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.

Development and evaluation of the Norwegian Fatigue Characteristics and Interference Measure (FCIM) for stroke survivors: cognitive interviews and Rasch analysis.

PURPOSE: There is need for a comprehensive measure of post-stroke fatigue with sound measurement properties. This study aimed to develop the Norwegian Fatigue Characteristics and Interference Measure (FCIM) and assess its content validity, structural validity, and internal consistency. METHOD: This study consisted of three steps: (1) an expert panel developed version 1.0 of the Norwegian FCIM, (2) its content validity was assessed in cognitive interviews with stroke patients (N = 15), (3) a convenience sample of stroke patients (N = 169) completed an online questionnaire with the FCIM, Fatigue Severity Scale, and sociodemographic information; validity and reliability were assessed using Rasch analysis. RESULTS: FCIM version 1.0 included a 10-item characteristics subscale, a 20-item interference subscale, and two pre-stroke fatigue items. The cognitive interviews revealed content validity issues, resulting in two interference items being removed and five items being flagged but retained for Rasch analysis (version 2.0). Rasch analysis led to removal of four items from the characteristics subscale and six more from the interference subscale. The final six-item characteristics subscale and 12-item interference subscale (version 3.0) both showed adequate fit to the Rasch model with indications of unidimensionality and local independence. The interference subscale had a high person separation index. No significant differential item function (DIF) was found in relation to gender, but one item demonstrated DIF in relation to age. CONCLUSION: The cognitive interviews and Rasch analysis demonstrated that the Norwegian version of the FCIM has high content validity, structural validity, and internal consistency. Future research should assess its construct validity, reliability, and responsiveness.

Association of post-stroke fatigue with physical activity and physical fitness: A systematic review and meta-analysis.

BACKGROUND: It has been hypothesized that post-stroke fatigue (PSF) is associated with reduced physical activity (PA) and impaired physical fitness (fitness). Understanding associations between PSF and PA, and/or fitness could help guide the development of targeted exercise interventions to treat PSF. AIMS: Our systematic review and meta-analysis aimed to investigate PSF's associations with PA and fitness. SUMMARY OF REVIEW: Following a registered protocol, we included studies with cross-sectional or prospective observational designs, published in English or a Scandinavian language, which reported an association of PSF with PA and/or fitness in adult stroke survivors. We searched MEDLINE, Embase, AMED, CINAHL, PsycINFO, ClinicalTrials.gov, and World Health Organization's International Clinical Trials Registry Platform from inception to November 30, 2022. Risk of bias was assessed using Quality in Prognosis Studies. Thirty-two unique studies (total n = 4721 participants, 55% male), and three study protocols were included. We used random-effects meta-analysis to pool data for PA and fitness outcomes, and vote-counting of direction of association to synthesize data that could not be meta-analyzed. We found moderate-certainty evidence of a weak association between higher PSF and impaired fitness (meta r = -0.24; 95% confidence interval (CI) = -0.33, -0.15; n = 905, 7 studies), and very low-certainty evidence of no association between PSF and PA (meta r = -0.09; 95% CI = -0.34, 0.161; n = 430, 3 studies). Vote-counting showed a higher proportion of studies with associations between higher PSF and impaired fitness (pˆ = 0.83; 95% CI = 0.44, 0.97; p = 0.22, n = 298, 6 studies), and with associations between higher PSF and lower PA (pˆ = 0.75; 95% CI = 0.51, 0.90; p = 0.08, n = 2566, 16 studies). Very low- to moderate-certainty evidence reflects small study sample sizes, high risk of bias, and inconsistent results. CONCLUSIONS: The meta-analysis showed moderate-certainty evidence of an association between higher PSF and impaired fitness. These results indicate that fitness might protect against PSF. Larger prospective studies and randomized controlled trials evaluating the effect of exercise on PSF are needed to confirm these findings.

Post-stroke fatigue: an exploratory study with patients and health professionals to develop a patient-reported outcome measure.

BACKGROUND: Post-stroke fatigue (PSF) is commonly reported and described as disabling by patients recovering from stroke. However, a major challenge is how to accurately diagnose and assess PSF. Therefore, the aim of this study was to explore PSF as it is experienced by stroke survivors and described by health professionals to guide future development of a PSF-specific PROM. METHODS: Individual semi-structured interviews were conducted with stroke survivors experiencing PSF (n = 9) and three focus groups were conducted with health professionals (n = 16). Data were analyzed through inductive content analysis. RESULTS: The analysis revealed four themes illustrating the experience and descriptions of PSF: 1) PSF characteristics, 2) interfering and aggravating factors, 3) management, and 4) PSF awareness, which refers to stroke survivors first becoming aware of PSF after their initial hospital admission. CONCLUSION: This study highlights the complexity and multidimensionality of PSF. The results from this study will guide future development of a PSF-PROM and support its content validity.

An evaluation of the short physical performance battery following pulmonary rehabilitation in patients with chronic obstructive pulmonary disease.

OBJECTIVE: There is a need for simple tools to evaluate physical performance in patients with COPD before and after pulmonary rehabilitation. The aims of this study were to evaluate changes in short physical performance battery (SPPB)-scores in patients with COPD after a 4-week pulmonary rehabilitation program; explore possible relationships between SPPB-scores and exercise capacity (6-min walk distance), dyspnea (modified Medical Research Council's dyspnea scale), disease-specific quality of life (COPD assessment test), and pulmonary function (predicted forced expiratory volume in one second) at baseline; and explore if changes in SPPB-scores are related to changes in exercise capacity, dyspnea, and disease-specific quality of life following pulmonary rehabilitation. RESULTS: Forty-five patients with COPD were included in the final analysis. SPPB-scores improved following pulmonary rehabilitation (mean change: 1.2 ± 1.7 points, p < 0.001). There were moderate correlations between SPPB-scores and exercise capacity (r = 0.50, p < 0.001) and dyspnea (r = - 0.45, p = 0.003) at baseline, but not with pulmonary function or disease-specific quality of life. Changes in SPPB-scores were not associated with changes in exercise capacity or dyspnea scores. The SPPB may be a useful tool for evaluating physical performance in COPD Trial registration ClinicalTrials.gov NCT02314338, December 11, 2014.

UVA/B-induced apoptosis in human melanocytes involves translocation of cathepsins and Bcl-2 family members.

We demonstrate UVA/B to induce apoptosis in human melanocytes through the mitochondrial pathway, displaying cytochrome c release, caspase-3 activation, and fragmentation of nuclei. The outcome of a death signal depends on the balance between positive and negative apoptotic regulators, such as members of the Bcl-2 protein family. Apoptotic melanocytes, containing fragmented nucleus, show translocation of the proapoptotic proteins Bax and Bid from the cytosol to punctate mitochondrial-like structures. Bcl-2, generally thought to be attached only to membranes, was in melanocytes localized in the cytosol as well. In the fraction of surviving melanocytes, that is, cells with morphologically unchanged nucleus, the antiapoptotic proteins Bcl-2 and Bcl-X(L) were translocated to mitochondria following UVA/B. The lysosomal proteases, cathepsin B and D, which may act as proapoptotic mediators, were released from lysosomes to the cytosol after UVA/B exposure. Proapoptotic action of the cytosolic cathepsins was confirmed by microinjection of cathepsin B, which induced nuclear fragmentation. Bax translocation and apoptosis were markedly reduced in melanocytes after pretreatment with either cysteine or aspartic cathepsin inhibitors. No initial caspase-8 activity was detected, excluding involvement of the death receptor pathway. Altogether, our results emphasize translocation of Bcl-2 family proteins to have central regulatory functions of UV-induced apoptosis in melanocytes and suggest cathepsins to be proapoptotic mediators operating upstream of Bax.

Ultraviolet A and B affect human melanocytes and keratinocytes differently. A study of oxidative alterations and apoptosis.

Ultraviolet (UV) radiation is an etiologic agent for malignant melanoma and non-melanoma skin cancer, but the spectral range responsible for tumor induction is still to be elucidated. In this study, we compared effects of UVA and UVB irradiation on normal human melanocytes (MCs) and keratinocytes (KCs) in vitro. We demonstrate that UVA irradiation induces immediate loss of reduced glutathione (GSH) in both MCs and KCs. Exposure to UVA also causes reduced plasma membrane stability, in both cell types, as estimated by fluorescein diacetate retention and flow cytometry. Furthermore, we noted reduction in proliferation and higher apoptosis frequency 24 h after UVA irradiation. UVB irradiation of KCs caused instant reduction of reduced GSH and impaired plasma membrane stability. We also found decline in proliferation and increased apoptosis after 24 h. In MCs, on the other hand, UVB had no effect on GSH level or plasma membrane stability, although increased apoptotic cell death and reduced proliferation was detected. In summary, MCs and KCs showed similar response towards UVA, while UVB had more pronounced effects on KCs as compared to MCs. These results might have implications for the induction of malignant melanoma and non-melanoma skin cancer.