Current methodological approaches to the study of sleep disturbances and quality of life in adults with cancer: a systematic review

Abstract

In recent years, sleep disturbances and the health-related quality of life (QOL) experienced by adults with cancer, during and after cancer treatment, have received increasing attention in the scientific literature. The purpose of this paper was to systematically review current methodological approaches to the study of sleep disturbances and QOL in adults with cancer. Databases were searched to identify longitudinal studies of adults with cancer that measured sleep disturbances and QOL in the past 10 years. The review was focused in five primary areas: trends in publication, measurement of sleep and QOL, study design, changes in sleep disturbances and QOL, and the level of this evidence. Of the 40 studies that met the authors' criteria for inclusion, 75% were descriptive in design and 25% were intervention studies. Studies on sleep and QOL among cancer patients have become more common since 2000, include a range of sample sizes and settings, use a variety of measures of sleep and QOL, and examine patients undergoing many types of cancer therapies. No programs of research have been developed in sleep disturbances and QOL in adults with cancer. The 'evidence' that can be drawn from such studies is obviously weak. Current approaches usually describe changes over time, but have not described whether a relationship exists between sleep disturbances and QOL in adults with cancer. Directions for future research are suggested.

Impact of breast cancer treatments on sleep disturbances – A systematic review

“…In fact, several studies were excluded because they did not evaluate sleep with standardized sleep-specific measures. Similar findings were observed in a previous systematic review regarding the methodological approaches of sleep disturbances and quality of life in adults with cancer: of the 40 studies included only four used a multi-item sleep specific instrument [7]. According to the recommendations for a standard research assessment of sleep or insomnia symptoms, in epidemiological studies, these characteristics should be evaluated with global sleep and insomnia measures (namely PSQI and Insomnia Severity Index), sleep diary, actigraphy or polysomnography [47].…”

“…However, different terms related to sleep disorders have been used in the literature, namely sleep disturbances, insomnia, impaired sleep, sleep patterns and sleep-wake disturbances. Since most of the studies in this topic include the evaluation of sleep disorders, global sleep quality or other sleep characteristics, sleep disturbances have been previously used to name all sleep-related outcomes [7].…”

Sleep Quality of Patients with Differentiated Thyroid Cancer

“…It can cause daytime fatigue, lead to mood disturbances, and impair memory and concentration [15, 16]. In many cases, increasing pain perception and immune-suppression can also happen [17]. Although cancer patients of any type would suffer from sleep problem, the nature of which has not been fully described.…”

Sleep–wake disturbances in cancer patients: narrative review of literature focusing on improving quality of life outcomes

“…Data collected included: date, patient demographics, cancer type, treatment/timeframe, study design, measurement variables, and results. Inclusion criteria were: 1) peer-reviewed original research or secondary analysis of subjects with a cancer diagnosis (omitting review articles and theses), in which the variables were measured at two or more time points;12 2) QOL and sleep-wake disturbance measures that demonstrated an association between sleep–wake disturbance and QOL (head and neck cancers were omitted due to potential obstructive airway issues); and 3) studies written in the English language, limited to those involving quantitative methods 11…”

“…QOL has been extensively studied in cancer patients, yet sleep disturbance has often not been included as a main study variable 11. Vena et al10 suggest using the two-process model of sleep regulation12 to understand sleep–wake mechanisms in cancer patients, which includes a homeostatic process influenced by previous sleep and wake states and a circadian process that determines the propensity for falling asleep and consolidating sleep. This model can then be used to discuss cancer-related factors that influence a patient’s risk for developing sleep problems, such as: age and sex; cancer and treatment; lifestyle; and psychological well-being.…”