Post-stroke fatigue: a review of development, prevalence, predisposing factors, measurements, and treatments

Adaptogens in Long-Lasting Brain Fatigue: An Insight from Systems Biology and Network Pharmacology

Long-lasting brain fatigue is a consequence of stroke or traumatic brain injury associated with emotional, psychological, and physical overload, distress in hypertension, atherosclerosis, viral infection, and aging-related chronic low-grade inflammatory disorders. The pathogenesis of brain fatigue is linked to disrupted neurotransmission, the glutamate-glutamine cycle imbalance, glucose metabolism, and ATP energy supply, which are associated with multiple molecular targets and signaling pathways in neuroendocrine-immune and blood circulation systems. Regeneration of damaged brain tissue is a long-lasting multistage process, including spontaneously regulating hypothalamus-pituitary (HPA) axis-controlled anabolic-catabolic homeostasis to recover harmonized sympathoadrenal system (SAS)-mediated function, brain energy supply, and deregulated gene expression in rehabilitation. The driving mechanism of spontaneous recovery and regeneration of brain tissue is a cross-talk of mediators of neuronal, microglia, immunocompetent, and endothelial cells collectively involved in neurogenesis and angiogenesis, which plant adaptogens can target. Adaptogens are small molecules of plant origin that increase the adaptability of cells and organisms to stress by interaction with the HPA axis and SAS of the stress system (neuroendocrine-immune and cardiovascular complex), targeting multiple mediators of adaptive GPCR signaling pathways. Two major groups of adaptogens comprise (i) phenolic phenethyl and phenylpropanoid derivatives and (ii) tetracyclic and pentacyclic glycosides, whose chemical structure can be distinguished as related correspondingly to (i) monoamine neurotransmitters of SAS (epinephrine, norepinephrine, and dopamine) and (ii) steroid hormones (cortisol, testosterone, and estradiol). In this narrative review, we discuss (i) the multitarget mechanism of integrated pharmacological activity of botanical adaptogens in stress overload, ischemic stroke, and long-lasting brain fatigue; (ii) the time-dependent dual response of physiological regulatory systems to adaptogens to support homeostasis in chronic stress and overload; and (iii) the dual dose-dependent reversal (hormetic) effect of botanical adaptogens. This narrative review shows that the adaptogenic concept cannot be reduced and rectified to the various effects of adaptogens on selected molecular targets or specific modes of action without estimating their interactions within the networks of mediators of the neuroendocrine-immune complex that, in turn, regulates other pharmacological systems (cardiovascular, gastrointestinal, reproductive systems) due to numerous intra- and extracellular communications and feedback regulations. These interactions result in polyvalent action and the pleiotropic pharmacological activity of adaptogens, which is essential for characterizing adaptogens as distinct types of botanicals. They trigger the defense adaptive stress response that leads to the extension of the limits of resilience to overload, inducing brain fatigue and mental disorders. For the first time, this review justifies the neurogenesis potential of adaptogens, particularly the botanical hybrid preparation (BHP) of Arctic Root and Ashwagandha, providing a rationale for potential use in individuals experiencing long-lasting brain fatigue. The review provided insight into future research on the network pharmacology of adaptogens in preventing and rehabilitating long-lasting brain fatigue following stroke, trauma, and viral infections.

Dysphagia increases the risk of post-stroke fatigue

BACKGROUND

Post-stroke dysphagia is known to have a pronounced effect on mortality and quality of life of stroke patients. Here, we investigate whether this extends to post-stroke fatigue, a major contributor to morbidity after ischemic stroke.

METHODS

Patients with acute ischemic stroke (recruited consecutively in the STROKE-CARD Registry from 2020 to 2023 at the study center Innsbruck, Austria) were examined for dysphagia via clinical swallowing examination at hospital admission. Post-stroke fatigue was assessed using the Fatigue Severity Scale (FSS) at study specific in person follow-up visits within the first year after ischemic stroke.

RESULTS

Among 882 ischemic stroke patients (mean age 72.4 ± 13.5 years, 36.8% females), dysphagia was present in 22.0% at hospital admission and persisted in 16.2% until hospital discharge. Post-stroke fatigue affected 52.2% of the total cohort during follow-up and was significantly more prevalent among those with dysphagia (68.4% vs. 49.0%, p < 0.001). The prevalence of fatigue increased with the severity of dysphagia, with the highest proportion (86.7%) in those with severe dysphagia. After multivariable adjustment for other factors associated with post-stroke fatigue, including age, sex, pre-stroke disability, cognitive impairment, stroke severity, inability to walk at discharge, and need for antidepressants at discharge, dysphagia remained independently associated with post-stroke fatigue during the first year after stroke (odds ratio [OR]: 2.03, 95% confidence interval [CI]: 1.22-3.38).

CONCLUSIONS

Dysphagia is common after ischemic stroke and increases the risk of post-stroke fatigue. Patient-tailored measures are warranted to reduce fatigue after stroke and therefore enhance quality of life.

Cardiorespiratory fitness, physical activity, and fatigue three months after first-ever ischemic stroke

BACKGROUND

Research on cardiorespiratory fitness (CRF) in relation to physical activity (PA) and fatigue after stroke is limited. Increased knowledge of interrelationships between these factors can help optimize rehabilitation strategies and improve health-outcomes.

OBJECTIVES

We aimed to: 1) evaluate CRF, PA, and fatigue, 2) characterize patients with impaired versus non-impaired CRF, and 3) examine associations of CRF with PA and fatigue, three months after first-ever ischemic stroke.

METHODS

In this cross-sectional study CRF was measured as peak oxygen uptake (VO2peak) by cardiopulmonary exercise testing. PA was measured using accelerometers. Fatigue was assessed with the 7-item Fatigue Severity Scale (FSS).

RESULTS

The sample (n=74, mean age 64±13 years, 36% women) had a mean VO2peak of 27.0±8.7 (86% of predicted). Fifty-one percent met the World Health Organization's recommendation of ≥150 min of moderate PA/week. Mean steps-per-day was 9316±4424 (113% of predicted). Thirty-five percent of the sample had moderate-to-high fatigue (FSS≥4), mean FSS score was 3.2±1.8.  Patients with impaired CRF (VO2peak<80% of predicted) had higher body-fat-percent (p<0.01), less moderate-to-vigorous PA (MVPA) (p<0.01) and a trend toward higher fatigue (p=0.053) compared to the non-impaired. Backward regression analysis showed that higher CRF was associated with more MVPA (unstandardized beta [95% CI]: 0.38 [0.15, 0.63], p=0.002) and less fatigue (unstandardized beta [95% CI]: -3.9 [-6.4, -1.6], p=0.004).

CONCLUSIONS

Stroke patients had lower CRF compared to reference values. Impaired CRF was mainly related to overweight. Higher CRF was associated with more MVPA and less fatigue. Exercise after stroke may be especially beneficial for patients with impaired CRF.

Increased risk of depression and associated symptoms in poststroke aphasia

Poststroke aphasia hinders patients' emotional processing and social adaptation. This study estimated the risks of depression and related symptoms in patients developing or not developing aphasia after various types of stroke. Using data from the US Collaborative Network within the TriNetX Diamond Network, we conducted a retrospective cohort study of adults experiencing their first stroke between 2013 and 2022. Diagnoses were confirmed using corresponding International Classification of Diseases, Tenth Revision, Clinical Modification codes. Patients were stratified by poststroke aphasia status and stroke type, with propensity score matching performed to control for confounders. The primary outcome was depression within one year post-stroke; secondary outcomes included anxiety, fatigue, agitation, emotional impact, and insomnia. Each matched group comprised 12,333 patients. The risk of depression was significantly higher in patients with poststroke aphasia (hazard ratio: 1.728; 95% CI 1.464-2.038; p < 0.001), especially those with post-hemorrhagic-stroke aphasia (hazard ratio: 2.321; 95% CI 1.814-2.970; p < 0.001). Patients with poststroke aphasia also had higher risks of fatigue, agitation, and emotional impact. Anxiety and insomnia risks were higher in those with post-hemorrhagic-stroke aphasia. Poststroke aphasia, particularly post-hemorrhagic-stroke aphasia, may increase the risks of depression and associated symptoms, indicating the need for comprehensive psychiatric assessments.

Early poststroke clinically significant fatigue predicts functional independence: a prospective longitudinal study

Background

Poststroke fatigue is a prevalent issue among stroke survivors, significantly impeding functional recovery and diminishing their quality of life.

Aim

This prospective cohort study aims to investigate the association between poststroke fatigue and the extent of functional recovery in survivors of ischemic and hemorrhagic strokes. Additionally, it seeks to delineate the temporal progression of poststroke fatigue in these two stroke subtypes.

Methods

We assessed a cohort of 79 patients recovering from acute ischemic or hemorrhagic strokes. Poststroke fatigue was quantified using the Fatigue Severity Scale (FSS) and the Numeric Rating Scale (NRSfatigue). Patients' condition was evaluated using the National Institute of Health Stroke Scale (NIHSS), and functional independence levels were determined using the Barthel Index for Activities of Daily Living (BIADL) and the Modified Rankin Scale (MRS). Depressive mood and pain were measured using the Beck Depression Inventory (BDI) and the Numeric Rating Scale for pain (NRSpain), respectively.

Results

Our primary findings indicate that the early manifestation of clinically significant fatigue (CSF) is predictive of a poorer trajectory in functional independence levels during recovery. Furthermore, we observed differing patterns of fatigue progression between ischemic and hemorrhagic strokes. Fatigue tends to ameliorate over time in hemorrhagic stroke cases, paralleling functional recovery, while it remains stable over time in ischemic stroke cases.

Conclusion

Our results underscore the detrimental impact of early poststroke fatigue on long-term outcomes. Furthermore, they highlight the imperative of managing poststroke fatigue, particularly during the subacute phase of stroke recovery.

The impact of post-stroke fatigue on inpatient rehabilitation outcomes: An observational study

BACKGROUND

Post-stroke fatigue is a typical complication following stroke. However, existing research primarily focused on its underlying mechanisms, and its impact on rehabilitation outcomes has yet to be uncovered.

OBJECTIVE

This study aims to explore the impact of post-stroke fatigue on rehabilitation outcomes during hospitalization.

METHOD

This was a prospective multicenter observational study including 46 stroke patients receiving comprehensive rehabilitation treatment. Patients' basic information was recorded upon admission and patients' functional independence was assessed with Functional Independence Measure (FIM) both upon admission and discharge. One week after rehabilitation treatment, fatigue, positivity in daily activity, attention, and memory were assessed. Serum biochemical indicators and levels of C-reactive protein (CRP) were assessed weekly following admission. The pain scores were assessed during the first week of hospitalization to calculate the average. Correlation analysis, linear regression and propensity score matching (PSM) were used to analyze the impact of fatigue on FIM scores at discharge and length of hospital stay.

RESULT

The proportion of patients with low fatigue was 39.13% and significant improvement was revealed in FIM scores upon admissions and discharge [(50.67±18.61) vs. (75.13±21.04), P<0.05]. Positivity in daily activity, attention, and age are factors that influence post-stroke fatigue. After PSM, low-fatigue group (Fatigue score< 3) showed significant higher motor function independence at discharge [(54.39 ± 15.42) vs. (41.89 ± 14.90), P<0.05] and shorter hospital stay [(28.54±9.13)d vs. (37.32 ± 9.81)d, P<0.05] than high-fatigue group. There was a significant difference (P<0.05) in level of CRP between the first inpatient week and the third week, with declining trend.

CONCLUSION

Post-stroke fatigue can affect the rehabilitation outcomes regarding motor function independence and length of hospital stay.