Emotional Distress, Barriers to Care, and Health-Related Quality of Life in Sickle Cell Disease
There have not been previous reports of symptoms of emotional distress in SCD using the PHQ-9 and GAD-7, but both measures have been used widely for depression and anxiety screening, including with African-American populations. We selected these over other measures for their brevity, free availability, and psychometric properties. Our prevalence of moderate to severe depression and anxiety symptoms in the present study was similar to what has been found using other tools [2–8]. The PHQ-9 and GAD-7 also provide ratings of symptom interference on daily functioning, and we found that these ratings were associated with impaired physical and mental HRQL. Given that there generally are limited mental health resources in the communities where individuals with SCD reside and are treated, ratings of emotional distress and HRQL can be taken together to stratify those patients with the most immediate need for interventions. Further, screening can be used for early detection with the goal to intervene and prevent the progression of symptoms of emotional distress to long-term, disabling mental health disorders [54]. There is a need for innovative and cost-effective strategies for assessment and treatment of mental health symptoms and disorders for patients with SCD. One model for evidence-based practice in the management of emotional distress for patients with in SCD is the collaborative care model.
The collaborative care model integrates physical and mental health care in the patient-centered medical home and focuses on treating the whole person and family [55]. In this model, a care management staff (eg, nurse, social worker, psychologist) is integrated with the primary care team. The care management staff, in consultation with a psychiatrist, provides evidence-based care coordination, brief behavioral interventions, and support for other treatments, including medications. The effectiveness of collaborative care programs has been demonstrated for ethnic minority and safety net populations such as the SCD population, which is disproportionately low-income and on public insurance [56, 57]. Future research with SCD populations should investigate such interventions as the collaborative care model that addresses both emotional distress and barriers to care.
Limitations
Our results need to be interpreted with caution given the small sample size and the potential bias introduced by non-random sampling. In addition, as our patients are from an urban setting, findings might not generalize to rural populations. This study was cross sectional so no inferences can be made with regard to causality and temporal relations between anxiety symptoms, barriers to care, and HRQL. Our strategy for measuring total clinical complications and barriers to care conserved power but it was not possible to evaluate if specific complications or barriers may have exerted a greater impact on HRQL compared with others. Similarly, other studies have examined specific domains of HRQL, while we limited our analysis to the Physical and Mental Component Summary scores. The utilization questionnaire was designed to assess only lifetime complications, not complications more proximal to the HRQL ratings.
Patient-reported outcomes, now widely accepted as outcome measures, elicit patients’ descriptions of the impact of their condition on their day-to-day lives [34, 58–60]. However, measures of mental health symptoms and HRQL may be subject to recall bias, measurement error, and confounding [61,62]. Nevertheless, a range of studies support the idea that mental health symptoms and HRQL are distinct constructs, and that patients with physical and mental health symptoms are vulnerable to lower ratings of HRQL [63,64]. Disease-modifying therapies such as hydroxyurea can contribute to improved ratings of HRQL [44,65], but we were not able to evaluate the contribution of hydroxyurea to HRQL as it appears to have been underutilized in our sample.
Conclusion
We evaluated emotional distress and other variables in the context of a biobehavioral model of HRQL outcomes for adults with SCD. Integrating the patient's perspective of the impact of the disease and its treatment with assessment of clinical indications is critical to implementing and evaluating effective therapies [25]. However, there are conceptual challenges in determining what actually contributes to HRQL from the patient’s perspective in the context of genetic disorders such as SCD [50]. Our findings highlight the importance of incorporating comprehensive psychosocial screening in order to support optimal HRQL in SCD. Providers may be reluctant to include such screening if, as is often the case, mental health services are difficult to access. Models such as the collaborative care model, which include mental health interventions within the sickle cell center or primary care provider’s office, should be implented. Barriers to care and HRQL should also be routinely evaluated for patients with SCD. Use of disease-specific tools, such as the Adult Sickle Cell Quality of Life measurement system [66], may increase the specificity needed to detect differences within adults with SCD and improvements related to interventions, whether medical or psychosocial. Contributors to HRQL in SCD go beyond clinical manifestations to include psychological and social factors, as well as provider and health system variables. Research conducted within the framework of a comprehensive conceptual model of broad clinical and life effects associated with SCD can inform clinical applications that ultimately enhance HRQL for patients with SCD.
Acknowledgment: The authors wish to thank San Keller, PhD, for her helpful comments on a previous version of this manuscript.
Corresponding author: Marsha J. Treadwell, PhD, Hematology/Oncology Dept., UCSF Benioff Children’s Hospital Oakland, 747 52nd St., Oakland, CA 94609, mtreadwell@mail.cho.org.
Funding/support: This research was conducted as part of the National Initiative for Children’s Healthcare Quality (NICHQ) Working to Improve Sickle Cell Healthcare (WISCH) project. Further support came from a grant from the Health Resources and Services Administration (HRSA) Sickle Cell Disease Treatment Demonstration Project Grant No. U1EMC16492 and from the National Institutes of Health (NIH) Clinical and Translational Science Award UL1 RR024131. The views expressed in this publication do not necessarily reflect the views of WISCH, NICHQ, HRSA or NIH.
Financial disclosures: None.
Author contributions: conception and design, MJT; analysis and interpretation of data, MJT, GG; drafting of article, MJT, GG; critical revision of the article, MJT, KK, FB; statistical expertise, GG; obtaining of funding, MJT; administrative or technical support, KK, FB; collection and assembly of data, KK, FB.
