A cohort study on anxiety and perceived recovery 3 and 12 months after mild to moderate stroke.

Background: Anxiety is a common complication of stroke, affecting one in every three stroke survivors. Stroke recovery is a dynamic process, with most recovery occurring within the first 3 months. However, how anxiety affects this dynamic remains unknown. Therefore, this study aimed to investigate how anxiety affects perceived recovery at 3 and 12 months after stroke. Additionally we also examined the change in perceived stroke recovery from 3 to 12 months and its relationship with anxiety. Methods: In this longitudinal study patients with stroke were enrolled at Sahlgrenska University Hospital, Gothenburg, Sweden. The Hospital Anxiety and Depression Scale was used to assess anxiety, and the Stroke Impact Scale was used to assess perceived recovery 3 and 12 months after the stroke. The difference in perceived stroke recovery between the anxiety and no-anxiety groups at 3 and 12 months was analyzed. Changes in perceived stroke recovery were calculated and trichotomized from 3 to 12 months based on clinically significant positive changes (+10 points or more), clinically important negative changes (-10 points or less), or no changes (±9). At 3 and 12 months after the stroke, negative and positive recovery was compared to no change in recovery regarding anxiety scores. Results: This study included 99 patients (44.4% female, median age, 77 years). At 3 and 12 months after the stroke, the median recovery score was 80 out of 100. At 3- and 12-months 17.6 and 15.7% of the patients experienced anxiety, respectively. At both time points, there was a significant association between anxiety and lower perceived stroke recovery (at 3 months: p < 0.001; and 12 months p = 0.002). Among participants with anxiety at 3 or 12 months after stroke, a positive change in recovery from 3 to 12 months was identified (3 months, p = 0.004 and 12 months, p = 0.0014). Conclusion: Anxiety symptoms following a stroke are associated with lower levels of perceived stroke recovery for at least 1 year after the stroke. Identifying patients with anxiety early after stroke may be beneficial for identifying those at risk of lower recovery.Clinical trial registration:ClinicalTrials.gov, identifier [NCT01622205]. Registered on June 19, 2012 (retrospectively registered).

Effect of very early supported discharge versus usual care on activi-ties of daily living ability after mild stroke: a randomized controlled trial.

OBJECTIVE: To examine the ability to perform basic and instrumental activities of daily life after very early supported discharge vs usual discharge and referral routine during the first year after mild stroke. DESIGN: A secondary analysis of data from the Gothenburg Very Early Supported Discharge randomized controlled trial.  Patients: A total of 104 patients (56% men; mean (standard deviation) age 75 (11) years) who had experienced a first stroke classified as mild. METHODS: The primary outcome was the Activities of Daily Living Taxonomy score. Stroke Impact Scale (activities of daily living, and mobility) scores was a secondary measure. Patients were randomized to either very early supported discharge with 4 weeks of home rehabilitation provided by a multidisciplinary stroke team, or a control group discharged according to usual routine (referral to primary care when needed). Assessments were performed at discharge, 4 weeks post-discharge, and 3 and 12 months post-stroke. RESULTS: Instrumental activities of the Activities of Daily Living Taxonomy scores (the lower the better) in the very early supported discharge and control groups were median 4 and 6 (p = 0.039) at 4 weeks post-discharge and 3 and 4.5 (p = 0.013 at 3 months post-stroke, respectively. Stroke Impact Scale (Mobility) median scores (the higher the better) in the very early supported discharge and control groups at 3 months were 97 and 86 (p = 0.040), respectively. There were no group differences in the 2 outcomes at 12 months post-stroke. CONCLUSION: Compared with usual discharge routine, team-based rehabilitation during the first month at home is beneficial for instrumental activity in the subacute phase, in patients with mild stroke. One year post-stroke both groups show equal results.

Patient-centered goal setting in very early supported discharge with continued rehabilitation after stroke.

PURPOSE: To examine patients' perception of performance and satisfaction with the activities in their set goals before and after very early supported discharge (VESD) with continued rehabilitation. MATERIALS AND METHODS: A descriptive cohort study with data extracted from a randomized controlled trial. Sixty-nine patient allocated to the intervention group were eligible. Before discharge, the patients were asked to set rehabilitation goals, and they were asked to rate the performance and satisfaction of their set goals. At discharge from the rehabilitation, the patients were asked to re-evaluate their experience and satisfaction with the goal performance. RESULTS: One hundred and forty goals were registered. At 81.5% of the set goals, the patients estimated that they performed the task better at discharge than at enrolment and at 86.5% of the set goals the patients were more satisfied with the performance at discharge than at enrolment. CONCLUSIONS: Patients with mild to moderate stroke, undergoing a VESD after stroke, reported high performance level for their set goals and were satisfied with their performance execution. Further research is needed to investigate whether the goal should be set preferably at home or at hospital before discharge.Implications for rehabilitationMany of the patients can formulate achievable goals with their rehabilitation after stroke.Patients ongoing rehabilitation after stroke are satisfied with their performance of the set goals.As part of patient-centered care, stroke patients should be given the opportunity to formulate their own goals with their rehabilitation.Short hospital times and fast planning of goal-meetings, seems to influence patient goal setting in early discharge rehabilitation.

A cohort study on longitudinal changes in postural balance during the first year after stroke.

INTRODUCTION: Many patients with strokes report increased incidence of fall that can be due to impaired postural balance. The recovery of balance in patients with varying degrees of impairments and activity limitations is less studied, and whether individuals with mild paresis can recover their balance faster is unclear. Better knowledge about factors influencing the recovery of postural balance can be used to guide clinical management after stroke to provide the right rehabilitation to the right person at the right time, and thus to avoid potential fall incidences. OBJECTIVE: This study aims to examine longitudinal changes in postural balance during the first year after stroke. METHODS: Postural balance was assessed using the Berg Balance Scale (BBS) within 5 days, 1, 2, and 3 months and 1-year post-stroke. Stroke severity was stratified using a cluster analysis by including multidimensional baseline measures. A longitudinal mixed-effect model was constructed to analyze changes in proportional balance impairment by stroke severity over time. Individuals with a cut-off of BBS below 45 scores were identified through a classification algorithm using baseline predictors. RESULTS: A total of 135 patients were stratified to mild stroke (77 [57%] patients) or moderate stroke (58 [43%] patients). Ninety-three patients were included in the longitudinal analysis. Significant recovery was found at 1-year for moderate stroke (48% recovery from the initial impaired postural balance, adjusted P < 0.001), but not for mild stroke, after adjusting for age and cognition. Both stroke severities had a maximal recovery in postural balance at 3 months post-stroke, but the moderate stroke group deteriorated after that. Patients with higher age and worse cognition had more severe balance impairments. The classification model achieved a sensitivity of 0.95 (95% confidence interval [CI]: 0.91-0.98) and a specificity of 0.99 (95% CI: 0.98-1.0) for classifying individuals with BBS below 45 points. CONCLUSIONS: This study indicates that continuous improvements in postural balance ends at 3 months regardless for mild or moderate stroke groups, and patients with moderate stroke significantly deteriorate in postural balance after 3 months.

Dependency in Activities of Daily Living During the First Year After Stroke.

Background: Dependency in personal activities of daily living (ADL) is a common short-term and long-term consequence of stroke and requires targeted rehabilitation. As the duration of hospital stay has become shorter in recent decades, early identification of patients who require rehabilitation has become vital. To our knowledge, no study has investigated whether ADL dependency in the very early stages after admission to the stroke unit can explain ADL dependency 3 and 12 months later. This knowledge would facilitate planning for very early discharge and patient-centered rehabilitation. Objective: This study evaluated whether ADL dependency within 2 days after stroke could explain ADL dependency at 3 and 12 months after stroke. Methods: This longitudinal cohort study included patients with stroke who were treated at a stroke unit in the Sahlgrenska University Hospital (Gothenburg, Sweden) between May 2011 and March 2016. The primary independent variable was ADL dependency at 36-48 h after admission to the stroke unit, which was assessed using a Barthel Index (BI) score of ≤90. The dependent variables were self-reported personal ADL dependency at 3 and 12 months after stroke. Binary logistic regression analyses were performed. Results: Of 366 eligible patients (58% male; median age 71 years), a majority (76%) had mild stroke and 60% were ADL dependent 36-48 h after stroke. Univariable and multivariable logistic regression analyses showed that patients who were dependent within the first 2 days after stroke had higher odds for being dependent 3 months as well as 12 months after stroke. Conclusion: The results indicated that dependency in personal ADL during the first 2 days can explain dependency at 3- and 12-month post-stroke. Therefore, early ADL assessments post-stroke can be used for understanding rehabilitation needs after stroke.

A prospective cohort study on longitudinal trajectories of cognitive function after stroke.

The study aimed to determine longitudinal trajectories of cognitive function during the first year after stroke. The Montreal Cognitive Assessment (MoCA) was used to screen cognitive function at 36-48 h, 3-months, and 12-months post-stroke. Individuals who shared similar trajectories were classified by applying the group-based trajectory models. Data from 94 patients were included in the analysis. Three cognitive functioning groups were identified by the trajectory models: high [14 patients (15%)], medium [58 (62%)] and low [22 (23%)]. For the high and medium groups, cognitive function improved at 12 months, but this did not occur in the low group. After age, sex and education matching to the normative MoCA from the Swedish population, 52 patients (55%) were found to be cognitively impaired at baseline, and few patients had recovered at 12 months. The impact on memory differs between cognitive functioning groups, whereas the impact on activities of daily living was not different. Patients with the poorest cognitive function did not improve at one-year poststroke and were prone to severe memory problems. These findings may help to increase focus on long-term rehabilitation plans for those patients, and more accurately assess their needs and difficulties experienced in daily living.

Self-perceived postural balance correlates with postural balance and anxiety during the first year after stroke: a part of the randomized controlled GOTVED study.

BACKGROUND: Postural balance is an important rehabilitation outcome, and screening stroke patients for confidence in postural balance during rehabilitation and before hospital discharge is recommended. Early supported discharge could improve postural balance self-confidence. This study aimed to investigate associations between patient self-confidence in postural balance and observer-assessed postural balance and anxiety during the first year after stroke. Whether very early supported discharge (VESD) affects self-confidence in postural balance compared with standard discharge was also evaluated. METHODS: A longitudinal trial for with data extracted from a randomized controlled study of 140 adults with confirmed stroke was conducted. The experimental group received VESD. The control group was discharged according to the standard routine. Postural balance was assessed with Berg Balance Scale (BBS), Timed Up and Go (TUG) test, and Falls Efficacy Scale. Anxiety was assessed with the Hospital Anxiety and Depression Scale. Spearman's rank correlation coefficient (rho) was used to test associations between independent variables. The Wilcoxon signed-rank test was used to examine differences over time. A single test, according to Eid, Gollwitzer, and Schmidt, was used to test temporal differences in correlation. RESULTS: The correlation between self-confidence in postural balance and observer-assessed postural balance was 0.62-0.78 in the first year after stroke. The correlation between self-confidence and anxiety was 0.22-0.41 in the first year after stroke. Correlations did not differ by group affiliation at any time point when the postural balance was assessed with BBS. The intervention group had a significantly higher correlation (r = - 0.709) than the control group (r = - 0.416) when postural balance was assessed with the TUG test 1 month after discharge. There were no significant differences in correlations between confidence in postural balance and anxiety between the two groups at any time point. CONCLUSIONS: Patients with mild stroke can accurately assess their confidence in performing daily activities without falling. VESD does not substantially affect the correlation between self-confidence in postural balance and observer assessed postural balance and is safe to use as an alternative to standard discharge. Assessment of self-confidence can provide important information for rehabilitation planning and supporting the physical activity of patients after discharge. TRIAL REGISTRATION: Clinical Trials.gov: NCT01622205 . Registered 19 June 2012 (retrospectively registered).

Predicting Longitudinal Progression in Functional Mobility After Stroke: A Prospective Cohort Study.

BACKGROUND AND PURPOSE: A majority of people with stroke remain impaired in their functional mobility. The aim of the study was to determine longitudinal changes in functional mobility after stroke. METHODS: The study was of a longitudinal and prospective design. The functional mobility was assessed using the Timed Up-and-Go test on 5 different occasions: 5 days after onset, within 24 hours after discharge, 1 month after discharge, 3 months, and 1 year poststroke. Stroke severity was stratified based on impairments and activity limitations using a baseline cluster analysis. A multilevel model was developed to predict longitudinal progression in functional mobility based on stroke severity. RESULTS: One-hundred-thirty-five patients were included at baseline. Two distinct subgroups (moderate stroke [52%] and mild stroke [48%]) were identified based on impairments and activity limitations using clustering. Ninety-one patients were included in the longitudinal analysis. After controlling for age and cognition, significant improvements in functional mobility were found in the moderate stroke group between baseline and 1 year poststroke (mean difference in Timed Up-and-Go test time, -6.4 s, adjusted P<0.001). Patients with moderate stroke had a maximum rate of improvement in functional mobility during the first 3 months poststroke and then declined significantly at 1 year (12% increase in Timed Up-and-Go test time, adjusted P=0.025). Younger patients had better functional mobility. Although there was also a slight improvement in the mild stroke group, it was not statistically significant. CONCLUSIONS: The recovery of functional mobility differs between mild and moderate stroke. Patients with moderate stroke improved their functional mobility during the first 3 months, after which it decreased significantly. These findings suggest that long-term rehabilitation is desirable to maintain and perhaps increase the gained functional mobility. Older patients and those with moderate impairments and activity limitations have particular needs. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01622205.

Very Early MoCA Can Predict Functional Dependence at 3 Months After Stroke: A Longitudinal, Cohort Study.

Introduction: After a stroke, cognitive impairment is commonly associated with poor functional outcomes. The primary aim of this study was to investigate if cognitive function, assessed with the Montreal Cognitive Assessment (MoCA) 36-48 h after stroke, could predict functional dependence 3 months later. The secondary aim was to identify an optimal threshold for the MoCA score that could predict functional dependence. Materials and Methods: This was a longitudinal cohort study. The research database from a stroke unit at the Sahlgrenska University Hospital was linked with the Swedish Stroke Register-Riksstroke. Cognitive function and activities of daily living (ADL) were assessed with the MoCA and the Barthel Index (BI), respectively, 36-48 h after stroke. Functional outcome 3 months after stroke was studied with the modified Rankin Scale. The predictive characteristics of the MoCA were investigated using logistic regression analyses. Receiver operating characteristic curves (AUC) were used for identifying the optimal cutoff score on the MoCA for predicting functional dependence. The MoCA score that had equal sensitivity and specificity was chosen as the optimal score for predicting functional dependence. Results: A total of 305 participants were included in the study (mean age: 68.8 years, n = 179 men). The MoCA quartiles were a significant predictor of functional dependence 3 months after stroke as an individual variable (p < 0.001, AUC = 0.72) and when adjusted for covariates such as age at stroke onset, living arrangement prior to stroke, and ADL measured with BI within 36-48 h after stroke (p = 0.01, AUC = 0.84). The MoCA score of ≤23 for impaired cognition had equal sensitivity and specificity for predicting functional dependence 3 months after stroke. Discussion and Conclusion: Cognitive function assessed with the MoCA within 36-48 h after stroke could predict functional dependence 3 months later. The participants with MoCA scores ≤23 for impaired cognition were more likely to be functionally dependent.

Gothenburg Very Early Supported Discharge study (GOTVED): a randomised controlled trial investigating anxiety and overall disability in the first year after stroke.

BACKGROUND AND PURPOSE: Early supported discharge (ESD) has been shown to be efficient and safe as part of the stroke care pathway. The best results have been seen with a multidisciplinary team and after mild to moderate stroke. However, how very early supported discharge (VESD) works has not been studied. The aim of this study was to investigate whether VESD for stroke patients in need of ongoing individualized rehabilitation affects the level of anxiety and overall disability for the patient compared with ordinary discharge routine. METHODS: A randomized controlled trial was performed with intention to treat analyses comparing VESD and ordinary discharge from hospital. All patients admitted at the stroke care unit at Sahlgrenska University Hospital of Gothenburg between August 2011 and April 2016 were screened. Inclusion occurred on day 4 using a block randomization of 20 and with a blinded assessor. Assessments were made 5 days post-stroke and 3 and 12 months post-stroke. Patients in the VESD group underwent continued rehabilitation in their homes with a multidisciplinary team from the stroke care unit for a maximum of 1 month. The patients in the control group had support as usual after discharge when needed such as home care service and outpatient rehabilitation. The primary outcome was anxiety as assessed by the Hospital Anxiety and Depression Scale-Anxiety subscale (HADS-A). The secondary outcome was the patients' degree of overall disability, measured by the modified Rankin Scale (mRS). RESULTS: No significant differences were found between the groups regarding anxiety at three or 12 months post-stroke (p = 0.811). The overall disability was significantly lower in the VESD group 3 months post-stroke (p = 0.004), compared to the control group. However, there was no significant difference between the groups 1 year post-stroke. CONCLUSIONS: The VESD does not affects the level of anxiety compared to ordinary rehabilitation. The VESD leads to a faster improvement of overall disability compared to ordinary rehabilitation. We suggest considering coordinated VESD for patients with mild to moderate stroke in addition to ordinary rehabilitation as part of the service from a stroke unit. TRIAL REGISTRATION: Clinical Trials.gov: NCT01622205. Registered 19 June 2012 (retrospectively registered).

Impaired Motor Function in the Affected Arm Predicts Impaired Postural Balance After Stroke: A Cross Sectional Study.

Background: Impaired postural balance is a common symptom after stroke and a common cause of falling. Most common daily tasks use arm and hand movements. Impairment in an upper extremity is a common stroke symptom, affecting 50-80% in the acute phase after stroke, and 40-50% in the sub-acute phase. The impact of leg function on postural balance has been investigated in several studies, but few have stressed the importance of arm function on postural balance. Objective: To explore whether there is any association between arm function and postural balance after stroke. Method: A cross sectional study where 121 adults (mean age: 70 ± 12.3 years, 72 men) from two different data sources, Gothenburg Very Early Supported Discharge (GOTVED), and a study by Carvalho et al. were merged. Time for assessments ranged from 1 to 13 years when the patients were in the chronic phase. The dependent variables were Berg Balance scale (BBS) and Time Up and Go (TUG) both dichotomized to "impaired postural balance" and "not impaired postural balance." As independent variables, the Fugl-Meyer Assessment-Upper Extremity (FMA-UE) scale was used. The FMA-UE was presented with the total score. Results: The motor function in the arm affected after stroke onset correlated with postural balance both measured with the BBS (0.321, p < 0.001) and the TUG (-0.315, p = 0.001). Having impaired motor function in the arm was significantly associated with impaired postural balance assessed with the BBS with OR = 0.879 (CI 0.826-0.934, p < 0.001). Regression analysis with the TUG showed the same result, OR = 0.868 (CI 0.813-0.927, p < 0.001) for FM-UE. Conclusion: The motor function of the affected arm was significantly associated with impaired postural balance post stroke, as assessed by BBS or TUG. It could be of clinical importance to be aware of the fact that not only lower extremity impairment, but also arm function can have an impact on postural balance in a late stage after stroke. Trial Registration: VGFOUGSB-669501.

Very early cognitive screening and return to work after stroke.

Background: Stroke is a common cause of long-term disability worldwide, and an increasing number of persons affected by stroke are of working age. In addition to physical impairments, a majority of patients reportedly suffer cognitive impairments after stroke. Reduced cognitive function may hinder poststroke return to work (RTW); however, most studies of this relationship have assessed cognitive function months after the stroke.Objectives: The current study aims to investigate the degree of post-stroke RTW, and whether very early cognitive function screening can predict RTW after a stroke.Methods: This study included 145 persons treated for stroke at 18-63 years of age at a large university hospital in Sweden between 2011 and 2016. Data were retrieved from the GOTVED database. Within 36-48 h after hospital admission, cognitive function was screened using the Montreal Cognitive Assessment (MoCA). Full and partial RTW were assessed based on the Swedish Social Insurance Agency's register. Logistic regression was performed to analyze the potential predictors of RTW at 6 months and 18 months.Results: Neither global cognitive function nor executive function at 36-48 h after stroke predicted any degree of RTW at 6 or 18 months. Male sex, lower stroke severity, and not being on sick leave prior to stroke were significant predictors of RTW.Conclusions: Screening for cognitive impairments at 36-48-h post stroke is apparently too early for predicting RTW, and thus cannot be the sole basis for discharge planning after stroke. Additional research is needed to further analyze cognitive function early after stroke and RTW.

Feasibility of Cognitive Functions Screened With the Montreal Cognitive Assessment in Determining ADL Dependence Early After Stroke.

Objective: To investigate the feasibility of assessing cognitive function using the Montreal Cognitive Assessment (MoCA) given 36-48 h post stroke to explain dependence in activities of daily living (ADL). Methods: This is a cross-sectional, exploratory study. Cognitive function and basic ADL were assessed with the MoCA and the Barthel Index (BI), respectively, within 36-48 h of admission. Neurological functions were assessed with the National Institute of Health Stroke Scale (NIHSS) upon admittance to the hospital. Binary logistic regression analyses were performed to assess the feasibility of the MoCA in explaining ADL dependence. Results: Data were available for 550 patients (42% females, mean age 69 years). Moderate correlations (rs > +0.30, p < 0.001) were found between the total score on the BI, MoCA, and visuospatial/executive functions. The regression analysis model including only MoCA as an independent variable had a high sensitivity for explaining ADL dependence. However, the model with independent variables of MoCA, NIHSS, and age had the best area under the curve value (0.74). Conclusions: Cognitive functions assessed with the MoCA partly explain ADL dependence 36-48 h post stroke. Stroke-related neurological deficits and age should be additional considerations.

Anxiety after stroke: A systematic review and meta-analysis.

OBJECTIVE: To update the evidence surrounding the presence of anxiety after stroke. DATA SOURCES: A search was conducted in EMBASE, MEDLINE, PsycINFO, Cochrane Library, AMED and CINAHL in May 2015 and repeated in April 2017. STUDY SELECTION: Clinical diagnosis of stroke and assessed for anxiety symptoms on a rating scale in the first year after stroke. DATA EXTRACTION: One reviewer screened and identified studies against the inclusion criteria. A second reviewer conducted a random check of approximately 10% of titles and abstracts. Two authors independently performed the final full-text review. DATA SYNTHESIS: Overall pooled prevalence of anxiety disorders was 29.3% ((95% confidence interval 24.8-33.8%), (I2 = 97%, p < 0.00001)) during the first year. Frequency 0-2 weeks post-stroke was 36.7%, 2 weeks to 3 months 24.1%, and 3-12 months 23.8%. There was a statistically high heterogeneity in this estimate (I2 = 97%, p < 0.00001). CONCLUSION: Anxiety is common during the first year post-stroke. Since anxiety significantly influences quality of life and is a predictor for depression, it may be worth considering further routine screening post-stroke.

Gothenburg very early supported discharge study (GOTVED) NCT01622205: a block randomized trial with superiority design of very early supported discharge for patients with stroke.

BACKGROUND: Stroke is the disease with the highest costs for hospital care and also after discharge. Early supported discharge (ESD) has shown to be efficient and safe and the best results with well-organised discharge teams and patients with less severe strokes. The aim is to investigate if very early supported discharge (VESD) for stroke patients in need for on-going individualised rehabilitation at home is useful for the patient and cost effective. METHODS/DESIGN: A randomized controlled trial comparing VESD with ordinary discharge. INCLUSION CRITERIA: confirmed stroke, >18 years of age, living within 30 min from the stroke unit, on day 2 0-16 points on the National institute of health stroke scale (NIHSS) and 50-100 points on the Barthel Index (BI), with BI 100 then the patient can be included if the Montreal Cognitive Assessment is < 26. Exclusion criteria are: NIHSS >16, BI < 50, life expectancy < 1 year, inability to speak or to communicate in Swedish. The inclusion occurs on day 4 and in block randomization of 20 and with blinded assessor. PRIMARY OUTCOME: levels of anxiety and depression. SECONDARY OUTCOMES: independence, security, level of function, quality of health, needs of support in activities of daily living and caregiver burden. Power calculation is based on the level of anxiety and with a power of 80%, p-value 0.05 (2 sided test) 44 persons per group are needed. Data is gathered on co-morbidity, re-entry to hospital, mortality and a health economic analysis. Interviews will be accomplished with a strategic sample of 15 patients in the intervention group before discharge, within two weeks after homecoming and 3 months later. Interviews are also planned with 15 relatives in the intervention group 3 months after discharge. DISCUSSION: The ESD studies in the Cochrane review present hospital stays of a length that no longer exist in Sweden. There is not yet, to our knowledge, any study of early supported discharge with present length of hospital stay. Thus it is not clear if home rehabilitation nowadays without risks, is cost effective, or with the same patient usefulness as earlier studies. TRIAL REGISTRATION: ClinicalTrials.gov NCT01622205.

Modified exercise test in screening for mitochondrial myopathies--adjustment of workload in relation to muscle strength.

The aim of this study was to evaluate the usefulness of a modification of the bicycle ergometer test, the subanaerobic threshold exercise test (SATET), as a screening test for patients with mitochondrial myopathies. Since the original SATET is frequently found to be strenuous for weak patients, a new variable (relative muscle strength) was added to the workload formula. Plasma lactate levels were recorded at rest, then after 5 and 15 min of cycling on an ergometer, with constant workload. Nine patients with mitochondrial myopathy, 10 patients with other neuromuscular diseases and 9 healthy but sedentary volunteers undertook the test. An upper reference limit after exercise for plasma lactate was settled at 2.9 mmol/l. The modified SATET showed a sensitivity of 78% and a specificity compared to the healthy subjects of 100%. Compared to patients with other neuromuscular diseases, the specificity was lower (60%). All subjects completed the test without severe fatigue or pain.