What does evidence tell us about the difference between quality of life (QoL) and health related quality of life (HRQoL) and is it easy to differentiate between these two concepts? This is a question I have been exploring recently as I prepare to carry out a research study which will investigate how quality of life changes in patients managed without dialysis once they make the decision not to embark on dialysis. Some patients will die during the course of the study due to advanced age, frailty and associated co morbidity other than renal disease and there is likelt to be changes in QoL. At three-monthly intervals patients will complete tools with the aim of measuring changes in their QoL longitudinally.
Quality of life and HRQoL are used interchangeably in the literature but each has its own meaning. QoL is a broader concept which covers all aspects of life. It can be defined in many ways which makes its measurement difficult. Illness and treatment of that illness can effect a patient’s psychological, social and economic well being as well as biological status; a definition needs to all encompassing whilst allowing for the individuality of each patient to be described. HRQoL has a focus on the effects of illness and specifically on the impact treatment may have on QoL. QoL is therefore broader than HRQoL because it includes evaluation of non-health related features of life whereas HRQoL is connected to an individual’s health or disease status. HRQoL can help us understand the distinction between aspects of life related to health. QoL can help us understand those aspects of life that extend beyond health such as education and the social environment. That said other questions arise –
Do you have to measure all aspects of QoL? is it possible to do that?
Is HRQoL the same as health status?
According to Calman, ‘Quality of life must include all areas of life and experience and take into account impact of illness and treatment (Calman 1984 p 124-25). But within the field of healthcare is it impossible to encompass every aspect of life and every human concern? For this reason it is often easier to explore HRQoL. Health status can effect HRQoL but the two are different. Health status assesses and is concerned with physical and psychological symptoms, disability and social dysfunction but cannot judge the impact of this on a person’s well being. HRQoL is therefore thought of as a person’s subjection perception of the impact of ill health on daily life and includes physical, psychological and social functioning.
In my study I want to explore something wider than just HRQoL. Although I am interested in this and the impact that a supportive and palliative care approach may have on a person’s HRQoL (the impact of the treatment) I also want to explore how people rate their overall QoL taking into account the impact of deciding not to have dialysis on emotional and social needs. The overall aim is to explore and measure QoL in order to understand the impact the treatment decision has on many aspects of a patient’s life. The patients who make this momentous decision will receive palliative care and are often very unwell. It is essential that we have understanding of the impact of treatment and the illness. That said some effects such as pain and emotional effects can only be determined by the patient. Clearly physiological measures or clinician-reported outcomes are unlikely to reflect how a patient feels or functions. Even close carers may report inaccurate proxy judgements about QoL domains.
QoL and HRQoL are different but both aim to capture subjective perception and assessment of a patient’s health and well-being. These perception and assessments cannot be identified through laboratory tests, x-ray or other objective testing. Patients’ must carry out this assessment themselves and tools to collect this data must be selected carefully.
Calman KC. Quality of life in cancer patients–an hypothesis. J Med Ethics. 1984 Sep;10(3):124–127