Emergency Department Utilization by HIV-Infected South Carolina Residents, 1996-2015

This study aimed to define the demographic characteristics of HIV-infected SC residents who made ED visits since cART was widely introduced in 1996. This population-based study examined a twenty-year period from 1996-2015. Our investigation revealed many significant findings. The number of ED visits made annually by HIV-infected SC residents has increased over time. The rate of increase is greater than that of the general population and therefore cannot be attributed to population growth alone. Previously published studies have suggested similar trends nationwide [4,8,9]. The reasons for this finding are not known. Prior studies have suggested that HIV-infected patients that visit EDs’ have a higher admission rate and therefore may present in worse condition than their uninfected counterparts [4,7]. They are also more likely to use the ED for low urgency visits [6]. Poor access to preventative services, greater incidence of comorbidities, substance abuse, low socioeconomic status and lack of insurance may preferentially direct HIV-infected patients to use ED services more commonly than uninfected patients [6,10-12].

Males represent 49% of the total state population but comprise the majority (71%) of HIV infected residents [13]. Males also consistently make the majority of ED visits in this state, however, women have been shown to comprise a growing percentage of annual ED visits over time. This is contrasted by a 34% decrease in newly diagnosed HIV cases in women over the past ten years [13]. Prior authors have suggested HIV-infected women demonstrate increased health care utilization and are more likely to use the ED than their male counterparts [9,14-16]. This, paired with inadequate primary care engagement, may be contributing factors to this discrepancy [17,18]. 

African-Americans are disproportionately affected by HIV in the state of SC. They comprise 28% of the total state population but represent 69% of the total HIV cases in this state [19,13]. The majority of ED visits were made by African-Americans, reflecting high disease prevalence in this group. Unfortunately, an increasing percentage of annual ED visits are made by African-Americans or other minority groups. Racial disparities in care exist which may increase the need for minorities to utilize EDs to meet their health care needs [20,21]. Other variables that have been associated with higher ED utilization that are found commonly in minority groups include poverty, lack of insurance, cost barriers, poor access to medical care and inadequate testing [19,22-24].

The HIV population in SC is aging. HIV-infected residents age 50 and older represent 46.7% of the total infected patients compared to 37% of the total state population [13]. While the majority of ED visits from 1996-2015 were made by the 18-44 year old age group, the greatest increase in ED visits occurred in the 45-64 year old and 65 years and older age groups. This trend likely reflects the changing demographic characteristics of our state’s HIV population. In addition, the aging HIV population in our state is realizing an increase in age-related conditions that require additional medical care and services which likely contributes to ED utilization [25]. The only age group to realize a decrease in ED utilization over time was the 0-17 year old age group. This reflects the continued decrease in HIV incidence documented in this age group.

Finally, the majority (62.5%) of counties that were listed in the top third percentile for total annual ED visits rates from 1996-2015 are considered rural. Rural residents in the US face many health issues including physician or provider work shortages, a widening gap in life expectancy and a wave of hospital closures [26]. Rural residents tend to be less healthy than their urban counterparts in part because of poor lifestyle choices [27]. Medicaid covers a larger percentage of rural residents compared to urban dwellers and therefore inadequate insurance coverage and the lack of Medicaid expansion in SC may also be adversely affecting rural-based, HIV-infected residents’ access to preventative care [28]. Rural residents are more likely to have a low socioeconomic status and this has been shown to be associated with greater ED use for conditions that can be managed in the outpatient setting [12]. Rural counties are also less likely to receive HIV preventative services which are likely to unfavorably influence ED utilization [29].

Our study has several limitations. The uniform billing database does not contain ED visits made on behalf of HIV-infected South Carolina residents in other states. In addition the database does not include clinical information i.e., CD4 counts, use of cART, or whether they are currently in care. Despite the introduction of cART, SC HIV-infected residents make ED visits at a higher rate than the general population. Certain demographic groups appear to be disproportionately represented in the ED setting. By targeting these high utilizer groups, the state may begin to better allocate resources and prevent the unnecessary and costly use of EDs in South Carolina.