Women With GAD Have Lower Sleep Quality And Repetitive Negative Thinking

Generalized Anxiety Disorder (GAD) is a mental health condition characterized by excessive, uncontrollable worry about various aspects of life.

Repetitive negative thinking (RNT) involves recurring, intrusive, and negative thoughts, such as worrying about future events (e.g., “What if I fail this exam?”) or ruminating on past experiences (e.g., “I shouldn’t have said that.”).

RNT is a common feature of GAD and can contribute to other symptoms, such as sleep disturbances and fatigue.

Leung, P., Li, S. H., & Graham, B. M. (2022). The relationship between repetitive negative thinking, sleep disturbance, and subjective fatigue in women with Generalized Anxiety Disorder. British Journal of Clinical Psychology, 61(3), 666-679. https://doi.org/10.1111/bjc.12356

Key Points:

• Women with Generalized Anxiety Disorder (GAD) reported lower sleep quality, higher repetitive negative thinking (RNT), and higher physical and mental fatigue compared to women without GAD.
• Sleep quality partially accounted for group differences in both physical and mental fatigue, while RNT fully accounted for these differences.
• The relationship between RNT and both types of fatigue was fully explained by sleep quality.
• These findings suggest that elevated RNT in women with GAD may lead to increased physical and mental fatigue through its negative impact on sleep quality.
• Targeting RNT in GAD treatment could potentially help alleviate fatigue symptoms by improving sleep quality.

Rationale

Fatigue is a prominent symptom of Generalized Anxiety Disorder (GAD), but the mechanisms contributing to this elevated fatigue are not well understood (McCallum et al., 2019).

Sleep disturbance, which frequently co-occurs with anxiety (Cox & Olatunji, 2020), has been shown to only partially account for elevated fatigue in GAD (McCallum et al., 2019).

Repetitive negative thinking (RNT), a cognitive feature of both GAD and sleep disturbance, has been associated with fatigue in various conditions such as insomnia, major depressive disorder, and multiple sclerosis (Carney et al., 2014; Hare et al., 2019; Harris et al., 2021).

Additionally, rumination and worry have been found to predict higher fatigue in the general population and workforce, with sleep disturbance mediating these effects (Andrea et al., 2004; Querstret & Cropley, 2012; Thorsteinsson et al., 2019).

However, the potential role of RNT in contributing to heightened fatigue in anxiety disorders, particularly GAD, has not been assessed.

Understanding the role of RNT and how it can affect fatigue and sleep quality can provide a better understanding of methods in which to help people with GAD manage when anxiety strikes at bedtime.

Therefore, this study aimed to examine whether RNT and self-reported sleep quality together account for elevated physical and mental fatigue in women with GAD compared to women without GAD.

Method

Procedure

Between-group, correlational design

Women completed self-report questionnaires assessing:

• RNT experienced in the past few days
• Previous night’s sleep quality
• Current physical and mental fatigue

Sample

• 64 primarily university-educated women
• With and without a GAD diagnosis

Measures

• Repetitive Thinking Questionnaire (RTQ-10): A 10-item questionnaire that assesses repetitive negative thinking (RNT) in response to a recent stressful event. Participants rate items on a 5-point Likert scale, with higher scores indicating greater levels of RNT.
• Pittsburgh Sleep Quality Index (PSQI): A 19-item questionnaire that evaluates sleep quality and disturbances over the past month. It generates a global score and seven component scores (subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleeping medication, and daytime dysfunction). Higher scores indicate poorer sleep quality.
• Multidimensional Fatigue Inventory (MFI-20): A 20-item questionnaire that assesses five dimensions of fatigue: general fatigue, physical fatigue, mental fatigue, reduced motivation, and reduced activity. Participants rate items on a 5-point Likert scale, with higher scores indicating greater levels of fatigue. For this study, only the physical and mental fatigue subscales were used.

Statistical measures

• Hierarchical linear regressions to assess the relationship between GAD status and fatigue, accounting for RNT and sleep quality

Results

The study found that women with GAD reported lower sleep quality, higher RNT, and higher levels of both physical and mental fatigue compared to women without GAD.

Sleep quality partially accounted for the group differences in both types of fatigue (β’s > −0.4), while RNT fully accounted for these differences (β’s > 0.29).

Furthermore, the relationship between RNT and both physical and mental fatigue was fully explained by sleep quality (β’s > −0.39).

Insight

The key findings of this study suggest that women with GAD experience elevated levels of physical and mental fatigue, which can be attributed to their heightened levels of repetitive negative thinking (RNT) and its detrimental effects on sleep quality.

This research extends previous findings by identifying RNT as a potential mechanism contributing to fatigue in GAD, beyond the already established role of sleep disturbance.

The study highlights the importance of addressing RNT in the treatment of GAD, as it may not only alleviate the core symptoms of the disorder but also improve sleep quality and, consequently, reduce fatigue.

Future research could focus on developing and testing targeted interventions that specifically address RNT in GAD, such as cognitive-behavioral techniques or mindfulness-based approaches.

Additionally, longitudinal studies could help establish the temporal relationships between RNT, sleep disturbance, and fatigue in GAD, providing further insights into the causal pathways involved.

Moreover, the findings of this study may have implications for understanding fatigue in other mental health conditions characterized by high levels of RNT, such as depression or other anxiety disorders.

Investigating the role of RNT and sleep disturbance in fatigue across different psychiatric conditions could lead to the development of transdiagnostic interventions targeting these common mechanisms.

Strengths

The study had several methodological strengths, including:

1. The use of a between-group design, which allowed for the comparison of women with and without GAD, providing insights into the unique characteristics of fatigue, RNT, and sleep quality in GAD.
2. The focus is on a specific demographic (primarily university-educated women), which helps to reduce potential confounding factors related to gender, education, or age.
3. The assessment of both physical and mental fatigue, acknowledging the multidimensional nature of fatigue and providing a more comprehensive understanding of the symptom in GAD.
4. The use of self-report questionnaires, which allowed for the efficient collection of data on RNT, sleep quality, and fatigue experienced by participants in their daily lives.
5. The application of hierarchical linear regressions, which enabled the examination of the unique contributions of RNT and sleep quality to the relationship between GAD status and fatigue, while controlling for potential confounding factors.
6. The temporal proximity of the assessments (RNT in the past few days, sleep quality from the previous night, and current fatigue), which helps to capture the dynamic interplay between these variables and reduces the influence of retrospective bias.

Limitations

The study had some limitations that should be considered when interpreting the results:

1. The sample consisted of primarily university-educated women, which may limit the generalizability of the findings to other populations, such as men, individuals with different educational backgrounds, or older adults.
2. The use of self-report questionnaires may be subject to response bias or inaccuracies in participants’ recollections of their experiences. Objective measures of sleep (e.g., actigraphy) and fatigue (e.g., cognitive or physical performance tasks) could provide additional insights.
3. The cross-sectional design of the study precludes the determination of causal relationships between RNT, sleep quality, and fatigue. Longitudinal studies are needed to establish the temporal sequence and potential bidirectional relationships between these variables.
4. The study focused on a specific type of RNT (related to a recent stressful event) and may not capture the full range of RNT experiences in GAD. Future research could explore the role of different types of RNT (e.g., worry, rumination) in relation to fatigue.
5. The study did not assess other potential contributing factors to fatigue in GAD, such as physical activity levels, medication use, or comorbid health conditions. Controlling for these variables in future studies could provide a more comprehensive understanding of the mechanisms underlying fatigue in GAD.

Implications

The results of this study have significant implications for the understanding and treatment of fatigue in Generalized Anxiety Disorder (GAD).

By identifying repetitive negative thinking (RNT) as a key factor contributing to elevated physical and mental fatigue in women with GAD, the findings suggest that targeting RNT in clinical interventions may be an effective strategy for alleviating fatigue symptoms.

In clinical psychology practice, incorporating techniques that address RNT, such as cognitive restructuring, mindfulness-based interventions, or metacognitive therapy, could be beneficial for individuals with GAD who experience significant fatigue.

By reducing RNT and improving sleep quality, these interventions may lead to improvements in overall functioning and quality of life for those affected by GAD.

Furthermore, the findings highlight the importance of assessing and monitoring RNT, sleep quality, and fatigue in individuals with GAD. Clinicians should be aware of the potential interplay between these variables and consider them when developing treatment plans and evaluating treatment outcomes.

The study also underscores the need for further research to investigate the effectiveness of interventions targeting RNT for the reduction of fatigue in GAD.

Additionally, exploring the role of RNT and sleep disturbance in fatigue across other mental health conditions could lead to the development of transdiagnostic approaches that address these common mechanisms.

Overall, the results of this study have the potential to inform clinical practice and guide future research efforts in understanding and treating fatigue in GAD and other mental health conditions characterized by elevated RNT.

References

Primary reference

Leung, P., Li, S. H., & Graham, B. M. (2022). The relationship between repetitive negative thinking, sleep disturbance, and subjective fatigue in women with Generalized Anxiety Disorder. British Journal of Clinical Psychology, 61(3), 666-679. https://doi.org/10.1111/bjc.12356

Other references

Andrea, H., Beurskens, A. J. H. M., Kant, I. J., Davey, G. C. L., Field, A. P., & van Schayck, C. P. (2004). The relation between pathological worrying and fatigue in a working population. Journal of Psychosomatic Research, 57, 399–407. https://doi.org/10.1016/j.jpsychores.2003.09.013

Carney, C. E., Harris, A. L., Moss, T. G., & Edinger, J. D. (2010). Distinguishing rumination from worry in clinical insomnia. Behaviour Research and Therapy, 48(6), 540-546. https://doi.org/10.1016/j.brat.2010.03.004

Carney, C. E., Moss, T. G., Lachowski, A. M., & Atwood, M. E. (2014). Understanding mental and physical fatigue complaints in those with depression and insomnia. Behavioral Sleep Medicine, 12, 272–289. https://doi.org/10.1080/15402002.2013.801345

Cox, R. C., & Olatunji, B. O. (2020). Sleep in the anxiety-related disorders: A meta-analysis of subjective and objective research. Sleep Medicine Reviews, 51, 101282. https://doi.org/10.1016/j.smrv.2020.101282

Hare, C. J., Crangle, C. J., Carney, C. E., & Hart, T. (2019). Insomnia symptoms, subjective appraisals, and fatigue: A multiple mediation model. Behavioral Sleep Medicine, 17, 269–280. https://doi.org/10.1080/15402002.2017.1342167

Harris, A. L., Carmona, N. E., Moss, T. G., & Carney, C. E. (2021). Testing the contiguity of the sleep and fatigue relationship: A daily diary study. Sleep, 44(5). https://doi.org/10.1093/sleep/zsaa252

McCallum, S. M., Batterham, P. J., Calear, A. L., Sunderland, M., Carragher, N., & Kazan, D. (2019). Associations of fatigue and sleep disturbance with nine common mental disorders. Journal of Psychosomatic Research, 123, 109727. https://doi.org/10.1016/j.jpsychores.2019.05.005

Querstret, D., & Cropley, M. (2012). Exploring the relationship between work-related rumination, sleep quality, and work-related fatigue. Journal of Occupational Health Psychology, 17, 341–353. https://doi.org/10.1037/a0028552

Thorsteinsson, E. B., Brown, R. F., & Owens, M. T. (2019). Modeling the effects of stress, anxiety, and depression on rumination, sleep, and fatigue in a nonclinical sample. Journal of Nervous and Mental Disease, 207, 355–359. https://doi.org/10.1097/NMD.0000000000000973

Keep Learning

Here are some suggested Socratic discussion questions about this paper for a college class:

1. How might the findings of this study inform the development of new interventions for Generalized Anxiety Disorder (GAD)?
2. What are some potential mechanisms through which repetitive negative thinking (RNT) may influence sleep quality and, consequently, fatigue in GAD?
3. How could future research build upon the findings of this study to further our understanding of the relationships between RNT, sleep disturbance, and fatigue in GAD and other mental health conditions?
4. What are the potential implications of these findings for individuals with GAD who are experiencing significant fatigue? How might this knowledge empower them to seek appropriate treatment and manage their symptoms?
5. Considering the limitations of this study, what improvements or additions could be made to the research design to strengthen the conclusions and generalizability of the findings?