We found substantial racial differences in the utilization of PN for malnourished IBD patients in the hospital setting. Because nutritional support is an important adjunct to medical therapy, our findings suggest potential differences in quality of care. Complications from PN were also observed at higher rates among Hispanics compared to non-Hispanic whites.
Disparities may arise at one or more of several steps required for the initiation and maintenance of PN. The first challenge is the recognition and evaluation of protein-calorie malnutrition. Racial disparities have been described in nutritional evaluation for other chronic diseases such as diabetes mellitus (12
). The longer time interval to initiation of PN among African Americans and Hispanics supports the possibility that recognition of malnutrition may be more delayed in minorities.
The placement of indwelling intravenous catheters for PN is a commonly performed procedure and thus access to surgeons and interventional radiologists is not a rate-limiting factor. However, there may be racial differences in access to hospitals that have ancillary multidisciplinary nutrition management teams that are crucial for both the evaluation and continued management of malnutrition. In addition, patients who are started on PN require supportive care to maintain their venous catheters and nutrition infusions. This posthospitalization long-term care requires an infrastructure for collaboration with home care agencies that may not be widely available. In our study, patients hospitalized in urban settings were more likely to receive parenteral nutrition, though this difference was only marginally significant. Complications from PN, particularly catheter-related infections, are reduced when nurse clinical nutritionists or dedicated nutrition support teams participate in patient care (13
). Thus, the higher rate of catheter infections among Hispanics receiving parenteral nutrition may also suggest lower access to a nutritional support infrastructure.
Differential access to hospitals that have the infrastructure and multidisciplinary resources for PN may be a common contributing factor to both racial and geographic variations PN utilization. The Northeast was four-fold more likely to use PN than the West. These regional disparities in the management of malnutrition may also reflect differences in practice patterns and physician preferences toward procedural interventions between different geographic areas of the country. The Northeast not only had the highest rate of PN but also the lowest rate of colectomy (6
). There are potential financial barriers to receiving nutritional support as evidenced by our findings of less frequent PN among those who resided in lower income neighborhoods and those who were uninsured. In-hospital charges are nearly twice as high for IBD patients receiving PN compared to those who did not, even after adjustment for demographic and clinical factors (15
). These findings likely underestimate the true economic consequences associated with PN because they do not include outpatient costs associated with home care.
The analysis of administrative datasets has several limitations. First, the study relies on identification of IBD cases and PN utilization through ICD-9-CM coding which we are unable to validate by chart review. However, we would expect any coding inaccuracies would be non-differential with respect to race. In most cases, this non-differential misclassification leads to attenuation and masking of observed effects, but should not compromise inferences from associations that are actually detected (16
). In addition, though malnutrition is a clinical indication for initiation of PN, such decisions may also be influenced by disease severity. Though NIS data allow us to assess comorbidity, we cannot assess disease-specific measures of severity for either Crohn’s disease or ulcerative colitis. It is also possible that if hospitalized African Americans who are malnourished may be better able to tolerate enteral feeds and require PN less often. Unfortunately, enteral feeding is not reliably captured in the NIS dataset because it is infrequently billed as a procedure. Thus, this interesting hypothesis cannot be answered by administrative data and can only be addressed by prospectively collected data.
We have provided exploratory evidence for racial and geographic disparities in the use of parenteral nutrition for hospitalized IBD patients with malnutrition that may have implications for inequities in delivery of IBD healthcare. The impact of these disparities on health outcomes is unknown, especially since the efficacy of parenteral nutrition in IBD remains unproven (17
). This study likely underestimates the extent of racial disparities since our study population contained individuals who already had a diagnosis of malnutrition. It is possible that there may be greater disparities in the recognition and diagnosis of malnutrition. Future studies must collect prospective data to assess disparities in diagnosis of nutritional deficiencies as well as delineate the mechanisms of racial and geographic variation in PN implementation. The ultimate goal would be to establish multidisciplinary nutritional intervention teams that would eliminate health disparities in treatment of IBD.