Costs of Care for Hospitalization for Pemphigus in the United States.

IMPORTANCE

Pemphigus is an autoimmune blistering disorder associated with significant morbidity and mortality. However, little is known about the inpatient burden of pemphigus.

OBJECTIVE

To determine the incidence of and risk factors for hospitalization with pemphigus and cost of care.

DESIGN, SETTING, AND PARTICIPANTS: The 2002-2012 Nationwide Inpatient Sample provided by the Healthcare Cost and Utilization Project from the Agency for Healthcare Research and Quality was analyzed. A total of 87 039 711 children and adults (mean [SD] age, 57.7 [0.98] years for those with a primary diagnosis of pemphigus; 70.6 [0.32] years for those with a secondary diagnosis of pemphigus; and 47.9 [0.19] years for those without a diagnosis of pemphigus) were studied. Data analysis was performed from June 1 to August 30, 2015.

MAIN OUTCOMES AND MEASURES

Hospitalization rates, length of stay, and cost of care.

RESULTS

There were 1185 and 5221 patients admitted with a primary or secondary diagnosis of pemphigus, respectively; when factoring in weights that generalize the sample to the entire hospitalized US cohort, these admissions represented weighted frequencies of 5647 and 24 880, respectively. In multivariable logistic regression models with stepwise selection, increasing age (adjusted odds ratios [95% CIs]: 18-39 years: 5.53 [4.28-7.14], P < .001; 40-59 years: 10.98 [8.46-14.24], P < .001; 60-79 years: 7.54 [5.75-9.89], P < .001; ≥80 years: 7.57 [5.71-10.04], P < .001), female sex (1.10 [1.01-1.20], P = .047), nonwhite race/ethnicity (black: 1.94 [1.75-2.14], P < .001; Hispanic: 4.10 [3.74-4.48], P < .001; Asian: 3.16 [2.68-3.73], P < .001; Native American: 2.11 [1.45-3.08], P < .001), lower household income (quartile 2: 1.19 [1.07-1.32], P < .001), being insured with Medicare (1.56 [1.41-1.74], P < .001) or Medicaid (1.55 [1.39-1.73], P < .001), number of chronic conditions (2-5: 2.36 [2.10-2.65], P < .001; ≥6: 1.47 [1.29-1.69], P < .001), hospital location in a metropolitan area (not metropolitan or micropolitan: 0.60 [0.49-0.72], P < .001), and summer season (1.12 [1.02-1.23], P = .02) were all associated with hospitalization for pemphigus. The total inflation-adjusted cost of care for patients with a primary inpatient diagnosis of pemphigus was $74 466 305, with a mean (SD) annual cost of $14 520.93 ($913.22). The inflation-adjusted cost of care for patients with a primary diagnosis of pemphigus increased significantly from 2002 to 2012 (analysis of variance, P < .001). In particular, length of stay was higher in racial/ethnic minorities compared with whites (survey linear regression, log β [95% CI]: black: 0.076 [0.075-0.076]; Hispanic: 0.021 [0.021-0.022]; Asian: 0.037 [0.036-0.039]; Native American: 0.010 [0.0076-0.013]), lower quartile household income (quartile 1: 0.024 [0.023-0.024]; quartile 2: 0.0029 [0.0022-0.0035]), and those without private insurance (Medicare: 0.12 [0.12-0.12]; Medicaid: 0.082 [0.081-0.083]; no charge: 0.051 [0.047-0.055]).

CONCLUSIONS AND RELEVANCE

There is a significant inpatient burden for pemphigus in the United States. Moreover, there appear to be racial/ethnic and health care disparities with respect to pemphigus, such that poor, nonwhite, and/or uninsured or underinsured patients have higher odds of hospitalization.