The impact of hepatobiliary interventions on health and quality of life and health

Health

The Constitution of the World Health Organization (WHO) defines health as a “state of complete physical, mental, and social well-being, not merely the absence of disease.” This definition integrates three components of well-being (physical, mental and social) into a holistic view of health. Physical health reflects the physiologic and biologic components of health and the maintenance of homeostasis. Mental health is the aspect of health that relates to a person’s mental status or their psychological and emotional state. Social health is the ability of a person to engage in the social aspects of life and fill roles within society.

The WHO takes the position that the measurement of health is as important as evaluating the severity of disease. Over time, the perception of disease has evolved from the biomedical concept of disease to the broader biopsychosocial model of disease. The biomedical concept restricts the focus of disease to one of “organic malfunction.” This narrow view was broadened in the biopsychological model, which was first proposed by George Engel in 1977.

“To provide a basis for understanding the determinants of disease and arriving at rational treatments and patterns of healthcare, a medical model must also take into account the patient, the social context in which he [sic] lives, and the complementary system devised by society to deal with the disruptive effects of illness, that is, the physician role and the health care system.”

The biopsychological model encourages healthcare professionals to incorporate all aspects of health into their clinical care and decision making, weighing various aspects of health, as needed, to optimally address the patient’s clinical presentation.

The attention to the effect of a person’s social situation on health has gained increased attention in this century, particularly with regard to how societal differences impact health and health equality. Social determinants of health (SDH) are the “conditions in the environments in which people are born, live, learn, work, play, worship, and age that affect a wide range of health, functioning, and quality-of-life outcomes and risks.” The key areas of SDH are “economic stability, education, social and community context, health and health care, neighborhood and built environment.” To achieve population health, the WHO has called for the evaluation of SDH in clinical care and the incorporation of SDH into research so that the effect of SDH on a person’s health can be recognized, addressed, and measured.

As the biopsychological model has gained acceptance, the question turns from whether health should be assessed to how best evaluate it. The evaluation of health necessarily includes the biomedical aspects provided by objective clinical data. Incorporated into this evaluation are assessments of psychological health including depression, delirium, and suicide screening. Social aspects of health are incorporated into patient assessment by exploring social determinants of health such as by assessing financial toxicity and food and housing insecurity. A patient’s well-being is evaluated using a measure of quality of life (QOL).

Quality of life

QOL has been frequently defined as the “individual’s perception of their position in life in the context of their culture and value systems in which they live and in relation to their goals, expectations, standards, and concerns.” The concept of QOL reflects the experience of an individual and is an evaluation of their own life. It is built on culture, experience, values, goals, expectations, and standards. In the very broadest of terms, QOL is multidimensional and influenced by many factors outside the realm of health/disease, including self-esteem, spirituality, financial security, job satisfaction, and personal freedom. The WHO Quality of Life Group (1998) offered a succinct definition of QOL as “a subjective evaluation that is embedded in a cultural, social and environmental context.”

QOL was first discussed in the literature in the 1960s when it was realized that the extension of life through a medical intervention did not always result in the improvement of QOL. It was also recognized that medical interventions, at times, resulted in a cost to QOL. ^, The term “health-related quality of life” (HRQOL) is often use to describe QOL related to healthcare experiences. HRQOL does not consider factors that affect QOL that are outside of the purview of the healthcare system including cultural, economic, and political factors. Excluding factors that are not managed by clinicians offers an incomplete view of the person by excluding social well-being from assessment, and it devalues the impact of SDH on the health of individuals. It undermines the holistic approach of the biopsychosocial model and takes a narrow view of QOL similar to the narrow view of the biomedical model of disease.

The assessment of QOL is an assessment of a patient-reported outcome (PRO) measure. PRO is “used as an umbrella term for different concepts for measuring subjectively perceived health status.” PRO includes any direct report by a patient of their health condition that has not been interpreted by a clinician or anyone else. PRO measures can assess a single value at one point in time or measure change in that value over time. The psychometrical approach to PRO measures is used most commonly in healthcare. This approach refers to the individual reporting of the presence and quality of perceived symptoms, the functional state, QOL, health behaviors, satisfaction, and emotional and mental status. How the individual reports these measures is their prerogative; however, consensus has not been achieved regarding the definition of concepts measured by PROs. As such, there is an opportunity for additional research in this field.

The interrelationships between different PROs have not been clearly defined. Wilson and Cleary developed a conceptual framework to describe the relationships between five different measures of health. The five measures of health are physiologic and biologic factors, symptoms, functioning, general health perceptions, and overall QOL. This linear model depicts the relationships on a continuum from biologic and physiologic processes to symptoms to function followed by health perceptions, which result in QOL. The framework depicts characteristics of the individual and environment as moderators of health measures. This is a parsimonious model that describes and explains health and can be used to evaluate health outcomes and their relationships with QOL.

Patient report is the key feature of PRO measures. For practical reasons, initial investigations of QOL and other PRO measures used the external judgment of observers, typically nurses or clinicians, to evaluate treatment impact. Examples of this are the commonly used measures of performance such as the Karnofsky Performance Scale (KPS) Index and the Eastern Cooperative Oncology Group (ECOG) Performance Index. These are measures of function and performance, but they are not PROs because they provide the clinician’s perception of the patient’s status, not the patient’s report of their function and performance. This method of evaluating patient outcomes is inherently biased by the observer’s own internal standards. Multiple studies evaluating the degree of agreement between the proxy ratings of QOL by observers to patient assessments have consistently found very little correlation between the two measures. In clinical trial research, up to 76% of cases with severe symptoms are underreported by providers.

The validity of QOL instruments and rigor of results is contingent on patients’ reporting. Unfortunately, this requisite self-reporting can become an issue when patients are followed over time because disease status and symptoms worsen, making completion more challenging. With time, patients are less likely to fill out instruments, leading to nonrandom missing data, which is a significant challenge in QOL research. ^, Feinstein coined the term “sensibility” of QOL instruments to denote the practical issues related to implementation of QOL measurements. All PRO measures must be evaluated before use from the perspective of the patient. The number of items in a measure, the thought required to complete the measure, and the time required to complete a measure can lead to “questionnaire burn-out” and subsequent patient noncompletion. Other issues, such as literacy and preferred language, may prohibit patients from completing instruments independently.

Measurement of quality of life

Essential to the assessment of QOL are instruments developed specifically to measure the construct of QOL. As with the conceptual evolution, assessment of QOL in the clinical setting has been progressive. In the field of oncology, there was a need to assess the “quality of survival” since early chemotherapeutic treatments were severely toxic and there were few options to mitigate the adverse effects. In 1982 the Eastern Cooperative Oncology Group published criteria to measure the toxicity from treatment. All included measures were objective clinical parameters except for their novel performance status scale. In the absence of specific measures of QOL, some researchers reported the ECOG scale and the KPS as surrogates for QOL despite being single unidimensional parameters of performance. With time, the void of valid and reliable instruments for QOL assessment has been filled with multidimensional instruments of QOL with well-established psychometric properties.

The availability of QOL instruments has led to increasing acceptance of their importance as a necessary outcome measure in oncology and surgery. The WHO lists benefits of QOL assessment in clinical practice, including improved decision making, enhanced physician and patient relationship, and better evaluation of treatments. Through the assessment of QOL, a physician learns which patient’s domains are most impacted, and this understanding can drive clinical decisions. The assessment of QOL improves the physician and patient relationship by increasing the physician’s understanding of the patient’s experience. Lastly, QOL assessment allows the physician to evaluate the relative merits and effectiveness of treatment options from a patient’s perspective. ^,

The acceptance of QOL as an important parameter to assess does not overcome the challenges of implementing assessment into routine clinical practice. There are inherent limitations in the assessment and measurement of QOL. As a subjective measurement, individual benefit may go unrecognized within the results of the entire sample. In many cases, specific detected numeric differences in two assessments (e.g., presurgery to postsurgery) have not been correlated with the clinical implication of the findings. Finally, patients may not be able to adequately reflect their experience within the context of an instrument. These limitations need to be acknowledged and present opportunities for additional research and instrument development.