An examination of distress, sleep, and fatigue in metastatic breast cancer patients.

As women live for months or years with metastatic breast cancer, they face a growing dependence on health care professionals and significant others, cognitive and physical decline, and their own mortality. Metastatic breast cancer is considered incurable, with a median survival time of 2 to 4 years following diagnosis [1]. As patients cope with increased physical symptoms, frequent medical appointments, and relational and existential concerns, a substantial minority experience psychological morbidity [2–6]. For example, over 40% of metastatic breast cancer patients were found to have a DSM-IV psychiatric disorder [3–4]. Almost one-third met the criteria for a depressive disorder, whereas 6% met the criteria for an anxiety disorder [3–4]. Similar rates of anxiety and depression have been found in other advanced cancer patient samples; 6% to 8.2% have met the criteria for an anxiety disorder and 14% to 31% have met the criteria for a depressive disorder [7]. Younger advanced cancer patients, including those with metastatic breast cancer, have shown higher rates of depressive disorders [3–4, 8]. Medical treatment variables have not been associated with depressive or anxiety disorders in metastatic breast cancer patients, but have been associated with distress in other advanced cancer populations [3–4, 8]. Depression, cancer, and anti-cancer therapies contribute to the high prevalence of sleep disturbance and fatigue in advanced cancer patients [9–12]. Over 60% of metastatic breast cancer patients reported one or more types of sleep disturbance [12–13], and worsening depression was associated with the greatest number of negative changes in sleep patterns relative to other predictors (pain and life stress) [12]. In heterogeneous samples of advanced cancer patients, fatigue, pain, and psychological distress have predicted sleep disturbance [11, 13–14]. Fatigue, defined as a subjective sense of tiredness or weakness [15], is experienced by many patients who undergo cancer treatment [16]. One study found that over half of metastatic breast cancer patients reported high levels of fatigue [17]. Fatigue reduces physical and psychological well-being [10, 16, 18] and is often one of the key reasons for patients’ discontinuation of anti-cancer therapy [19]. To date, little research has documented the degree of fatigue and sleep problems among distressed women with metastatic breast cancer. In addition, distress has been evaluated using structured clinical interviews and questionnaires that are not easily administered and scored in routine clinical practice. To our knowledge, this study is the first to use the single-item Distress Thermometer (DT) [20] to assess the prevalence of distress among metastatic breast cancer patients. Knowledge of the frequency of distress in this population based on a rapid screening tool and further characterization of the nature of distress and its predictors could inform clinical care. Prior research with a variety of cancer populations has found that 43% to 61% of patients report clinically significant distress (score ≥ 4) on the DT [21–24], and younger age and functional impairment have generally been associated with greater distress [21–23]. Secondary objectives of this study were to characterize the degree of elevated anxiety and depressive symptoms, sleep problems, and fatigue among metastatic breast cancer patients who met the cutoff on the DT for probable distress (score ≥ 4) [22]. In addition, we examined associations between study outcomes and demographic variables, medical factors, and mental health service use. Predictors of mental health service use and meeting the criteria for significant anxiety or depressive symptoms were analyzed separately. Study participants were completing assessments in the context of a randomized clinical trial on the health effects of expressive writing. We present data collected prior to randomization and intervention.