Participants
Thirty-three cancer patients consisting of breast, gynecological, head and neck, colorectal and lymphoma cancer participated in the study. On average, the patients were diagnosed 15 months prior to the time of recruitment. All patients presented with clinical levels of sleep disturbances (PSQI>5), of whom 13 reported borderline or clinical levels of psychological distress (HADS ≥8), and 20 reported non-clinical levels of psychological distress (HADS ≤7). Patients in the non-clinical and borderline to clinical distress group reported a global PSQI score of 9.75±3.36 and 11±3.34 respectively. The non-clinical distress group reported a mean anxiety and depression score of 2.00±1.72 and 1.75±1.07; while the borderline clinical group reported 9.23±1.54 and 7.38±4.19 respectively. Additional demographic and clinical data are presented in Table 1. Pertinent narrative data are presented in tables 2-4, referenced in text below by italicized numbers, (e.g. Table 2, 1.1).
Nature of sleep disturbance (Table 2, 1.1-1.3)
Regardless of the psychological distress level, all patients reported similar patterns of sleep disturbance, including nocturnal waking, long sleep onset latency, and shortened sleep duration.
Patients frequently reported greater sleep onset latency compared to before their cancer diagnosis, sometimes waiting 30 minutes to 4 hours after getting in bed before sleep onset (1.1). Frequent nocturnal wakening with difficulty in resuming sleep after waking in the middle of the night (1.2), together with long sleep onset latency effectively reduced the nighttime sleep duration (1.3) were common problems. Some patients reported large reductions in sleep duration after cancer diagnosis compared to before, with a reduction from approximately eight to five hours (1.3).
Common triggers of sleep disturbances (Table 2, 2.1-2.4)
Common triggers of sleep disturbance were identified for both patients with non-clinical or borderline to clinical levels of distress. These included treatment-related side effects, intrusive thoughts of cancer, fears of cancer recurrence, and non-cancer-related factors.
Treatment-related side effects (2.1)
Treatment brought upon a myriad of physical side effects which contributed to sleep disturbances. For example, a breast cancer patient (Case 20) spoke about how treatment-induced menopausal symptoms, hot flushes and sweating, lead to frequent nocturnal wakening. Persistent symptoms of peripheral neuropathy, including numbing and prickling at night, were experienced by a gynecological cancer patient who had completed chemotherapy (Case 1). Apart from the physical side-effects of treatment contributing to sleep disturbance, patients also perceived treatment to have disrupted their sleep-wake cycle, which was most commonly reported by those who had undergone chemotherapy or radiotherapy. For example, a patient with lymphoma (Case 7) experienced a significant deterioration of sleep quality after receiving a combination of chemotherapy and targeted therapy, which persisted beyond treatment completion.
Extended periods of hospitalization as a result of treatment complications negatively impacted sleep patterns for one patient. Even after being discharged, a patient with head and neck cancer (Case 10) faced difficulties in falling asleep at night, and even struggled to fall asleep in the day when attempting to make up for lost sleep.
Intrusive thoughts about cancer and fear of cancer recurrence (2.2)
Irrespective of level of distress intrusive thoughts about the cancer treatment process, or fears of cancer recurrence and progression were common. Patients reported nightmares disrupting sleep quality in form of vivid flashbacks regarding the cancer treatment process (Case 1) which they perceived as traumatic, painful and frightening. Recalling the trauma of treatment also occurred at night when distractions are fewer, causing difficulty in initiating sleep (Case 27). One patient (Case 5) reported having recurring nightmares of deceased relatives during chemotherapy, which continued regularly after treatment completion. These nightmares often triggered thoughts of the severe consequences of cancer recurrence. Anticipatory anxiety affected sleeping as regular check-ups with oncologists approached, triggering fear of recurrence, adding to existing anxiety (Case 16). Fears of recurrence also accompanied other worries concerning the potential burden that recurrence may have on family members on top of adjustment concerns to cancer, such as the implications of their ability to return to work, which often kept their minds active before falling asleep (Case 20).
Poor sleep hygiene (2.3)
Non-cancer-related factors, such as poor sleep hygiene or disruptive sleeping environments had also contributed to poor sleep. For example, a partner's persistent snoring has been a source of frustration for the patient as it has consistently prevented them from falling asleep (Case 28). Further, a considerable number of patients admitted to the habit of scrolling their phones in bed. Although the patient is aware of the detrimental effects on their sleep quality, they struggle to break free from the habit, as they use it as a way to manage stress after a busy day of work (Case 23).
Lack of routine (2.4)
Many patients noted a lack of employment as having a noticeable effect on sleep quality. For example, a patient (Case 17) observed that having no plans in the day would result in a shortened sleep duration to which they would wake up too early in the morning. Meanwhile, completing the chores and engaging in housework helped them to sleep better. Another perceived that the physical and mental demands of their jobs before retirement would naturally lead to increased daytime fatigue and ultimately result in better sleep quality at night (Case 13).
Differences in experiences of sleep disturbances in patients between varying distress levels
Table 3 documents sleep disturbance experiences in borderline to clinical distress (Table 3.A) versus non-clinical distress (Table 3.B).
Patients with borderline or clinical psychological distress (Table 3.A)
Patients who had higher levels of psychological distress more often reported rumination about their progress towards recovery, and experienced greater concern about how negative emotions and poor sleep might impact their recovery. Consequently, they felt a heightened pressure to maintain good sleep quality. Patients also reported ongoing life stressors and lack of social support as triggers for sleep disturbances.
Rumination about recovery and returning to normal (3.A.1)
Patients with non-clinical and borderline or clinical psychological distress both experienced cancer-related side effects that negatively affected their sleep, however the latter group was found to fixate on their symptoms as an indication of poor recovery progress and inability to return to normal. A patient (Case 8) exhibited unbearable levels of discomfort from treatment side-effects, which prevented them from falling asleep easily. They perceived symptoms as uncontrollable and managing them to be an isolating experience, as they believed the symptoms will last indefinitely. While patients with non-clinical levels of distress tended to see treatment-related symptoms as a natural part of recovery, patients with higher distress levels seemed to find them overwhelming. One patient mentioned having once preferred death over facing their symptoms, particularly during the treatment period, which contributed to disturbing their sleep (Case 25). A patient (Case 15) was observed to exhibit upward comparison; as they had perceived their symptoms to be more severe when comparing with other patients at regular check-ups, which left them with feelings of uncertainty about their recovery.
Worry about negative emotions affecting cancer progression and subsequent thought suppression (3.A.2)
Patients with higher distress frequently expressed worry about whether having negative emotions arising from ruminating about cancer would further impact their health. For example, rumination of their side effects led to additional worry about how these negative emotions would affect their health condition (meta-worry) (Case 8). While conscious efforts to maintain a positive mindset by suppressing negative thoughts were made, patients also acknowledged that this was often challenging (Case 8). Another patient worried whether feelings of anger, triggered by arguments with their partner, would hinder the effectiveness of chemotherapy treatment. This worry in turn caused additional distress, which led them to avoid situations that lead to anger in order to better control their emotions (emotional suppression) (Case 1).
Worry about poor sleep affecting recovery, and subsequent pressure to achieve good sleep (3.A.3)
Many patients with higher distress exhibited concerns about the potential consequences of poor sleep, alike to the above reported effects of negative emotions on cancer recurrence or progression (Case 7). For example, a patient (Case 24) reported that maintaining good sleep was especially important given their history of cancer recurrence.
However, conscious efforts to fall asleep or by taking naps during the day to compensate for lost sleep was counterproductive and instead resulted in increased difficulty to sleep (Case 23). Anxiety over sleep concerns may also be reinforced by their sleep quality of the previous night, fearing their sleep difficulties would continue as they had already experienced it multiple nights in a row (Case 1). Patients may also monitor bodily sensations, such as the level of comfort achieved in their sleeping environment (Case 27) or for any physical symptoms (Case 24), to determine the reasons behind their sleep difficulties.
High sleep reactivity to ongoing life stressors and lack of social support (3.A.4)
Apart from cancer-related factors, patients with higher distress were more likely to exhibit greater rumination towards other sources of stress such as family-related worries, planned engagements for the next day, and work stress, which contributed to increased difficulty in falling asleep (Case 26, 27). Likewise, it was commonly observed by patients that worry for being unable to sleep ultimately resulted in an increased failure to fall asleep (Case 32).
Alongside ongoing life stressors, patients with higher distress often reported having limited social support. For example, arguments that arose from a patient’s dissatisfaction towards the partner’s emotional and financial support towards the patient’s treatment expenses precipitated rumination on these issues before sleep (Case 1). Again, awareness of their negative emotions also became a source of worry for cancer progression. Alternatively, a patient (Case 31) cited the primary cause of her sleep disturbances, aside from cancer, was the burden and stress of being a full-time caregiver for a family member with intellectual disability.
Patients with non-clinical psychological distress (Table 3.B)
Patients who experienced lower levels of psychological distress typically demonstrated acceptance of their illness and treatment process, placed greater emphasis on moving forward with life after cancer, and expressed a shift in personal values to prioritize health. Simultaneously, they placed less fixation on achieving good sleep quality, and were more likely to report comorbid health conditions diagnosed prior to cancer as contributors of sleep disturbance.
Acceptance, resilience and optimism towards cancer and treatment experience (3.B.1)
In contrast to those with higher distress, those with non-clinical distress generally attributed less emotional distress to their treatment side-effects. This was seen in Case 11, where an initial fear of potential radiotherapy side-effects evolved to a positively reappraisal of their cancer treatment journey after realizing that radiotherapy-induced damage was less than anticipated. Further, they were more likely to reframe their perspective by reflecting on the adversities they had faced in the past and used them as sources of motivation for increased personal growth to further overcome future difficulties (Case 14).
Change in life values, and commitment on prioritizing one’s health (3.B.2)
In contrast to those with higher distress, patients with less distress demonstrated a shift in values and priorities after cancer treatment, placing greater emphasis on caring for their health rather than fixating on their recovery progress. For example, a patient (Case 16) displayed a stronger focus on the positive aspects of their cancer treatment experience and demonstrated a commitment to actively seek ways to improve their health. They also expressed that it no longer feels worth it to exert themselves. Instead, they accepted their physical limitations after cancer, made necessary adjustments to their behavior accordingly, and embraced their new normal. Similarly, while one patient (Case 14) shared their perspective on the inevitability of death, they also indicated their commitment to making most of the present moment.
Self-distraction of cancer-related worries to cope with sleep disturbances (3.B.3)
While those with high distress engaged in avoidant strategies, such as disengaging from negative thoughts, those with non-clinical levels of distress conversely engaged in distraction of negative thoughts, by actively engaging in activities, such as mindfulness, or listening to the radio, that redeployed attention to external activities (Case 20; Case 30).
Fewer expectations towards sleep quality (3.B.4)
Compared with those with high distress, patients with non-clinical distress exhibited fewer expectations regarding their sleep quality. Instead, patients tended to accept sleep difficulties if they arose (Case 2). Some patients were not very worried about how much time they slept and whether it would affect their daily functioning (Case 20).
Pre-existing comorbid health conditions lead to sleep disturbance (3.B.5)
Many patients with non-clinical distress had pre-existing conditions that sometimes interfered with sleep, so were more accepting (Case 4). Cancer treatment was perceived by some to have worsened the symptoms of their comorbid conditions (e.g. herniated disc), further exacerbating their pre-existing sleep disturbance (Case 2). Consequently, many reported having become accustomed to sleeping poorly for many years (Case 3), suggesting that their sleep issues were unrelated to cancer.
Common help-seeking behaviors in managing sleep disturbances (Table 4)
Irrespective of distress levels, both groups reported reluctance or opposition to seeking help from oncologists towards sleep disturbances. Patients either underestimated the severity of their sleep problems, believed it to have little effect on their daily lives or prioritized the treatment of other symptoms over sleep disturbance.
Lack of urgency to address sleep disturbances with oncologist (4.1)
Patients with pre-existing sleep disturbance accepted poor sleep as a normal part of their lives (Case 2). They reported that they did not feel that sleep disturbance had a significant impact on their daily functioning, reflecting a lack of urgency in addressing sleep disturbances (Case 32). Some patients perceived other symptoms to be more important to address, such as unexplained pain in their hands and feet (Case 9).
Preference for using Chinese medicine over Western sleep medication (4.2)
Patients universally had negative opinions of sleep medication and Western medication in general, expressing concerns about its potential damaging effects on health and dependence. In contrast, there is widespread consensus in favor of seeking Chinese medicine as a method to treat sleep disturbances and other cancer-related symptoms (Case 4, Case 33)., they believe that traditional Chinese medicine (TCM) unlike allopathic medicine not only improves sleep quality, but also promotes overall health after undergoing cytotoxic cancer treatment, without having negative effects on the body (Case 10).
Perceived lack of support from oncologists for sleep and other health-related matters (4.3)
Reluctance to seek support was often influenced by previous experiences during regular check-ups with oncologists. For example, patients were informed that poor sleep was a normal post-treatment experience; and that there were few options available to manage sleep disturbances (Case 7). Some indicated disappointment or frustration with the oncologists’ responses, as they either felt that their concerns and worries were dismissed (Case 28), or that the oncologists had not provided enough information or guidance on symptom management post-treatment (Case 25). This often led to a sense of helplessness and uncertainty after their appointments.