Do Patient-Reported Outcomes Correlate with Clinical Outcomes Following Surgery?

Advances in Surgery j (2017) j–j

ADVANCES IN SURGERY Do Patient-Reported Outcomes Correlate with Clinical Outcomes Following Surgery? Jennifer F. Waljee, MD, MS, Justin B. Dimick, MD, MPH* Department of Surgery, Center for Health Outcomes and Policy, University of Michigan, 1500 East Medical Center Drive, Ann Arbor, MI 48109, USA

Keywords 

Patient-reported outcomes  Quality  Surgery  Quality of life

Key points 

Patient-reported outcomes describe aspects of health that are reported directly from patients and encompass important elements of disability and function, including mobility, pain, and mood.



Patient-reported outcomes are distinct from clinical outcomes and patient experience and offer a unique perspective of clinical effectiveness of treatment options.



Going forward, patient-reported outcomes will likely be increasingly leveraged for the purpose of quality assessment and improvement across surgical and medical conditions.

INTRODUCTION More than 45 million Americans undergo surgery each year in the United States, with expenditures exceeding $500 billion and accounting for approximately 40% of national health care spending [1–3]. Currently, measures of treatment effectiveness and quality for surgical conditions are primarily centered on clinical outcomes, such as complication rates, mortality, and readmission. Clinical outcomes are well suited for this purpose because they can be easily obtained from administrative and clinical records and have Funding Source: This work was supported by a Mentored Clinical Investigator Award (5K08 HS23313-04) to Dr J.F. Waljee through the Agency for Healthcare Research and Quality (1K08HS023313-01).

*Corresponding author. 1500 East Medical Center Drive, 2131 Taubman Center, Ann Arbor, MI 48109. E-mail address: [email protected] http://dx.doi.org/10.1016/j.yasu.2017.03.011 0065-3411/17/ª 2017 Elsevier Inc. All rights reserved.

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high face validity for surgeons in practice. Because clinical outcomes are discrete events, they can be quantified and categorized with ease. Furthermore, there is empirical evidence that tracking clinical outcomes improves care [4]. Clinical outcomes have been widely applied to quality-improvement strategies, such as selective referral of patients to high-performance centers, incentives for compliance with accepted standards of care, and clinical registries that systematically track and report outcomes [4–9]. Although postoperative clinical outcomes can reflect many aspects of perioperative safety and technical performance, they do not inherently capture the patient perspective. In this review, the authors explore the scope of patient-reported outcomes (PROs) and consider their potential role as metrics to define treatment effectiveness and health care quality. WHAT ARE PATIENT-REPORTED OUTCOMES? PROs describe aspects of health status that are reported directly from patients, without interpretation by others [10–14] (Table 1). Common examples of PROs include symptoms, quality of life, disability, mobility, and pain. Instruments to measure PROs can be broadly classified as generic and condition specific (Table 2). Generic PRO measures capture well-being along dimensions that are common across conditions, such as physical function, social function, pain, and depression or anxiety. Instruments may provide a single value for a given health state or assess health status state along multiple dimensions. Generic instruments are advantageous in that PROs can be compared across conditions and interventions and may detect unexpected treatment effects [15,16]. However, generic instruments may also lack relevant detail regarding a given condition and are often insensitive to clinical change over time. Examples of generic measures that assess PROs include the EuroQol Five Dimensions Questionnaire (EQ-5D), Health Utilities Index,

Table 1 Clinical outcomes versus patient-reported outcomes

Definition Example Advantages

Disadvantages

Clinical outcomes

PROs

Occurrence of specific clinical events 30-d procedural mortality Outcomes easily quantified Available in clinical and administrative data Comparable across providers Do not capture all aspects of recovery Infrequent for common, safe procedures Risk differences difficult to interpret

Self-reported health status or experience Health-related quality of life Outcomes obtained directly from patients Germane to patient experiences Reflect long-term effects Labor intensive data collection Validity and reliability vary by instrument Difficult to obtain if communication barriers

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Table 2 Generic versus condition specific instruments Generic Instruments

Condition-Specific Instruments

Example

PROMIS, SF-36

Advantages

Can compare treatments across groups Can compare with healthy individuals Can detect unexpected effects Lack relevant detail

Michigan Hand Outcomes Questionnaire Clinically relevant

Disadvantages

Limited responsiveness to change

Responsive to change over time Sensitive to outcomes of interest Difficult to compare with general population Cannot compare across diseases May not detect unforeseen effects or symptoms

Abbreviations: PROMIS, Patient-Reported Outcomes Measurement Information System; SF-36, 36-Item Short Form Health Survey.

the 36-Item Short Form Health Survey (and derivatives), and the PatientReported Outcomes Measurement Information System [17–21]. In contrast, condition-specific measures capture aspects of health status that are related to a specific disease or disability. Condition-specific PRO measures are appealing in that they often detect more granular changes in health or functional status. However, these measures are difficult to compare across conditions and may not capture unforeseen treatment effects. Examples include measures that capture hand function (Michigan Hand Outcomes Questionnaire), orofacial appearance and functioning among children with cleft lip and palate (Cleft Evaluation Profile), and reconstructive outcomes following breast cancer (Breast Q) [22–25]. To date, no single instrument has been established as the gold standard to assess all aspects of patient-reported health status, and a combination of instruments are typically used in practice. PATIENT-REPORTED OUTCOMES VERSUS PATIENT-REPORTED EXPERIENCES Although both have gained considerable attention with the growing interest in patient-centered care, it is important to note that PROs are distinct from measures of patient experience. Patient experience describes elements of patient satisfaction around a clinical encounter and has been defined as ‘‘the sum of all interactions, shaped by an organization’s culture, that influence patient perceptions across the continuum of care.’’ [26] Aspects of experience often include accessibility of services, communication between patients and providers, and the environment (eg, noise levels) and can provide a unique perspective regarding processes of care and care delivery that differ from clinical and PROs [27]. For example, the Consumer Assessment of Healthcare Providers and Systems (CAHPS) program collects self-reported data regarding inpatient hospital care, such as provider communication and cleanliness [28]. Although,

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CAHPS scores have been shown to correlate with some measures of treatment effectiveness and safety, they often diverge from morbidity- and mortalityrelated measures and reflect an aspect of quality distinct from clinical and PROs [28–30]. PATIENT-REPORTED OUTCOMES AND TREATMENT EFFECTIVENESS Today, most common surgical procedures, such as joint replacement, spine surgery, carpal tunnel release, and hernia repair, are performed for symptoms, including pain, disability, mobility, and quality of life [31]. Therefore, PROs are essential to defining the clinical effectiveness of surgical care. PROs capture the benefits of surgery beyond survival and physiologic markers and are often the outcomes most important to patients and clinicians. Although practicing clinicians assess PROs each day when caring for patients (asking How are you doing? Is your pain improving? What can I do to help you?), formal consideration of PROs in the context of treatment effectiveness took hold in the 1970s and 1980s [32]. For example, Health Insurance Experiment examined the relationship between patient-reported health status and health behaviors and cost sharing across health care coverage in response to a growing national interest in measuring and improving the value of health care [33]. In addition, the Medical Outcomes Study was one of the first to examine the variation of PROs and the effect of provider-level factors on this variation and sought to systematically create practical and efficient methods to capture patient-reported health status [34]. Throughout the twenty-first century, the use of PROs to understand clinical effectiveness continued to gain traction. In 2006, the Food and Drug Administration (FDA) advocated for the use of PROs to be included in the labeling, development, evaluation, and regulation of medical devices, pharmaceuticals, and technology [10,35]. For example, symptoms and performance status are now often captured alongside traditional metrics, such as survival and tumor response, in clinical trials comparing the efficacy and clinical benefit of chemotherapeutic agents [36,37]. Moreover, the FDA has now advocated to standardize the measurement and interpretation of PROs in drug development and clinical research to enhance generalizability and transparency [38]. In this context, the inclusion of PROs alongside clinical outcomes has enhanced our ability to define treatment effectiveness. For example, many chemotherapeutic agents that are efficacious in slowing tumor growth are not well tolerated by patients, limiting their clinical application particularly for patients with advanced disease [39]. For surgical conditions, PROs may provide a better assessment of long-term outcomes. For example, for patients undergoing knee and hip arthroplasty, implant failure rates, including periprosthetic fracture, infection, implant dislocation, and surgical revision, are commonly used to define successful outcomes. By these standards, knee arthroplasty is quite successful, with excellent outcomes of greater than 80% [40,41]. However, knee arthroplasty is most commonly performed for degenerative osteoarthritis;

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evaluation of treatment outcomes based on long-term pain and mobility reveals more modest success rates of 60%, suggesting pain and disability persist even without implant failure. PROs may also be used as a prognostic indicator. For example, studies among patients with cancer demonstrate that patients who report higher baseline quality of life experience greater survival and quality of life outcomes independently predict both overall and disease-free survival after adjusting for other factors [42,43]. With respect to surgery, preoperative measures of patient-reported quality of life and frailty are correlated with the incidence of short-term postoperative complications and mortality across common surgical procedures [44,45]. PROs also predict long-term durability of outcomes. For example, higher preoperative scores that capture pain, depression, and anxiety indicate greater pain, poorer mobility, and the development of chronic narcotic dependence following knee and hip arthroplasty as well as hysterectomy [46– 50]. Therefore, considering PROs alongside clinical outcomes can provide a more comprehensive assessment of short- and long-term treatment effectiveness across conditions. PATIENT-REPORTED OUTCOMES AND QUALITY OF CARE Beyond treatment effectiveness, professional societies and large payers are keen to identify the most accurate measures of surgical performance in order to improve the safety and efficiency of surgical care. Clinical outcomes data, such as perioperative morbidity and mortality, are commonly used to discriminate the best and worst performing providers. Although patient perspectives have rarely been considered for this purpose, PROs could provide a comprehensive approach to quality, particularly for procedures with low perioperative risk but a substantial influence on long-term function, disability, and quality of life [51]. Furthermore, PROs align with health care initiatives that emphasize patient-centered care and are central to many reforms outlined in the Patient Protection and Affordable Care Act of 2010. Despite this appeal, collecting PROs is labor intensive and expensive. Moreover, physicians currently spend roughly 15 hours per week and $15.4 billion per year on quality measures [52]. Given these logistical and financial challenges, it is important to know if PROs add value to existing quality assessment and improvement strategies in order to use scarce resources most effectively. An ideal quality measure should demonstrate variability and provide unique and important information [53]. Recent studies suggest that PROs following surgery do vary across hospitals and surgeons and may provide an opportunity to distinguish clinical performance (Fig. 1) [54,55]. Since April 2009 in the United Kingdom, the National Health Service systematically captures PROs following elective surgical procedures, including knee and hip arthroplasty, varicose vein removal, and hernia repair, using multidimensional generic and condition-specific instruments [51,54,56,57]. In April 2014, the National Patient-Reported Outcome Measure Program (PROM) was extended to include the Best Practice Tariff, which effectively linked reimbursement to performance based on PROs. Scores for

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Fig. 1. Variation in patient-reported health-related quality of life (HRQOL) across hospitals following bariatric surgery. HALEX, Health and Activities Limitation Index; MBSC, Michigan Bariatric Surgical Collaborative. (From Waljee JF, Ghaferi A, Finks JF, et al. Variation in patientreported outcomes across hospitals following surgery. Medical Care 2015;53(11):960–6; with permission.)

each aspect of health status (eg, mobility or activities of daily functioning) are aggregated into a single index score and adjusted for preoperative risk by relating overall scores to a national average of case-mix control patients [54,57–60]. In the National PROM Program, PROs vary across providers and surgeon ranking is influenced by patient risk, procedure, selected PRO measure, and domain (eg, mobility, pain) [54,56,57,61]. Notably, however, scores are also influenced by missing items and nonresponse [62–64]. Additionally, recent evidence suggests that PROs demonstrate some overlap with clinical outcomes. For example, an analysis of both clinical outcomes and PROs drawn from the Michigan Bariatric Surgical Collaborative, a statewide consortium of hospitals performing bariatric surgery, examined the correlation between bariatric-specific and overall health-related quality of life, clinical complications, and postoperative weight loss [65]. In this cohort, most patients experienced substantial gains in both overall and condition-specific quality of life. However, long-term clinical outcomes, including weight loss and comorbidity resolution, were more strongly correlated with PROs, particularly bariatricspecific quality of life, compared with postoperative complications. These findings align with other studies that demonstrate that in-hospital complications do not necessarily predict decrements in long-term quality of life, and many patients report satisfaction and well-being despite the occurrence of more immediate

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perioperative complications [66–69]. In this context, PROs may be redundant with long-term clinical outcomes, particularly those specific to a given condition, such as weight loss following bariatric surgery. However, unexplained variation persists across broader measures of quality of life, including mobility, pain, and mood, suggesting these outcomes may reflect distinct aspects of care [70]. SUMMARY Wide variation in surgical care in the United States demands comprehensive and meaningful measures of treatment effectiveness and quality [7]. Major postoperative complications, such as renal failure requiring dialysis or myocardial infarction, remain prevalent and much more common than death following surgery [71–73]. Debilitating complications are correlated with longer hospital stays, loss of independence, and temporary or permanent residence in nursing facilities [74]. Moreover, considering outcomes from the patients’ perspective, the public health burden of surgery is likely to be even higher. PROs are distinct from clinical outcomes and represent a potential indicator of performance that can be targeted to improve quality of care. Future studies that examine the influence of measurement techniques, case mix, and disease characteristics on PROs will inform efforts to routinely and efficiently integrate these critical outcomes into existing strategies to capture treatment effectiveness and quality of care for surgical conditions. References [1] Russo A, Elixhauser A, Steiner C, et al. Hospital-based ambulatory surgery, 2007. Healthcare Cost and Utilization Project (HCUP). Rockville (MD): Agency for Healthcare Research and Quality; 2010. [2] Cullen KA, Hall MJ, Golosinskiy A. U.S. outpatient surgeries on the rise, National Health Statistics reports. Hyattsville (MD): National Center for Health Statistics; 2009. [3] Fecho K, Lunney AT, Boysen PG, et al. Postoperative mortality after inpatient surgery: incidence and risk factors. Ther Clin Risk Manag 2008;4:681–8. [4] Hall BL, Hamilton BH, Richards K, et al. Does surgical quality improve in the American College of Surgeons National Surgical Quality Improvement Program: an evaluation of all participating hospitals. Ann Surg 2009;250:363–76. [5] Khuri SF, Henderson WG, Daley J, et al. Successful implementation of the Department of Veterans Affairs’ National Surgical Quality Improvement Program in the private sector: the Patient Safety in Surgery study. Ann Surg 2008;248:329–36. [6] Dimick JB, Osborne NH, Hall BL, et al. Risk adjustment for comparing hospital quality with surgery: how many variables are needed? J Am Coll Surg 2010;210:503–8. [7] Birkmeyer JD, Dimick JB. Understanding and reducing variation in surgical mortality. Annu Rev Med 2009;60:405–15. [8] Berenguer CM, Ochsner MG Jr, Lord SA, et al. Improving surgical site infections: using National Surgical Quality Improvement Program data to institute Surgical Care Improvement Project protocols in improving surgical outcomes. J Am Coll Surg 2010;210:737–41, 741–3. [9] Werner RM, Bradlow ET. Relationship between Medicare’s hospital compare performance measures and mortality rates. JAMA 2006;296:2694–702. [10] McLeod LD, Coon CD, Martin SA, et al. Interpreting patient-reported outcome results: US FDA guidance and emerging methods. Expert Rev Pharmacoecon Outcomes Res 2011;11:163–9.

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