Long-term hospital costs after transient ischemic attack (TIA) and stroke are considerable, but they are mainly incurred during the first year after the event. A recent U.K. study published in the November issue of Stroke also found that event severity and experiencing subsequent stroke and coronary events after the index event accounted for much of the increase in costs.
Although numerous studies have been published assessing the hospital care costs of stroke using patient-level data, few studies have evaluated costs for longer than one year after stroke onset, with an almost complete lack of long-term hospital cost data for TIA, according to the study authors.
They suggested that population-based studies with full case ascertainment (i.e., including minor events not admitted to the hospital and strokes resulting in death before, or soon after, hospital admission) are ideally required to determine the level and predictors of resource use and costs after TIA and stroke. Therefore, Ramon Luengo-Fernandez, DPhil, from the Health Economics Research Center in the department of public health at the University of Oxford in Oxford, England, and colleagues studied hospital care costs during the five years after any first incident or recurrent TIA or stroke in a population-based study.
The U.K. population-based cohort study (Oxford Vascular Study) recruited more than 91,000 patients from 2002 to 2007 from nine general practices across Oxfordshire in England. This analysis was based on follow-up until 2010. The researchers obtained hospital resource usage from patient hospital records and valued using 2008/2009 unit costs. Because not all patients had full five-year follow-up, they used nonparametric censoring techniques. In fact, the authors noted this as a limitation of their study, as 33 percent and 22 percent of TIA and stroke patients, respectively, did not yet have full five-year follow-up.
Among the 485 TIA and 729 stroke patients included in this study, the mean censor-adjusted five-year hospital costs after index stroke were $25,741, with costs varying considerably by severity: $21,134 after minor stroke; $33,119 after moderate stroke; and $28,552 after severe stroke. For the 239 surviving stroke patients who had reached final follow-up, the researchers reported that the mean costs were $24,383, with more than half of costs ($12,972) being incurred in the first year after the event.
An “important difference identified between the multivariate analyses of one- and five-year costs was that at one year after the index event, the only predictors of costs were clinical in nature; however, at five years, age and social history (including education levels, marital status, and place of residence) were all found to be predictors of hospital care costs,” Luengo-Fernandez et al wrote.
After index TIA, the mean censor-adjusted five-year costs were $18,091. “A multivariate analysis showed that event severity, recurrent stroke and coronary events after the index event were independent predictors of five-year costs,” the study authors wrote. “Differences by stroke subtype were mostly explained by stroke severity and subsequent events.”
As another limitation, the study omitted other relevant healthcare costs such as those relating to primary care visits or community care, as well as the costs of long-term institutionalization in either nursing or residential home care.
Finally, in terms of generalizing these findings to other countries, Luengo-Fernandez and colleagues noted that these “overall costs are only applicable to the United Kingdom and possibly to similar healthcare systems in which a high proportion of patients with TIA and minor stroke are investigated and treated in the outpatient setting. Our predictors of cost, however, are more likely to be generalizable to other healthcare settings.”