Quality of Life After Prostate Cancer Treatment: A mixed methods study exploring patients’ experiences of quality of life and its measurement

As survival rates of prostate cancer continue to improve, treatment-related quality of life (QoL) issues of prostate cancer survivors become increasingly pertinent in cancer care. Prostate cancer treatment options cause a variety of side effects, such as erectile dysfunction and urinary incontinence, that are known to affect patients’ QoL and their perception of themselves as a man. However, it remains to some extent unknown why some men report extreme dissatisfaction with their lives while others report full satisfaction in surveys, even when both experience the same treatment side effects. Quantitative studies examine QoL by using both generic QoL measures and disease-specific measures assessing prevalence and severity of symptoms, such as urinary incontinence, bowel symptoms and erectile dysfunction. These measurement techniques are crucial for controlling quality of care. However, they do not take into account the fact that the meaning of these symptoms for patients’ life satisfaction varies between individuals, depending on life situation and social environment. It is important to study these measurement techniques, because they affect the QoL information received and thus the way we comprehend the QoL issues for these patients. In addition, how results from these surveys are interpreted in clinical work may also affect the support and treatment that is offered to patients suffering adverse treatment side effects.

This doctoral thesis comes from the field of health sciences and enlightens the relation between measuring and experiencing quality of life by using both quantitative and qualitative methods with the same study participants. The study explores different aspects of QoL experience and patient experience of the Expanded Prostate Cancer Index Composite Short Form (EPIC-26), using a mixed methods approach. The study contributes to methodological discussion on best practices of measuring QoL in prostate cancer patients.

The data includes cross-sectional survey data (n=183), longitudinal survey data (n=625), semi-structured interviews with prostate cancer patients (n=22), and 28 transcribed pages of patients’ spontaneous comments written on survey margins. Descriptive statistics and logistic regression models were used to analyze the survey data to study factors related to self-rated health and life satisfaction after cancer surgery (Article 1). The interviews were analyzed with discourse analysis that focused on the ways men utilized culturally available discursive strategies in reconstructing their masculinity after prostate cancer surgery (Article 2). Spontaneous comment data was analyzed with inductive content analysis to shed light on the factors that hinder answering in EPIC-26. In Article 4, statistical analysis was focused on missing data in EPIC-26 in order to investigate the extent of the previously found barriers in answering, and to offer descriptive information on missing data in this widely used measure. This longitudinal data was analyzed with descriptive statistics and logistic regression. The chosen mixed methods approach in Articles 1-2 and 3-4, combined with the longitudinal statistical data in Article 4, is unique in QoL research and enables discussion on the concept of QoL and its measurement techniques in a novel manner.

In the statistical data, the level of urinary incontinence and erectile dysfunction was linearly associated with general quality of life (self-rated health and life satisfaction). Still, 57% of the survey participants who reported severe feelings of harm related to sexual dysfunction were satisfied with their lives. Interview data with the same participants revealed that the patients’ age and life situation were key elements in coping with the adverse sexual side effects. Older age, a supportive spouse, children, and good health enabled men to reconstruct their identity and masculinity in socially acceptable ways. Also, male friends who accepted the idea of an active sex life being part of younger men’s lives, rather than a requirement for men of their age, were an important resource in coming to terms with erectile dysfunction. Thus, even severe erectile dysfunction will not necessarily threaten a man’s masculine identity and QoL.

Analyses of missing data and patients’ spontaneous comments written in the margins of the EPIC-26 survey revealed that patients had difficulties in answering some of the questions due to a lack of suitable answer options for sexually inactive men or for those using erectile aids. Questions regarding hormonal symptoms were possibly considered female-specific and consequently perceived difficult or embarrassing to answer. For these reasons, patients most often skipped questions regarding sexual and hormonal symptoms. The results suggest that the common QoL measurements in surveys do not sufficiently consider men’s differing life situations. The study revealed several validity issues in EPIC-26 and offers simple suggestions to improve the measure.

Interpretation of any empirical statement about QoL will depend largely on how QoL is defined and assessed in a study. Different treatment side effects are valued uniformly in QoL surveys, but the meaning of these ailments may be significantly different for a patient depending on his life situation. Treatment recommendations are still based on this statistical information, however. When survey data on a patient’s QoL is used for clinical purposes, surveillance purposes and individual treatment recommendations, discussion with the patient about his answers should always be included for a correct interpretation of his situation and support needs.