In the United States, an estimated 1.2 million persons are living with HIV infection1 and approximately 44,000 persons were diagnosed with HIV infection in 2014.2 Improvements across the HIV care continuum are needed to achieve the goals of the National HIV/AIDS Strategy to maximize individual health benefits and to reduce new infections.3 The percentage of persons who are receiving HIV medical care but not prescribed antiretroviral therapy (ART) declined from an estimated 11% in 2009 to 6% in 2013, largely as a result of efforts to improve engagement in care for persons living with HIV (PLHIV) and to promote early ART use.4–6 Since 2012, the Department of Health and Human Services (DHHS) has recommended ART for all persons diagnosed with HIV infection, barring medical contraindications to treatment, comorbid conditions that affect patients' readiness to start a regimen that requires sustained adherence, and patient unwillingness to begin treatment. Based on the results of the START7 and TEMPRANO8 trials, both DHHS9 and the World Health Organization10 now recommend initiating ART soon after diagnosis of HIV infection regardless of CD4 cell (CD4) count. However, even if all providers adopted this standard of care, many would defer treating some patients because of contraindications or barriers to treatment. A 2009 study examining reasons that providers deferred prescribing ART for otherwise eligible patients cited concerns about patient adherence because of medical or social factors, concerns about structural barriers, and lack of acceptance by patients.11 In light of the expansion of treatment recommendations since then, reexamining these barriers may be useful for developing timely methods to help maximize use of ART.
We surveyed a probability sample of US HIV care providers to elicit information about practices related to initiation and deferral of ART. Specifically, we assessed the percentage of HIV care providers who would initiate ART regardless of CD4 count for patients with no medical contraindications or barriers to treatment, how these providers differed from those who would initiate ART based on CD4 count thresholds, and the percentage of all providers who deferred prescribing ART for any reason and their reasons for deferral.
Sample Design and Data Collection
The Medical Monitoring Project (MMP) is an ongoing HIV surveillance system that from 2009 to 2014 used a 3-stage probability sampling design to assess the clinical and behavioral characteristics of adult PLHIV who are receiving outpatient medical care for HIV in the United States.5,12 Data describing provider characteristics and practices were obtained from the 2013 to 2014 MMP Provider Survey, using a national probability sample of HIV care providers. Briefly, 16 states and 1 territory were selected using probability proportionate to size sampling at the first stage, with size based on estimates of the number of AIDS cases in 2002. All sampled areas agreed to participate. At the second stage, 622 facilities providing HIV care within these areas were sampled using probability proportionate to size based on the number of persons receiving care for HIV infection; of these, 505 agreed to participate (81% participation rate). A list of all physicians, physician assistants, and nurse practitioners who between January 1 and April 30, 2012 had completed their training and provided HIV care (defined as ordering CD4 counts or HIV viral load tests or prescribing antiretroviral medications) was obtained from each participating facility, resulting in a total of 2208 HIV care providers. All these providers were invited to participate in the survey.
Providers were recruited with a modified version of Dillman Tailored Design.13 We mailed recruitment packets, including instructions for completing the self-administered survey via paper or a web-based response system, and a $20 cash incentive to all providers in selected facilities between June 2013 and January 2014. In all, 2023 (91.7%) of 2208 providers were determined to be eligible, and 1234 of these eligible providers returned surveys (American Association of Public Opinion Research, Response Rate 3 adjusted provider response rate14 64.0%) from 391 HIV care facilities. The data were weighted based on probability of selection, and adjustments were made to the probability weights based on factors associated with nonresponse. The sample design and weighting methods allow inference from estimates to all HIV care providers at outpatient HIV health care facilities in the United States between January 1 and April 30, 2012. See Supplemental Digital Content, http://links.lww.com/QAI/A962, for detailed information on sampling methods and response rate calculation.
Variables Used in the Analysis
The survey instrument consisted of 61 questions and took about 30 minutes to complete on average. Domains included professional qualifications, experience, demographics, prescribing practices, and practice characteristics. Providers were asked: “Among patients for whom there were no barriers or contraindications, when would you first prescribe ART?” Response options were: <200, <350, <500 cells per cubic millimeter, or treat regardless of CD4 count. We constructed a 2-level variable for threshold to initiate ART: “Treat regardless of CD4 count” or “<200, <350, or <500 cells per cubic millimeter” to indicate adoption vs. nonadoption of treatment recommendations. Providers were categorized according to the percentage of patients for whom they deferred prescribing ART for any reason: none, 1%–10%, or >10%. Providers were offered reasons for deferring and were asked to indicate the percentage of patients (0%, 1%–10%, 11%–25%, 26%–50%, >50%) for whom each applied as a reason to defer prescribing ART. Reasons for deferral included patient refusal or unwillingness to commit to treatment, patient inability to pay for medications or coverage delays, provider concerns about nonadherence because of a medical problem (eg, substance abuse, mental health, other illness) or social problem (eg, homelessness, incarceration, or migrancy), provider inability to construct an effective and acceptable regimen, and provider not agreeing with recommendations to treat regardless of CD4 count. For analysis, responses were collapsed to 2 categories: ≤50% vs. >50% of patients. Physicians (MDs and DOs) who were board certified in infectious diseases (ID) were classified as ID physicians regardless of any additional board certifications. Providers were classified by HIV Medicine Association15 or American Academy of HIV Medicine (AAHIVM)16 HIV specialist status, whether they provided primary care (for definition, see online methods, Supplemental Digital Content, http://links.lww.com/QAI/A962), and by HIV patient caseload (≤20, 21–50, 51–200, or >200 patients). Respondents were also asked to indicate on a 5-point Likert scale how strongly they agreed that various prescription drug plans were sufficient to meet their patients' HIV treatment needs. For analysis, these responses were collapsed to 2 categories: somewhat or strongly agree vs. neither agree nor disagree, somewhat disagree, or strongly disagree. Using data from a previous MMP facility survey, we determined whether the facilities where providers worked received Ryan White HIV/AIDS Program (RWHAP)17 funding and if they were or were not private practices. Providers were also asked which on-site support services were available to patients at the facilities.
We computed frequencies and weighted percentages and their corresponding 95% confidence intervals (CI) describing the target provider population, facilities where they worked, and providers' ART-related clinical practices. Rao-Scott χ2 tests were used to assess associations between selected variables and the probability of providers initiating ART regardless of CD4 count. In a multivariate logistic regression model, we included provider and facility characteristics that were conceptually and statistically associated (P ≤ 0.05) with the outcome of initiating ART regardless of CD4 count. All estimates incorporated the adjusted survey weights. Variance estimates were computed using Taylor Series Linearization to reflect the complex features of the MMP provider survey sample, such as cluster sampling of facilities. We used SAS/STAT (Version 9.3) and SUDAAN (Version 11) procedures for the analysis of complex sample survey data. We considered estimates with a coefficient of variation greater than 0.3 unreliable.
MMP, as a public health surveillance activity, was determined to be nonresearch in accordance with the federal human subjects protection regulations at 45 Code of Federal Regulations 46.101c and 46.102d and the Guidelines for Defining Public Health Research and Public Health Nonresearch of the Centers for Disease Control and Prevention.18,19 Participating states or territories and facilities obtained local Institutional Review Board approval to conduct MMP, if required locally.
We estimate that in 2012, there were 8257 (CI: 6902 to 9611) HIV care providers in the United States. An estimated 44.5% of providers were ID physicians, 30.0% other board-certified physicians, 15.2% nurse practitioners, 5.4% physician assistants, and 4.8% non–board-certified physicians (Table 1). In all, 57.8% of providers met HIV Medicine Association or AAHIVM specialist criteria and 83.1% provided primary care. HIV caseloads of ≤20, 21–50, 51–200, and >200 patients were reported by 15.1%, 19.6%, 39.0%, and 26.3% of providers, respectively. Among all providers, 25.3% reported comanaging their patients by receiving expert assistance as did 52.2% of providers with caseloads of ≤20 patients. Most providers agreed or strongly agreed that the following prescription programs met their patients' treatment needs: AIDS Drug Assistance Program (ADAP), 91.1%; Medicare, 72.8%; Medicaid, 81.3%; commercial insurance, 71.3%; and pharmaceutical industry–sponsored patient assistance programs, 59.2%. An estimated 47.5% of providers cared for patients at RWHAP-funded facilities and 41.9% worked in private practices.
Initiation of ART Regardless of CD4 Count
An estimated 71.2% of providers reported initiating ART regardless of CD4 count, whereas 1.2%, 8.7%, and 18.9% of providers initiated ART for patients with CD4 counts of <200, <350, and <500 cells per cubic millimeter, respectively (Table 2). In bivariate and multivariable analyses, providers with patient caseloads of ≤20 patients vs. >200 patients [47.3%, CI: 34.3 to 60.3, vs. 79.3%, CI: 72.6 to 86.1; adjusted prevalence ratio (aPR) 0.69, CI: 0.47 to 1.02, P = 0.03] as were providers at non–RWHAP-funded facilities (61.7%, CI: 50.6 to 72.9, vs. 80.4%, CI: 74.1 to 86.6; aPR 0.85, CI: 0.74 to 0.98, P = 0.02) and providers who reported that pharmaceutical companies' patient assistance programs did not provide sufficient medication to meet their patients' needs (62.0%, CI: 51.2 to 72.7, vs. 78.0%, CI: 71.6 to 84.3; aPR 0.80, CI: 0.65 to 0.98, P = 0.02) (Table 3) were less likely to initiate ART regardless of CD4 count. None of the other variables assessed were associated with initiating ART regardless of CD4 count.
Deferral of ART Prescription for Any Reason
Among all providers, 17.0% reported that they never deferred prescribing ART for any reason, 69.6% deferred for 1%–10% of patients, and 13.3% deferred for more than 10% (Table 2). Among providers who had deferred prescribing ART, 59.4% cited patient refusal as a reason in >50% of cases when they deferred; similarly, 31.1% reported adherence concerns because of substance abuse or mental health problems; 21.4% reported adherence concerns because of social problems, such as homelessness; 10.5% cited inability to pay for medications; and 3.2% said that disagreeing with recommendations to initiate treatment regardless of CD4 count was a reason for deferring in >50% of cases. An estimated 54.2% of providers reported practicing at a facility with on-site adherence counseling, 45.1% at a facility with mental health services, 23.5% at a facility with substance abuse treatment, and 50.8% at a facility with HIV case management services.
We estimated that between June 2013 and January 2014, 71% of HIV care providers would initiate ART regardless of CD4 count for PLHIV with no medical contraindications or barriers. Providers who had HIV caseloads of ≤20 patients, worked at non–RWHAP-funded facilities, or found that pharmaceutical companies' patient assistance programs were unable to provide sufficient medication to meet their patients' needs were less likely to have adopted this standard of care for initiating ART. More than 5 in 6 of all providers reported that they deferred prescribing ART for some patients, including 13% who deferred for >10%. The most frequently cited reasons for deferral were patient refusal and concerns about nonadherence because of substance abuse or mental illness or social problems, such as homelessness.
As evidence of the clinical7,8,20,21 and public health22,23 benefits of universal ART has accumulated and concerns about tolerability, toxicity, and durability have waned,24 recommendations have broadened to include offering treatment to all persons diagnosed with HIV9,10 and the strength of the recommendation for earlier treatment has been increased.9,10 In an earlier study, 68% of providers in the Bronx, NY, and Washington, DC, who participated in the HIV Prevention Trials Network 065 study in 2010–201125 reported initiating ART regardless of CD4 count as did 69% of providers affiliated with the New England AIDS Education and Training Center during 201326 and 87% of ID physicians who were members of the Emerging Infections Network in 2014.27 Our study was the first to examine physicians, nurse practitioners, and physician assistants at different types of facilities throughout the country, representative of the diversity of US HIV care providers. We also assessed associations between ART initiation practices and a wide range of provider characteristics.
In all, 29% of providers used a CD4 count threshold in deciding whether to initiate ART for patients without contraindications or barriers to treatment. Identifying and understanding the needs of these providers may help reduce the 6% of patients not currently prescribed ART. Providers who cared for ≤20 patients (15% of all HIV care providers) were less likely than those with large caseloads to follow current recommendations. Other provider surveys have similarly observed that providers with smaller caseloads were less likely than those with larger caseloads to report adhering to antiretroviral prescribing guidelines.28–30 Though evidence suggests that expert consultation improves provider and patient outcomes,31 we found that half of providers with caseloads <20 patients managed their patients without the assistance of an HIV specialist. Pairing of providers who care for fewer than 20 patients with highly experienced providers is available through the AAHIVM Clinical Consult Program.32 Another resource for supporting low-volume providers is the AIDS Education and Training Center Program, the training arm of the RWHAP that provides a national network of HIV experts offering education, clinical consultation, and technical assistance.33 Low-volume providers can be identified by local health departments and offered opportunities for clinical training and support using antiretroviral prescription claims data34 and potentially also laboratory surveillance data.
Practicing in a non–RWHAP-funded facility was another independent predictor of providers using a CD4 count threshold in deciding when to initiate ART for patients without contraindications or barriers to treatment. Another analysis of MMP provider survey data observed that these providers were also less likely to report delivering recommended ART adherence support to patients than providers at RWHAP-funded facilities.35 These findings suggest a need to support non-RWHAP providers in addition to low-volume providers to adopt currently recommended ART prescribing practices.
Providers who reported that pharmaceutical industry–sponsored patient assistance programs provided sufficient medication to meet their patients' needs were more likely to initiate ART regardless of CD4 count for patients without contraindications or barriers to treatment. Providers may turn to patient assistance programs that use CD4 criteria to determine eligibility to fill gaps in coverage left by prescription drug plans, including ADAP. Notably, in 2015, RWHAP programs in 9 states required a CD4 count of 500 cells per cubic millimeter or less to qualify for ADAP.36
Although 29% of providers would not initiate ART for patients with a CD4 count above a particular threshold, only 3% of providers who ever defer prescribing ART reported that disagreeing with the recommendation to treat patients regardless of CD4 count, barring contraindications, or barriers to treatment was a reason in more than half of cases. Other reasons for deferring ART, which may be consistent with guidelines that recommend taking into account patients' readiness and willingness, were more common. A majority of providers cited patient refusal as a common reason to defer prescribing, and many identified concerns about treatment nonadherence because of either substance abuse or mental health problems (31%) or social problems, such as homelessness (21%). Similar findings were reported in surveys of HIV care providers in 2009,11 2010–2011,37 and 2013.25
Patient unwillingness to accept ART is the single most commonly reported barrier to prescribing ART. However, when patients were interviewed for MMP, the most common self-reported reason for never having taken ART (80%) or discontinuing ART (35%) was that the doctor advised delaying or stopping treatment.5 A recent study in which patient–provider dyads were interviewed about reasons for lack of ART usage may help explain this apparent inconsistency. Christopoulos et al38 found that many patients were not taking ART because they had internalized messages from their providers over time that their health was stable and that ART was not warranted at the time. Providers practicing patient-centered care often muted the offer of ART, at times unintentionally. Patients reported that providers had not strongly advised them to take ART, and many said that such a clear recommendation would be necessary to initiate ART. Future treatment and prevention guidelines should recommend that providers strongly advise all patients to initiate ART barring medical contraindications or barriers to treatment.
Concern about the effect of substance abuse and mental health disorders on medication adherence was the second most common reason why providers deferred prescribing ART. The link between these conditions has been established,39–41 but the level of impact is not immutable. Interventions to treat clinical depression and simultaneously support adherence with cognitive and behavioral skills can improve both depression and adherence outcomes.41 Among patients with opioid dependence, methadone and buprenorphine maintenance can improve medication adherence, and directly administered ART has been associated with improved clinical outcomes among substance abusers.42
Among providers who reported that they deferred prescribing ART, 1 in 5 cited social problems, such as homelessness, as a factor in most instances. However, evidence also suggests that providers may have limited ability to predict which patients will be able to adhere to treatment.43 Even though homeless patients, in general, may be at greater risk of ART nonadherence,44 many can achieve levels of adherence comparable with housed populations45 and benefit from ART even if adherence is suboptimal.46
Federal guidelines state the following: “ART reduces morbidity and mortality even in patients with relatively poor adherence and established drug resistance. Thus, mental illness, substance abuse, and psychosocial challenges are not reasons to withhold ART from a patient. Rather, these issues indicate the need for additional interventions to support adherence….”9(pE5) A systematic review has identified 10 evidence-based interventions that can promote ART adherence.47 However, only half of the providers reported the availability of on-site HIV case management, adherence support services, or mental health services and one-quarter practiced in a facility with on-site substance abuse treatment. Increased access to these services, all of which are more readily available at RWHAP-funded facilities,48 would address many of the reasons that providers defer prescribing ART.
Our study was subject to limitations. The survey was conducted before the strength of the DHHS recommendation to offer treatment regardless of CD4 was changed in 2015 from moderate to strong.9 The percentage of providers who follow the recommendation may be higher today. ART prescription may also have increased if upward trends have continued since 2013.6 Second, estimates were based on self-report and may have been subject to measurement error because of socially desirable responding, which could, eg, increase the percentage of providers who reported that they would initiate ART regardless of CD4 count and decrease the percentage who reported that disagreeing with this recommendation is a reason in more than half of cases when they defer. Finally, because MMP provider and patient data are not linked, we were unable to assess possible confounding of associations between provider characteristics and reported prescribing practices by patient sociodemographic characteristics.
In conclusion, factors limiting universal ART prescription include incomplete adoption of recommendations to initiate ART regardless of CD4 count for patients without contraindications or barriers to treatment, patient refusal, and provider concerns about nonadherence because of medical and social problems. Supporting low-volume providers and providers at non–RWHAP-funded facilities in adopting standard of care practices for ART initiation and addressing other barriers to treatment may help reduce this gap in the HIV care continuum.
The authors would like to thank the participating Medical Monitoring Project (MMP) providers, facilities, project areas, and Provider and Community Advisory Board members. They also acknowledge the contributions of the Clinical Outcomes Team, the Behavioral and Clinical Surveillance Branch, and other members of the Division of HIV/AIDS Prevention at Centers for Disease Control and Prevention and the MMP 2013 Study Group Members: http://www.cdc.gov/hiv/statistics/systems/mmp/resources.html#StudyGroupMembers. The authors also wish to thank the Altarum Institute data collection team.
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