Discussion:
The present study is the first and the largest to assess the outcomes of ESRD with LGIB. We analyzed 2187954 admissions from the NIS database to examine outcomes of ESRD among the patients with LGIB. To compare outcomes of ESRD among patients with LGIB versus ESRD patients, we used a propensity-matched model. This model allowed us to account for confounding factors and reduce the effect of selection bias. The in-hospital mortality was higher in ESRD patients with LGIB group. This group has higher odds of requiring mechanical ventilation and vasopressor for the shock. Advanced age, acute coronary syndrome, anemia, acute respiratory failure, mechanical ventilation, and sepsis were identified as predictors of mortality in this group. Mean LOS and mean total charges were also higher in this group.
ESRD is a growing public health problem with number tripled between 1990 and 2010. ESRD patients have a higher tendency to develop LGIB. As the primary etiological factors (diabetes and hypertension) for ESRD are increasing, there will be an increasing rate of ESRD, which might as well increase the case of GIB related to ESRD. [6 20] ESRD patients are likely to bleed more due to a variety of causes, which include heparin used during dialysis, platelet dysfunction, and medications. [7 11 12] It is essential to understand that LGIB in ESRD patients could be due to a variety of causes. [21] The most common cause of bleeding is angiodysplasia. The other causes are diverticulosis, hemorrhoids, stercoral ulcer, and ischemic colitis. Due to many pathophysiology and locations of bleeding, ESRD patients who develop acute LGIB require a thorough evaluation.
In 2016, there were 35.7 million hospital stays in the United States, and the cost of these stays totaled over $417 billion, with a mean cost per stay of $11,700 [22]. Hospitals and health systems across the nation are under pressure to avoid patient harm and to reduce the length of stay (LOS) [23]. A longer LOS also increases the likelihood of a hospital-acquired condition (HAC), which harms patients and contributes to an even costlier and longer stay [24 25]. The mean LOS is higher among ESRD patients with LGIB compared to ESRD patients. Our findings are consistent with previous studies which have shown that the patients with CKD have an average hospital length of stay (LOS) that is 2 to 3 days longer compared to the general population [26 27]. Increased LOS results in increased cost of a stay in the hospital. Our results show that the mean cost of hospitalization in ESRD patients who develop LGIB is 19000 $ more compared with ESRD patients. Early identification and intervention would be prudent to reduce the length and cost of the stay.
Many studies have shown increased mortality for ESRD patients with GIB. The all-cause mortality of ESRD patients hospitalized for UGIB is significantly high, with the first-month mortality of 11 to 14%, and the one-year mortality could go up to 27%. [28 29] There is limited data available for ESRD patients hospitalized for LGIB. A study by Trivedi et at; showed an episode of hospital-associated gastrointestinal bleeding in long-term dialysis patients could increase the hazard of death by two-fold [5]. Our findings show that ESRD patients who get hospitalized for LGIB are likely to have more mortality (OR 1.3, 95% CI 1.2-1.3; P=0.00) compared with ESRD patients. ESRD patients have many comorbid conditions and higher mortality due to cardiovascular disease. Cardiovascular events may increase after gastrointestinal bleeding causing hemodynamic insult or decline in hemoglobin [5]. GIB would cause hypovolemia. Hypovolemia from any cause increases mortality in the patients hospitalized for GIB. [30] To reduce mortality in ESRD patients with LGIB, early volume resuscitation, and adequate blood transfusion might be necessary. Also, in the patient with a history of coronary artery disease, the optimization of risk factors and medicines is of very high value to reduce mortality.
ESRD patients who are hospitalized for LGIB have higher odds of requiring mechanical ventilation (OR 1.4, 95% CI 6.4-16.4; P=0.00) and vasopressor for shock (OR 1.2, 95% CI 4.9-5.4; P=0.002). These could be reasoned as these patients have many comorbidities, and they are likely to get sicker quickly. [30] We hypothesized that patients with ERSD and LGIB have a longer LOS and likely to develop more complications. Complications like cardio-respiratory failure and sepsis would require them to need more ventilator and vasopressor support. Early identification of shock, volume status, and sepsis would be prudent to improve outcomes in ESRD patients and LGIB.
In this study, we have identified a few predictors for increased mortality in ESRD patients who get hospitalized for LGIB. These predictors are advanced age (OR 1.02 CI 1.02-1.03 P=0.00), anemia (OR 1.04 CI 1.59-1.91 P=0.006), acute coronary syndrome (OR 1.8 CI 1.6-2.1, P=0.00), acute respiratory failure (OR 1.29 CI 2.0-2.6, P=0.00), mechanical ventilation (OR 1.9, CI 3.5-4.4, P=0.00), and sepsis (OR 1.5, CI 4.1-5.08, P=0.00). ESRD patients have a high number of comorbid conditions. One study for LGIB has shown that in-hospital mortality increased > 7 % with comorbid score ≥ 2 vs. 1.7% for those with no comorbidities [30]. We are going to emphasize the importance of recognizing that ESRD patients who get hospitalized for LGIB need close attention as they have a higher likelihood of becoming sicker and dying while hospitalized. These predictors could help in the future to create a risk score to identify high-risk patients earlier during hospitalization.
The primary limitation of the study is the cross-sectional design of the data, which does not allow longitudinal follow-up of patients, limiting us from incorporating a temporal effect into our analysis. Second, the NIS contains hospitalization records and not individual patients implying that adjusting for multiple hospitalizations was impossible. Despite these limitations, our study diminishes bias similarly to a randomized trial by including a wide array of covariates in both our propensity matching algorithm and our final models. We were able to provide the results of a large cohort composed of patients from numerous institutions, all geographic regions, economic and demographic groups in the USA. Therefore, our results could be generalized to the USA population.
In summary, ESRD patients who get hospitalized for LGIB are sicker than we believe. They have a higher chance of requiring critical care support leading to increased length of stay and cost for care. These patients have a higher tendency to bleed, and they bleed more due to a variety of insults, and due to a few different causes. Clinicians are compelled to have a broader knowledge of this clinical entity as the management of these patients involves a variety of tests and treatments. In the future, developing a risk score to identify the high-risk patients would be of help.
Table 1. Demographicscomparing ESRD with LGIB vs. ESRD only.