摘要：Objectives. We assessed the relationship between individual characteristics and receipt of oseltamivir (Tamiflu) in the United States during the H1N1 pandemic and other flu seasons. Methods. In a cohort of individuals enrolled in pharmacy benefit plans, we used a multivariate logistic regression model to measure associations between subscriber characteristics and filling a prescription for oseltamivir during 3 flu seasons (October 2006–May 2007, October 2007–May 2008, and October 2008–May 2010). In 19 states with county-level influenza rates reported, we controlled for disease burden. Results. Approximately 56 million subscribers throughout the United States were included in 1 or more study periods. During pandemic flu, beneficiaries in the highest income category had 97% greater odds of receiving oseltamivir than those in the lowest category ( P < .001). After we controlled for disease burden, subscribers in the 2 highest income categories had 2.18 and 1.72 times the odds of receiving oseltamivir compared with those in the lowest category ( P < .001 for both). Conclusions. Income was a stronger predictor of oseltamivir receipt than prevalence of influenza. These findings corroborate concerns about equity of treatment in pandemics, and they call for improved approaches to distributing potentially life-saving treatments. Influenza outbreaks are common and cause substantial morbidity and mortality. 1 Although vaccination represents the primary strategy for the prevention of influenza, antiviral therapies including oseltamivir (Tamiflu) can be used to treat the disease and serve as prophylaxis when initiated shortly after exposure. 2–4 In a pandemic, it takes up to 6 months to create a novel vaccine; thus, at the beginning of a major outbreak, antiviral medications are likely to be the only countermeasure available. 5,6 In the 2009 H1N1 pandemic, early oseltamivir treatment of hospital patients successfully reduced deaths and admissions to critical care units. 7 Therefore, the effective and equitable allocation of antivirals, particularly if they are scarce, is a central public health concern and an important measure of the ability of the public health system to launch a robust response. Low-income populations are at greater risk in an influenza pandemic. Because of crowded living conditions, they may be more likely to be exposed to the disease. They also are less likely to receive timely and effective treatment after disease has developed. 5,8 Evidence from the 1918 influenza pandemic demonstrates that low-income populations experienced greater morbidity and mortality. 9 Evidence emerging from the 2009 H1N1 pandemic also indicates that poverty was a risk factor for severe disease. 10 Too little is known about the ability of low-income populations to access timely treatment during outbreaks of influenza. Although an article from the United Kingdom showed that socioeconomic deprivation was associated with decreased likelihood of accessing antivirals during H1N1, 11 no studies in the United States have explored the relationship between individual characteristics and receipt of oseltamivir. The 2009 H1N1 pandemic turned out to be a relatively mild event that did not push the response system to its limits. 12 However, when H1N1 first emerged, there was substantial media attention and public health concern about its potential risks to human health and society. 10 In anticipation of shortages of antiviral medications, the Centers for Disease Control and Prevention (CDC) released guidance to ensure that antivirals were reserved for influenza patients with, or at risk for, severe disease. 4 Even though demand for antiviral medications was ultimately weaker than many predicted, the majority of communities still witnessed shortages, especially of the pediatric formulation. 13 The large volume of flu cases in the winter of 2012–2013 highlights the ongoing need for careful evaluation of how influenza is managed across the country. We aimed to assess individual-level predictors of oseltamivir receipt, with a specific focus on the equitability of care. This analysis is key to understanding whether CDC recommendations (e.g., treat children, those with severe disease, and those with comorbidities) were followed by clinicians and whether communication and distribution strategies achieved equitable allocation.
