Geography Lessons: Scrutinizing State-by-State Differences in Inpatient Gastroparesis Care

Gastroparesis is defined as a slowing of gastric emptying, a condition that has been associated with nausea, vomiting, and related symptoms. Few papers have addressed its prevalence and incidence and have characterized factors related to health care utilization for this condition. A recent population-based analysis reported prevalence per 100,000 for definite gastroparesis (defined by typical symptoms with documented delayed gastric emptying) of 9.6 for men versus 37.8 for women [1]. Age-adjusted incidences per 100,000 person-years calculated from the same population were 2.4 for men and 9.8 for women. Nevertheless, these data may not be generalizable due to its unique locale, Olmsted County, Minnesota, a highly educated, relatively homogeneous population medically well served by the Mayo Clinic. Furthermore, the impact of geography, demographics, and socioeconomic factors on hospitalization rates for gastroparesis and on other parameters of health resource usage has not heretofore been reported in the medical literature. The article by Bielefeldt in this issue represents an important addition to the literature, providing voluminous new information relating to regional profiles of inpatient care for gastroparesis (Table 1). The study utilized the State Inpatient Databases, which accumulate demographic and clinical information from 90 % of hospitalizations in 46 states. For this investigation, the International Diagnosis Code (ICD-9) for gastroparesis (536.3) was queried from 2007 through 2010 for 35 states. The most striking findings were the greater-than-fourfold differences in admission rates for this condition. It is possible that states with high admission percentages are the main contributors to the previously reported increase in hospitalizations for gastroparesis [2]. Twofold geographic differences in length of stay and nursing home transfers were also observed. Among demographic factors, higher hospitalization rates were related to female sex, greater state population, lower incomes, admission to large centers, and Medicare coverage. Clinically, heart failure was associated with increased admissions, whereas diabetes was inversely related to hospitalizations. Admission data correlated roughly with rates of endoscopy and in older individuals, gastrostomy placement, both of which also showed wide state-to-state variability. Conversely, enteral or parenteral nutrition initiation did not strictly relate to hospitalization rates. Finally, higher numbers of overall admissions but lower percentages of admissions with gastroparesis as a primary diagnosis were associated with inpatient mortality as were age [65 years, female sex, poverty, and endoscopies. The author concluded that disease-dependent and socioeconomic factors contribute to regional differences in inpatient health care for gastroparesis. Although the analyses by Bielefeldt were broad-ranging, other administrative factors related to differences in coding may have contributed to apparent regional variations in inpatient care of gastroparesis. The author did attempt to address this issue by comparing ICD-9 coding for gastroparesis versus dyspepsia. Yet, annual admissions for dyspepsia were only 2–3 % of those for gastroparesis in this study. Although hospitalization data for functional dyspepsia are lacking for the United States, its prevalence in the community exceeds 5 % and its inpatient costs are greater than threefold higher than for non-dyspeptics [3]. Thus, it is likely the coding of this disorder within this database did not consistently capture all functional W. L. Hasler (&) Division of Gastroenterology, University of Michigan Health System, 3912 Taubman Center, 5362, Ann Arbor, MI 48109, USA e-mail: whasler@med.umich.edu; whasler@umich.edu