p = 0.42, Table 1) or ICU LOS (0.4 vs 0.2 days, p = 0.54, Table 1). The percentage of patients admitted to the ICU for white patients was 5.3% and for minority patients was 3.4%, a relatively low percentage of overall patients. No significant difference was found between whites versus minority for intraoperative (p = 0.16) or postoperative (p = 0.07) complications. No significant difference was found between disposition to home versus disposition to care facility/expiration (OR 0.89, CI 0.50–1.60, p = 0.71, Table 2).
      Table 2Multivariable logistic regression results for disposition outcome on Race/Ethnicity and Insurance Status, adjusted for Age, Gender, Conversion, and Emergent Admission.


      Variable
      Morbidity/MortalityP-value
      Adjusted Odds Ratio95% Confidence Interval
      Race/ethnicity
       White1.0 (ref)
       Minority0.890.50–1.600.71
      Insurance
       Managed MediCal1.410.42–4.700.58
       Commercial/Contracts/Private1.590.51–4.960.43
       Medicare/Managed Medicare/County5.221.63–16.750.005
       Self/None/MediCalREFERENCE

      3.4 Insurance and charge

      The most common insurance type in white patients was private/contract/commercial insurance (48.9%) while the majority of minority patients were uninsured (self-pay, none, MediCal; 32.1%). A greater number of minority patients were uninsured compared to whites (32.1% vs 6.5%, Table 1). The charge for uninsured patients was lower than that of patients with commercial/contract/private insurance and Medicare (by 27.8 per 1000 dollars, 39.3 per 1000 dollars respectively, p < 0.001, Table 3). Among uninsured patients, the charge for patients with no insurance or self-pay was higher than that of patients with emergency MediCal insurance (by 5.46 per 1000 dollars, Table 4).
      Table 3Multivariable linear regression results for Total Charge (per 1000 dollars) outcome on Race/Ethnicity and Insurance Status, adjusted for Age, Gender, Conversion, and Emergent Admission.
      VariableTotal ChargeP-value
      Estimate95% Confidence Interval
      Race/ethnicity
       White(ref)
       Minority−11.6−23.5, 0.290.056
      Insurance
       Managed MediCal12.0−4.2, 28.20.15
       Commercial/Contracts/Private27.811.4, 44.20.001
       Medicare/Managed Medicare/County39.319.2, 59.3<0.001
       Self/None/MediCalREFERENCE
      Table 4Multivariable linear regression results for Total Charge (per 1000 dollars) outcome on Race/Ethnicity and Insurance Status, adjusted for Age, Gender, Conversion, and Emergent Admission, sub-analysis between emergency MediCal and None/Self-Pay.
      VariableTotal ChargeP-value
      Estimate95% Confidence Interval
      Insurance
       MediCal−5.46−34.21, 23.290.71
       Self/NoneREFERENCE

      4. Discussion

      In this retrospective analysis of patients who underwent cholecystectomies in a five year period, minority patients were significantly younger at presentation and more likely to require emergent admission. Contrary to our hypothesis, there was no significant difference in the length of stay, ICU length of stay, or intraoperative and postoperative complications. As such, our data shows an emphasis on pre-operative disparities as patients receive comparable quality of care once admitted.
      In support of our hypothesis, minority patients were more likely to be uninsured or require emergency MediCal compared to their white counterparts. Although not statistically significant, uninsured (no insurance/self-pay) patients had a trend of higher charge than that of patients who required emergency MediCal. As such, having emergency insurance is financially favorable to no insurance at all.
      On the other hand, patients with no insurance/self-pay had significantly lower charges than that of patients with private insurance and Medicare. This should be interpreted in the context of charge as opposed to cost. This analysis used charge for comparison of financial impact of treatment, hence requiring consideration of components that contribute to total charge. Patients with private/commercial/contract insurance are likely to have a higher total charge of admission based on the premise that private insurers will pay only a proportion of the total bill. However, these patients are only required to pay the deductible before the rest of the charge is covered by insurance, further decreasing the financial burden on the patient. On the other hand, patients who qualify for Medicare must meet eligibility requirements, including age over 65, disability, or kidney dialysis and transplant. As such, patients with Medicare have a greater number of health conditions and comorbidities at baseline, requiring additional care during admission that adds to total charge. Moreover, as Medicare covers approximately 80% of hospital bills, patients with Medicare insurance are only responsible for 20% of the total charge while no insurance/self-pay patients need to pay for 100% of their bills. To this effect, the burden of the hospital bill is substantially heavier for the uninsured.
      The impact of insurance status on healthcare outcomes is an ongoing topic of research. Studies have consistently shown that minority and uninsured patients are disadvantaged when receiving care for gallbladder disease. Greenstein et al. found that acute cholecystitis patients with Medicaid were less likely to receive cholecystectomies on admission than those with private insurance and were more likely to have open or laparoscopic-converted-open cholecystectomies.
      • Greenstein A.J.
      • Moskowitz A.
      • Gelijins A.C.
      • Egorova N.N.
      Payer status and treatment paradigm for acute cholecystitis.
      Additional studies found that uninsured patients are more likely to undergo an emergent procedure and have a longer LOS and more complications

      Neureuther SJ, Nagpal K, Greenbaum A, Cosgrove JM, Farkas DT. The Effect of Insurance Status on Outcomes after Laparoscopic Cholecystectomy. doi:10.1007/s00464-012-2675-8.

      ,
      • Carbonell A.M.
      • Lincourt A.E.
      • Kercher K.W.
      • et al.
      Do patient or hospital demographics predict cholecystectomy outcomes? A nationwide study of 93,578 patients.
      ,.
      • Schwartz D.A.
      • Hui X.
      • Schneider E.B.
      • et al.
      Worse outcomes among uninsured general surgery patients: does the need for an emergency operation explain these disparities?.
      Similarly, Ambur et al. evaluated the outcomes of cholecystectomies based on income quartile and found that patients of the lowest quartile were more likely to have Medicaid insurance and higher rates of mortality and postoperative complications.
      • Ambur V.
      • Taghavi S.
      • Kadakia S.
      • et al.
      Does socioeconomic status predict outcomes after cholecystectomy?.
      On the contrary, the results of our study do not mirror these significant differences in clinical outcomes, including length of stay and complications, between insured and uninsured based on our association of whites as insured and minority as uninsured. However, similar to our findings, those of the lowest quartile were more likely to be of minority descent and younger at age of presentation.
      Furthermore, in the discussion of the white versus minority patients, it is vital to consider the underlying disparities of health that fuel these results. Gallbladder disease is a common ailment that can result from a number of factors. Although there are nonmodifiable factors such as age and gender, there are also modifiable factors such as diet. This, combined with the finding that minority patients present at younger ages, raises the need to investigate ingrained disparities that start earlier in a patient's lifetime. For instance, studies show that lowest-income highest-minority neighborhoods had the most significant declines in convenience stores over time, hence limiting the availability and access of these communities to healthy foods.
      • Ohri-Vachaspati P.
      • DeWeese R.S.
      • Acciai F.
      • et al.
      Healthy food access in low-income high-minority communities: a longitudinal assessment—2009–2017.
      Similarly, health literacy is key to preventative health but often limited in minority populations. This may be due to many reasons including education, resources, and language barriers.
      • Fransen M.P.
      • Harris V.C.
      • Essink-Bot M.
      Low health literacy in ethnic minority patients: understandable language is the beginning of good healthcare.
      ,
      • Nesbitt S.
      • Palomarez R.E.
      Review: increasing awareness and education on health disparities for health care providers.
      In order to address the health and insurance disparities faced by minority populations, a comprehensive evaluation is necessary to account for the social determinants of health in this multifactorial problem.
      The findings of this study should be interpreted in light of its limitations. Our investigation included 1539 cholecystectomies performed at an academic medical center over the course of five years. When determining the categories of insurance, several types were combined due to the low number of individuals in each group. Private insurance was combined with commercial/contract insurance despite the former being associated with personal insurance and the latter associated with employment. However, given that they are both managed by a private insurance company, they were treated as one category. County insurance was grouped with Medicare and managed Medicare as they are all state-sanctioned insurance. Similarly, a total of 3 patients expired post-operatively, which is insufficient data to perform meaningful analysis and prevented us from comparing the mortality rates between minority and white patients. A larger multicenter study with an extended timespan may provide a greater number of subjects and better insight to the relationship between race, insurance status, and outcomes. Another limitation is the utilization of charge to compare financial impact of insured versus uninsured admissions. Charge may fluctuate depending on the patient's overall health condition. A patient with multiple comorbidities requires more healthcare services during an admission than an otherwise healthy patient presenting solely with a gallbladder complaint. Future studies may consider the cost of admission, which quantifies the actual amount of money collected for each admission. It may also be beneficial to further investigate the number of previous visits a patient has made for the same chief complaint to better understand the total cost burden for the disease process. Finally, the retrospective nature of this study posed limitations. As patients were identified via ICD-9 procedure codes and complications identified via chart review, reporting and coding error may be present. Similarly, additional data, including reasons for open or conversion to open procedure are heavily dependent on surgeon preference and difficult to account for in a retrospective study. As such, we were unable to quantitate this factor into our study.

      5. Conclusion

      Multiple factors contribute to the clinical outcome and financial burden of healthcare in patients who identify as minority. Minority patients present younger and are more likely to require emergent admission for cholecystectomies than their white counterparts. Once admitted, the care they received resulted in similar clinical outcomes. They are also more likely to be uninsured, resulting in higher charges associated with the management of the same condition.
      Continued efforts to improve rates of healthcare coverage and education should be evaluated in an effort to reduce differences associated with the presentation and treatment of gallbladder disease between white and minority patients.

      Declaration of competing interest

      The authors of this study certify that they have NO affiliations with or involvement in any organization or entity with any financial interest in the subject matter or materials discussed in this manuscript.

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