Severe fatigue occurs in one in four breast cancer survivors. Quality of life and psychological factors are important in fatigue-oriented interventions. There is a relationship between fatigue and depressive symptoms, anxiety, distress, sleep disturbances, lower physical activity levels, pain, difficulties coping with cancer and catastrophizing about symptoms.
Breast cancer is the most prevalent type of cancer for women. There are breast cancer survivors who experience debilitating symptoms after curative cancer treatment. Cancer-related fatigue refers to a distressing, persistent, subjective sense of physical, emotional and cognitive tiredness related to cancer or cancer treatment that is not proportional to recent activity and interferes with usual functioning.
The risk for cancer-related fatigue appears to decrease after six months after breast cancer treatment. The risk for severe fatigue is increased for patients in higher disease stages. The risk is lower for patients with a partner and had received surgery. Cancer-related fatigue often does not have a known biological cause. Exercise and psychological interventions appear effective against cancer-related fatigue.
Quality of life refers to individuals’ perception of their position in life in the context of the culture and value systems in which the live and in relation to their goals, expectations, standards and concerns. This concept incorporates a person’s physical and mental health.
There are several important relationships:
- A relationship exists between level of fatigue and quality of life in patients (strong).
- A relationship exists between fatigue and physical functioning (strong).
- A relationship exists between fatigue and cognitive functioning (strong).
- A relationship exists between fatigue and emotional functioning (strong).
- A relationship exists between fatigue and social functioning (strong).
- A relationship exists between fatigue and sexual functioning (moderate).
- A relationship exists between fatigue and work ability (moderate).
The type of evidence is phrased after the relationship (i.e. moderate, strong). There are also other important relationships:
- Higher levels of fatigue are related to lower mental health (moderate).
- Higher levels of fatigue are related to more emotional problems (strong).
- Higher levels of fatigue are related to more sleep disturbances (strong).
- Higher levels of fatigue are related to lower sleep quality (moderate).
- Higher levels of fatigue are related to lower activity levels (strong).
- Higher levels of fatigue are related to more pain (strong).
- Higher levels of fatigue are related to a negative body image (moderate).
- Higher levels of fatigue are related to a more negative future perspective (moderate).
- Higher levels of fatigue are related to more catastrophizing about symptoms (strong).
The most identified symptoms of the emotional problems breast cancer survivors experience are depressive symptoms (1), anxiety-related symptoms (2) and distress (3). The most common sleep disturbance that breast cancer survivors experience is insomnia. Catastrophizing reflects a tendency to engage in negative self-statements and overly negative thoughts about the future regarding fatigue.
Changing dysfunctional cognitions (e.g. focusing on symptoms) can decrease fatigue severity. Sexual functioning could play an important role in the treatment of cancer-related fatigue.
Protective psychological factors (e.g. mindfulness, optimism) may mediate effects of fatigue-oriented interventions.
