Disability and functional assessment in former polio patients with and without postpolio syndrome

Exercise therapy and cognitive behavioural therapy to improve fatigue, daily activity performance and quality of life in postpoliomyelitis syndrome: the protocol of the FACTS-2-PPS trial

Background

Postpoliomyelitis Syndrome (PPS) is a complex of late onset neuromuscular symptoms with new or increased muscle weakness and muscle fatigability as key symptoms. Main clinical complaints are severe fatigue, deterioration in functional abilities and health related quality of life. Rehabilitation management is the mainstay of treatment. Two different therapeutic interventions may be prescribed (1) exercise therapy or (2) cognitive behavioural therapy (CBT). However, the evidence on the effectiveness of both interventions is limited. The primary aim of the FACTS-2-PPS trial is to study the efficacy of exercise therapy and CBT for reducing fatigue and improving activities and quality of life in patients with PPS. Additionally, the working mechanisms, patients' and therapists' expectations of and experiences with both interventions and cost-effectiveness will be evaluated.

Methods/Design

A multi-centre, single-blinded, randomized controlled trial will be conducted. A sample of 81 severely fatigued patients with PPS will be recruited from 3 different university hospitals and their affiliate rehabilitation centres. Patients will be randomized to one of three groups i.e. (1) exercise therapy + usual care, (2) CBT + usual care, (3) usual care. At baseline, immediately post-intervention and at 3- and 6-months follow-up, fatigue, activities, quality of life and secondary outcomes will be assessed. Costs will be based on a cost questionnaire, and statistical analyses on GEE (generalized estimated equations). Analysis will also consider mechanisms of change during therapy. A responsive evaluation will be conducted to monitor the implementation process and to investigate the perspectives of patients and therapists on both interventions.

Discussion

A major strength of the FACTS-2-PPS study is the use of a mixed methods design in which a responsive and economic evaluation runs parallel to the trial. The results of this study will generate new evidence for the rehabilitation treatment of persons with PPS.

Trial registration

Dutch Trial Register NTR1371.

Changes in ability, perceived difficulty and use of assistive devices in everyday life: a 4-year follow-up study in people with late effects of polio

BACKGROUND

There are numbers of persons living in the community with late effects of polio, of which many develop new symptoms, but the course of progression is unclear.

OBJECTIVES

To assess changes after 4 years in ability and perceived difficulty in persons with late effects of polio.

MATERIAL AND METHODS

Community dwelling persons from a polio clinic. Information was gathered by questionnaire and interview on demographics, age at polio onset, affected body parts, health problems, the use of assistive devices, housing condition and activities of daily living (ADL) function as well as perceived difficulties.

RESULTS

There were no significant increase in frequency of ADL dependency but perceived difficulties increased significantly and more used mobility devices.

CONCLUSIONS

Over 4 years, more persons perceived difficulties and the use of assistive devices increased. This is might reflect adaptation and acknowledgement of problems previously ignored. Time is a factor in integrating knowledge and adaptation.

Alzheimer's disease-associated disability: An ICF approach

PURPOSE

The aim of the study is to provide a description of dementia-associated disability in Alzheimer's disease (AD) patients through the International Classification of Functioning, Disability and Health (ICF).

METHOD

Twenty-six AD patients at different stages of disease participated in the study. Mini Mental State Examination (MMSE) and Global Deterioration Scale (GDS) were used to stage the degree of cognitive impairment and the stage of disease, respectively. All subjects were classified using the ICF categories in the more detailed four-level version. Correlation between compromised ICF items and both MMSE and GDS scores were calculated through Spearman Rho test.

RESULTS

Mental functions were impaired in all the subjects examined. Data on activity and participation showed that not only domestic life, self care, and mobility but also communication and interaction and social relationships are compromised in AD patients. Three main areas appeared as the most relevant facilitators: products and technology, support and relationship and services, systems and policies. ICF codes were generally correlated with both MMSE and GDS: subjects who appeared more compromised on MMSE and GDS showed higher impairment of functions, activity limitation, and participation restriction.Conclusion. ICF is a useful tool to describe health status in AD patients in that it underlines important aspects of daily living generally not considered by activity of daily living scales such as communication, social relationships, and recreation and leisure.

Fear of falling, balance confidence and health-related quality of life in individuals with postpolio syndrome

The purposes of this study were to examine prevalence of fear of falling (FOF) and decreased balance confidence in individuals with postpolio syndrome (PPS) and to determine whether balance confidence was correlated with health-related quality of life (HRQOL) in this population. A survey, which included demographic questions, the Activities-specific Balance Confidence (ABC) Scale, and the MOS SF-36v2, was made available by mail and electronically to individuals with PPS. Descriptive and correlation statistics were used to analyze the responses. Fear of falling was reported in 95% of respondents, with 80% indicating that FOF affected their quality of life. Median ABC score (42 of 100), physical component score (27 of 100), and mental component score (47 of 100) were below average compared with the general population. A moderate correlation (r = 0.4; p < 0.001) was found between balance confidence and the physical component score of HRQOL in PPS. There was an overwhelming presence of FOF and severely impaired balance confidence in the majority of those with PPS. A fair correlation between the physical functioning component of HRQOL and balance confidence was noted in this population.

Prolonged benefit in post-polio syndrome from comprehensive rehabilitation: a pilot study

PURPOSE

To report physical, psychological and functional outcomes from a pilot study of a multi-disciplinary rehabilitation programme for post-polio syndrome (PPS).

METHOD

Twenty-seven participants completed the nine-day programme and were available for re-assessment at three and six months. Physical outcome measures were muscle strength and endurance; psychological outcomes included illness perceptions (IPQ), depression and anxiety (HADS); functional outcomes were fatigue (HFS) and client-centred occupational performance and satisfaction (COPM).

RESULTS

There was no significant change at six months for muscle strength or anxiety. Significant improvements were recorded for exercise endurance, depression and levels of fatigue. A shift towards an endorsement that the patient's own behaviour could be important in symptom severity of PPS was seen. Five out of 24 participants demonstrated significant clinical changes in occupational performance and satisfaction on the COPM.

CONCLUSIONS

Prolonged benefits were found for physical, psychological and functional outcomes. A qualitative study is planned to investigate the patient-reported benefits of attending the programme such as the support gained interacting with others with similar disability and in lifestyle adjustment such as pacing of physical activities.

Short-term effects of aerobic exercise on functional capacity, fatigue, and quality of life in patients with post-polio syndrome

OBJECTIVE

To investigate and compare the impact of hospital and home exercise programmes on aerobic capacity, fatigue, and quality of life in patients with post-polio syndrome.

DESIGN

A prospective, randomized controlled trial.

SETTING

Department of Physical Medicine and Rehabilitation, University Hospital.

SUBJECTS

Thirty-two patients were divided into two groups for either hospital- or home-based aerobic exercise programme.

MAIN OUTCOME MEASURES

Patients were assessed before and after the rehabilitation programme, with respect to functional capacity (pVo2), fatigue (Fatigue Severity Scale, Fatigue Impact Scale) and quality of life (Nottingham Heath Profile).

RESULTS

After the exercise programme, improvement was observed in the hospital exercise group compared to a pre-exercise period in all Nottingham Heath Profile scores (except sleep scores), pVo2, Fatigue Severity Scale and Fatigue Impact Scale (cognitive, physical, psychosocial, total) (P<0.05). In contrast, in the home exercise group a decrease was observed in pVo2 scores after the rehabilitation programme, compared to a pre-rehabilitation period (P<0.05). In addition, a significant improvement was observed in the home exercise group after the rehabilitation programme in all parameters excluding Fatigue Impact Scale-physical, Fatigue Impact Scale-psychosocial, and Nottingham Heath Profile-sleep (P<0.05). When the two exercise groups were compared, improvement was observed in the hospital exercise group compared to the home exercise group in pVo2 and Fatigue Severity Scale-total, Fatigue Impact Scale-physical, Fatigue Impact Scale-psychosocial, Fatigue Impact Scale-total, and Nottingham Heath Profile-energy scores (P<0.05).

CONCLUSION

Fatigue and quality of life were both improved in the home and hospital exercise groups. An increase was also found in the functional capacity in the hospital exercise group. A regular exercise programme is beneficial to patients with post-polio syndrome.

In vivo 31P MRS study of skeletal muscle metabolism in patients with postpolio residual paralysis

The muscle metabolism of at-rest patients with varying degrees of postpolio residual paralysis (PPRP) was studied and compared with that of controls using in vivo phosphorus magnetic resonance spectroscopy. The phosphocreatine (PCr)/inorganic phosphate (Pi) and PCr/adenosine triphosphate ratios were lower in patients than in controls. Reduction in PCr/Pi suggests abnormalities in oxidative phosphorylation. A significant increase was observed in the phosphomonoester/PCr ratio in patients, indicating the accumulation of intermediary compounds of the glycolytic pathway. Furthermore, the phosphodiester/PCr ratio was also significantly increased in patients. In general, the observed changes in metabolite ratios were found to be related to the degree of residual paralysis, suggesting that metabolic changes are secondary to chronic neurogenic processes. These metabolic alterations appear to be the possible cause of energy deficit and underlying muscle fatigue in PPRP patients. The present results provide an insight into the metabolic impairment and degree of muscle damage in patients with PPRP.

Perceived disability, fatigue, pain and measured isometric muscle strength in patients with post-polio symptoms

BACKGROUND AND PURPOSE

Several years after the acute polio illness, patients may develop new post-polio symptoms. The purpose of the present study was to evaluate patients with post-polio symptoms with regard to perceived fatigue, functional ability, muscle strength, pain and with regard to measured physical fitness and isometric muscle strength. In addition, the relationship between the results of these subjective and objective measurements was investigated.

METHOD

This was a prospective cross-sectional study in which 32 patients with post-polio symptoms were included. Main outcome measures were the Fatigue Severity Scale (FSS), the Disability Rating Index (DRI), pain intensity, pain distribution, self-reported and measured muscle strength and oxygen uptake.

RESULTS

A marked reduction in isometric muscle strength compared to normal data, high scores in fatigue, widespread pain, low oxygen uptake and difficulties in performing some daily activities were found. Self-reported general muscle strength, pain intensity and pain distribution correlated significantly with patients' perceived fatigue and function at the activity level. There was no significant correlation between self-reported and measured results except for that found between isometric muscle strength in the legs and patients' perceived general muscle strength and oxygen uptake.

CONCLUSIONS

Evaluation of pain intensity, pain distribution, perceived muscle strength, fatigue and ability to perform daily tasks reveals important aspects of health status in patients with post-polio symptoms. Reduction in isometric muscle strength was not reflected in those tests or in reported symptoms, and should be monitored independently using a sensitive assessment tool. Accurate screening of isometric muscle strength in isolated muscle groups contributes to therapeutic management in making a functional diagnosis at the level of body function and structure when designing specific training programmes and in motivating patients. An evaluation combining self-reports with sensitive muscle strength measures provide supplementary information and is appropriate for evaluating these patients in physiotherapy practice.

EFNS guideline on diagnosis and management of post-polio syndrome. Report of an EFNS task force

Post-polio syndrome (PPS) is characterized by new or increased muscular weakness, atrophy, muscle pain and fatigue several years after acute polio. The aim of the article is to prepare diagnostic criteria for PPS, and to evaluate the existing evidence for therapeutic interventions. The Medline, EMBASE and ISI databases were searched. Consensus in the group was reached after discussion by e-mail. We recommend Halstead's definition of PPS from 1991 as diagnostic criteria. Supervised, aerobic muscular training, both isokinetic and isometric, is a safe and effective way to prevent further decline for patients with moderate weakness (Level B). Muscular training can also improve muscular fatigue, muscle weakness and pain. Training in a warm climate and non-swimming water exercises are particularly useful (Level B). Respiratory muscle training can improve pulmonary function. Recognition of respiratory impairment and early introduction of non-invasive ventilatory aids prevent or delay further respiratory decline and the need for invasive respiratory aid (Level C). Group training, regular follow-up and patient education are useful for the patients' mental status and well-being. Weight loss, adjustment and introduction of properly fitted assistive devices should be considered (good practice points). A small number of controlled studies of potential-specific treatments for PPS have been completed, but no definitive therapeutic effect has been reported for the agents evaluated (pyridostigmine, corticosteroids, amantadine). Future randomized trials should particularly address the treatment of pain, which is commonly reported by PPS patients. There is also a need for studies evaluating the long-term effects of muscular training.

The Relation Between Walking Capacity and Clinical Correlates in Survivors of Chronic Spinal Poliomyelitis

OBJECTIVES

To examine (1) common clinical measures that may influence walking performance in the six-minute walk test (6MWT) in people with chronic poliomyelitis and (2) the test-retest reliability of the 6MWT distance, lower-extremity muscle strength, balance, and balance confidence on separate trials.

DESIGN

A prospective quasi-experimental study.

SETTING

University-based postpolio clinic.

PARTICIPANTS

Nineteen survivors of poliomyelitis (mean age, 62.2+/-1.9y; time since polio onset, 54.4+/-8.79y).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

6MWT distance, rate-pressure product (RPP), Physiological Cost Index (PCI), ratings of perceived exertion (RPE), pain, fatigue, strength, standing balance, balance confidence, limb-length discrepancy, and lung function.

RESULTS

The 6MWT distance correlated with PCI, pretest pain, lower-extremity muscle strength, balance, balance confidence, corrected leg-length discrepancy, and lung function but not with RPP, RPE, posttest pain, or pretest and posttest fatigue. The PCI correlated with balance confidence and lung function. About 68% of the variance in 6MWT distance was accounted for by balance and pretest pain. The P value was set at .05.

CONCLUSIONS

With stringent standardization of the 6MWT applied to survivors of poliomyelitis (a neuromuscular condition with a musculoskeletal component), reproducibility was high; hence, test validity and interpretation were enhanced. The 6MWT distance was useful in elucidating the relation between impairment and a functional activity-namely, walking-in survivors of poliomyelitis.

Fatigue and neuromuscular diseases

PURPOSE

To identify the role of fatigue, its evaluation and its causes in the pathophysiology context of acquired or hereditary neuromuscular diseases of the spinal anterior horn cell, peripheral nerve, neuromuscular junction and muscle.

MATERIAL AND METHODS

A literature review has been done on Medline with the following keywords: neuromuscular disease, peripheral neuropathy, myopathy, fatigue assessment, exercise intolerance, force assessment, fatigue scale and questionnaire, then with the terms: Fatigue Severity Scale, Chalder Fatigue Scale, Fatigue Questionnaire, Piper Fatigue Scale, electromyography and the combination of the word Fatigue with the following terms: Amyotrophic Lateral Sclerosis (ALS), Post-Polio Syndrome (PPS), Guillain-Barre Syndrome, Immune Neuropathy, Charcot-Marie-Tooth Disease, Myasthenia Gravis (MG), Metabolic Myopathy, Mitochondrial Myopathy, Muscular Dystrophy, Facioscapulohumeral Dystrophy, Myotonic Dystrophy.

RESULTS

Fatigue is a symptom very frequently reported by patients. Fatigue is mainly evaluated by strength loss after an exercise, by change in electromyographic activity during a given exercise and by questionnaires that takes into account the subjective (psychological) part of fatigue. Due to the large diversity of motor disorders, there are multiple clinical expressions of fatigue that differ in their presentation, consequences and therapeutic approach.

CONCLUSION

This review shows that fatigue has to be taken into account in patients with neuromuscular diseases. In this context, pathophysiology of fatigue often implies the motor component but the disease evolution and the physical obligates of daily life also induce an important psychological component.

Fatigue of muscles weakened by death of motoneurons

Weakness is a characteristic of muscles influenced by the postpolio syndrome (PPS), amyotrophic lateral sclerosis (ALS), and spinal cord injury (SCI). The strength deficits relate to changes in muscle use and to the chronic denervation that can follow the spinal motoneuron death common to these disorders. PPS, ALS, and SCI also involve variable amounts of supraspinal neuron death, the effects of which on muscle weakness remains unclear. Nevertheless, weakness of muscle itself defines the functional consequences of these disorders. A weaker muscle requires an individual to work that muscle at higher than usual intensities relative to its maximal capacity, inducing progressive fatigue and an increased sense of effort. Little evidence is available to suggest that the fatigue commonly experienced by individuals with these disorders relates to an increase in the intrinsic fatigability of the muscle fibers. The only exception is when SCI induces chronic muscle paralysis. To reduce long-term functional deficits in these disorders, studies must identify the signaling pathways that influence neuron survival and determine the factors that encourage and limit sprouting of motor axons. This may ensure that a greater proportion of the fibers in each muscle remain innervated and available for use.

Strength and endurance of knee extensors in subjects after paralytic poliomyelitis

PURPOSE

To compare the strength and endurance of knee extensors in subjects after paralytic poliomyelitis as well as to extend the comparison to healthy subjects.

METHOD

Twenty subjects after poliomyelitis with new symptoms (SYM group), 10 without new symptoms (ASYM group) and 15 healthy controls were included. To determine strength, isometric maximal voluntary contraction (MVC) torque of knee extensors in both legs was determined by Biodex dynamometer at 60 degrees knee angle. To determine endurance, the subjects were asked to maintain force in the knee extensors in the same position, in the range between 40-45% of MVC torque, as long as possible. The 'tensiomyography' method was applied to measure the radial displacement of m. rectus femoris during submaximal continuous electrical stimulation until recording a flat response.

RESULTS

No significant difference in MVC torque and endurance was found between SYM and ASYM group, as well between the duration of m. rectus femoris response of both groups to submaximal electrical stimulation. MVC torque and endurance of knee extensors with 'normal' strength was significantly lower in post-polio subjects compared to healthy controls.

CONCLUSION

Endurance of knee extensor muscles in post-polio subjects is generally and significantly lower than that of knee extensors in healthy subjects, regardless of the implication of normal strength and subjective observations of post-polio subjects.

Energy Demands of Walking in Persons With Postpoliomyelitis Syndrome: Relationship With Muscle Strength and Reproducibility

OBJECTIVES

To describe the energy demands of walking in subjects with postpoliomyelitis syndrome (PPS) in comparison with the demands in healthy subjects, and to assess the reproducibility of walking energy measurements.

DESIGN

Four repeated measurements with a 1-week interval between each measurement.

SETTING

Outpatient clinic of a university hospital.

PARTICIPANTS

Fourteen subjects with PPS and 14 age- and sex-matched healthy subjects.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Walking speed and energy cost of walking. The correlation parameter was lower-extremity muscle strength sum (MSS). The reproducibility parameters were standard error (SE) of measurement and smallest detectable difference (SDD).

RESULTS

Walking speed in subjects with PPS (61.8 m/min) was significantly lower (-28%) and energy cost (4.8 J.kg(-1).m(-1)) was significantly higher (40%) than in healthy subjects. MSS correlated strongly with energy cost (r=-.84, P=.000), explaining 71% of the variance. The SE of measurement of energy cost measurements ranged between 1.7% and 3.4% for PPS subjects and between 1.2% and 2.4% for healthy subjects. The SDD ranged between 4.6% and 9.4% for PPS subjects and between 3.3% and 6.6% for healthy subjects, depending on the number of repeated measurements that were considered.

CONCLUSIONS

Energy cost of walking in subjects with PPS is strongly related to the extent of muscle weakness in the lower extremities. Although variability was greater for PPS subjects than for healthy subjects, reproducibility of energy cost measurements was high. Therefore, metabolic assessment of energy cost of walking is a sensitive tool that can reveal clinically relevant changes even in the condition of a person with PPS.

The Course of Functional Status and Muscle Strength in Patients With Late-Onset Sequelae of Poliomyelitis: A Systematic Review

OBJECTIVES

To review systematically studies of late-onset polio sequelae on the course of functional status and muscle strength over time and to identify prognostic factors of change.

DATA SOURCES

We conducted a computerized literature search up to July 2004 in MEDLINE, EMBASE, CINAHL, Web of Science, PsychInfo, and the Cochrane controlled trial register using the key words: postpolio, postpoliomyelitis, postpoliomyelitis syndrome, post poliomyelitis muscular atrophy, and poliomyelitis.

STUDY SELECTION

Reports were selected by 1 reviewer if the study involved subjects with a history of poliomyelitis, the outcome measures described functional status or muscle strength, and follow-up was for at least 6 months.

DATA EXTRACTION

Studies were summarized with regard to population, design, sample size, outcome measures, results, and methodologic scores. Overlap in populations between studies was checked.

DATA SYNTHESIS

Of 71 potentially relevant studies, 19 were included (2 on functional status, 15 on muscle strength, 2 on both muscle strength and functional status). Two studies on the course of functional status had sufficient quality and reported inconsistent results. Four studies on the course of muscle strength had sufficient quality. Two studies reported a decline in strength and 2 reported no change. Decline in strength was only reported in studies with a follow-up period longer than 2 years. One study reported extent of paresis as a prognostic factor for change in perceived physical mobility.

CONCLUSIONS

Conclusions cannot be drawn from the literature with regard to the functional course or prognostic factors in late-onset polio sequelae. The rate of decline in muscle strength is slow, and prognostic factors have not yet been identified. Long-term follow-up studies with unselected study populations and age-matched controls are needed, with specific focus on prognostic factors.

Walking in postpoliomyelitis syndrome: the relationships between time-scored tests, walking in daily life and perceived mobility problems

OBJECTIVE

To compare walking test results with walking in daily life, and to investigate the relationships between walking tests, walking activity in daily life, and perceived mobility problems in patients with post-poliomyelitis syndrome.

SUBJECTS

Twenty-four ambulant patients with post-poliomyelitis syndrome.

METHODS

Walking tests were performed at self-preferred and maximal speed. Walking activity was measured with an ambulatory activity monitor. Heart rate, step cadence and walking speed in the test and in daily life were compared. Walking speed in daily life was represented by the intensity of walking. Perceived mobility problems were assessed with the Nottingham Health Profile.

RESULTS

Heart rate during walking was lower in the test at self-preferred speed than in daily life (mean difference: 11.3+/-10.4; p=0.001). Self-preferred walking speed in the test and in daily life correlated significantly (r=0.55; p=0.04). In a sub-group with a test performance below the median value, test performance correlated significantly with walking activity. No significant correlation was found between perceived mobility problems and walking activity.

CONCLUSION

Walking in daily life may be more demanding than walking under standardized conditions. Patients with post-poliomyelitis syndrome with the lowest test performance walked less in daily life. Patients do not necessarily match their activity pattern to their perceived mobility problems.

Reproducibility of walking at self-preferred and maximal speed in patients with postpoliomyelitis syndrome

OBJECTIVE

To assess the reproducibility of walking performance, heart rate, and perceived exertion at self-preferred speed and maximal walking speed in patients with the postpoliomyelitis syndrome (PPS).

DESIGN

Repeated measurement at a 3-week interval.

SETTING

University hospital.

PARTICIPANTS

Convenience sample of 65 patients with PPS.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Walking performance: the distance walked in 2 minutes at a self-preferred speed and the time needed to walk 75 m at maximal speed, heart rate, and rating of perceived exertion (RPE) on an 11-point scale.

RESULTS

Test-retest reliability of walking performance was excellent for both tests (intraclass correlation coefficient [ICC] range, .94-.97). No systematic differences existed between test and retest. The smallest detectable change for an individual was 15% for both tests. Test-retest reliability for heart rate was good (ICC=.86) but moderate for RPE (Spearman rho range, .67-.70). The smallest detectable change for RPE was between 4 and 6 scale points. The variability in walking performance was significantly correlated with the variability in heart rate at self-preferred speed (r =.36, P <.01) but not with the variability in RPE (r =.20, P =.11).

CONCLUSIONS

Both walking tests showed good reproducibility and may be appropriate to monitor (individual) changes in walking capacity in patients with PPS. Because of its moderate reproducibility, RPE does not seem to be suitable to monitor physical exertion. The usefulness of an objective measure such as heart rate for this purpose needs further investigation.

Postpolio syndrome: a challenge to the health-care system

The practical eradication of poliomyelitis in industrialized countries marks one of the most important achievements of world health policy. Yet, disability induced by polio not only continues to exist among survivors with paralytic sequelae, but may also be further accentuated in a considerable number of affected subjects by the development of postpolio syndrome (PPS). PPS aggravates the motor sequelae already present in such subjects and reduces their functional capacity to the point where it affects their activities of daily living and worsens their quality of life. Inasmuch as development of PPS questions the concept of poliomyelitis as a static disease it poses a challenge not only to health professionals but also to policy-makers tasked with providing the necessary health-care measures and appropriate resources. This study sought to review research on this syndrome and to draw up some recommendations that might prove useful to the health authorities for decision-making purposes.

Measuring activity limitations in climbing stairs: development of a hierarchical scale for patients with lower-extremity disorders living at home11No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit on the author(s) or on any organization with which the author(s) is/are associated

OBJECTIVE

To develop a hierarchical scale that measures activity limitations in climbing stairs in patients with lower-extremity disorders living at home.

DESIGN

Cross-sectional study with Mokken scale analysis of 15 dichotomous items.

SETTING

Outpatient clinics of secondary and tertiary care centers.

PARTICIPANTS

Patients (N=759; mean age +/- standard deviation, 59.8+/-15.0y; 48% men) living at home, with different lower-extremity disorders: stroke, poliomyelitis, osteoarthritis, amputation, complex regional pain syndrome type I, and diabetic foot problems.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

(1) Fit of the monotone homogeneity model, indicating whether items can be used for measuring patients; (2) fit of the double monotonicity model, indicating invariant (hierarchical) item ordering; (3) intratest reliability, indicating repeatability of the sum score; and (4) differential item functioning, addressing the validity of comparisons between subgroups of patients.

RESULTS

There was (1) good fit of the monotone homogeneity model (coefficient H=.50) for all items for all patients, and for subgroups defined by age, gender, and diagnosis; (2) good fit of the double monotonicity model (coefficient H(T)=.58); (3) good intratest reliability (coefficient rho=.90); and (4) no differential item functioning with respect to age and gender, but differential item functioning for 4 items in amputees compared with nonamputees.

CONCLUSIONS

A hierarchical scale, with excellent scaling characteristics, has been developed for measuring activity limitations in climbing stairs in patients with lower-extremity disorders who live at home. However, measurements should be interpreted with caution when comparisons are made between patients with and without amputation.

A comparison of 4 questionnaires to measure fatigue in postpoliomyelitis syndrome

OBJECTIVE

To assess the comparability and reproducibility of 4 questionnaires used to measure fatigue in postpoliomyelitis syndrome (PPS).

DESIGN

Repeated-measures at a 3-week interval.

SETTING

University hospital.

PARTICIPANTS

Convenience sample of 65 patients with PPS.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The Fatigue Severity Scale (FSS), the Nottingham Health Profile (NHP) energy category, the Polio Problem List (PPL) fatigue item, and the Dutch Short Fatigue Questionnaire (SFQ).

RESULTS

Correlations of scores between questionnaires were all significant (P<.01) and ranged from.43 (between the NHP energy category and the PPL fatigue item) to.68 (between the PPL fatigue item and the SFQ). Scores on the second visit, normalized to a 0 to 100 scale, were: FSS, 78+/-15; NHP energy category, 47+/-35; PPL fatigue item, 81+/-17; and SFQ, 65+/-22. Except for the difference between the FSS and the PPL fatigue item, the differences in scores between the questionnaires were significant (P<.01). Scale analysis indicated that all questionnaires measured the same unidimensional construct. The reproducibility of the FSS, the PPL fatigue item, and the SFQ was moderate. The smallest detectable change was 1.5 points for the FSS, 2.0 points for the PPL fatigue item, and 1.9 points for the SFQ.

CONCLUSIONS

Although the questionnaires measure the same fatigue construct in PPS, the results are not interchangeable because the ranges of measurement differ. The NHP energy category, in particular, appeared to have a high detection threshold. The moderate reproducibility of the questionnaires indicates a lack of precision, especially when applied at the individual patient level.

Pyridostigmine in postpolio syndrome: no decline in fatigue and limited functional improvement

OBJECTIVES

To investigate the effect of pyridostigmine on fatigue, physical performance, and muscle function in subjects with postpoliomyelitis syndrome.

METHODS

67 subjects with increased fatigue and new weakness in one quadriceps muscle showing neuromuscular transmission defects, were included in a randomised, double blind, placebo controlled trial of 60 mg pyridostigmine four times a day for 14 weeks. Primary outcome was fatigue (on the "energy" category of the Nottingham health profile). Secondary outcomes included two minute walking distance and quadriceps strength and jitter. Motor unit size of the quadriceps was studied as a potential effect modifier. The primary data analysis compared the changes from baseline in the outcomes in the last week of treatment between groups.

RESULTS

31 subjects treated with pyridostigmine and 31 subjects treated with placebo completed the trial. No significant effect of pyridostigmine was found on fatigue. The walking distance improved more in the pyridostigmine group than in the placebo group (by 7.2 m (6.0%); p<0.01). Subgroup analysis showed that a significant improvement in walking performance was only found in subjects with normal sized motor units. Quadriceps strength improved more in the pyridostigmine group than in the placebo group (by 6.7 Nm (7.2%); p = 0.15). No effect of pyridostigmine was found on jitter.

CONCLUSIONS

Pyridostigmine in the prescribed dose did not reduce fatigue in subjects with postpoliomyelitis syndrome. However, it may have a limited beneficial effect on physical performance, especially in subjects with neuromuscular transmission defects in normal sized motor units.

Quadriceps muscle strength and voluntary activation after polio

Quadriceps strength, maximal anatomical cross-sectional area (CSA), maximal voluntary activation (MVA), and maximal relaxation rate (MRR) were studied in 48 subjects with a past history of polio, 26 with and 22 without postpoliomyelitis syndrome (PPS), and in 13 control subjects. It was also investigated whether, apart from CSA, MVA and MRR were determinants of muscle strength. Polio subjects had significantly less strength, CSA, and MRR in the more-affected quadriceps than control subjects. MVA was reduced in 18 polio subjects and normal in all controls. PPS subjects differed from non-PPS subjects only in that the MVA of the more-affected quadriceps was significantly lower. Both CSA and MVA were found to be associated with muscle strength. Quadriceps strength in polio subjects was dependent not only on muscle mass, but also on the ability to activate the muscles. Since impaired activation was more pronounced in PPS subjects, the new muscle weakness and functional decline in PPS may be due not only to a gradual loss of muscle fibers, but also to an increasing inability to activate the muscles.

Perceived health and physical functioning in postpoliomyelitis syndrome: a 6-year prospective follow-up study

OBJECTIVES

To study prospectively the health status, and especially the physical functioning, of polio survivors with and without postpoliomyelitis syndrome (PPS), and to identify prognostic determinants of change in physical functioning.

DESIGN

Prospective cohort study; measurements at baseline and after 1, 2, and 6 years.

SETTING

University hospital in the Netherlands.

PARTICIPANTS

Seventy-six subjects with PPS and 27 without PPS.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

The Nottingham Health Profile (NHP) physical mobility category.

RESULTS

Subjects with PPS had significantly poorer health status than subjects without PPS. No significant differences in mean NHP physical mobility scores between baseline and 6 years were found; both groups had improved after 1 year, after which there was a slow decline over the next 5 years. During the first 2 years, strength measurements showed little decline that was not related to changes in NHP physical mobility score. A physical performance test revealed no mean change in the first 2 years, but the subgroup with a decline above the 75th percentile eventually deteriorated 10.5+/-16.3 points on the NHP physical mobility category (P=.01) at 6 years from baseline. This subgroup had more extensive paresis than the other subjects, although it was not significant (P=.07). The extent of paresis at baseline was the only prognostic determinant for an increase in NHP physical mobility problems after 6 years.

CONCLUSIONS

Subjects with and without PPS did not differ with regard to changes in health status in a 6-year period. The fact that the extent of paresis was a prognostic factor for a decline in physical functioning is in accord with a (slow) decline in muscle mass, as a late effect of polio, that may lead to a decline in physical functioning as the reduced muscle capacity becomes less able to meet the demands of daily physical activities.

Post-polio syndrome and total health status in a prospective hospital study

New loss of function among patients with previous polio is frequently reported and has several causes. All patients referred to the Department of Neurology, Haukeland University Hospital, Bergen, for 13 months during 2000-2001 with diagnosis late effects of polio were examined prospectively to identify their symptoms and loss of function. Eighty-five patients aged 47-91 years with mean of 61 years were included. The most common complaints were pain (44%), muscular weakness (27%), and fatigue (16%). Muscular weakness occurred in lower limbs in 75%, in respiratory muscles in only 5%. Walking in stairs was impaired in 72% and outdoor walking in 65%. Seventeen patients (19%) reported no loss of function. Post-polio syndrome was diagnosed in 26% of the patients. Polio-related loss of function including cervical and lumbosacral radiculopathies, mononeuropathies and degenerative joint disease were found in an additional 53%. Eleven patients (13%) had distinct non-polio-related disorders that caused new loss of function. The remaining 8% had a stable condition. In conclusion, the majority of polio patients who seek hospital, experience a new loss of function because of polio-related disorders. A careful neurological examination is necessary to identify the correct diagnosis and treatment.

Perceived health in a population based sample of victims of the 1956 polio epidemic in the Netherlands

OBJECTIVE

To investigate perceived health and its relation to residual paresis from polio, late onset neuromuscular symptoms following poliomyelitis (LSP), and sex, in a population based sample of polio survivors.

METHODS

350 subjects traced from the notification records of the Dutch 1956 polio epidemic received a mailed questionnaire on residual polio paresis and new neuromuscular symptoms. Perceived health was measured using the Nottingham health profile. Respondents with new muscle weakness and new neuromuscular symptoms were considered as cases with LSP.

RESULTS

Health problems were perceived by 151 of the 260 respondents. Respondents with residual paresis had significantly more health problems than clinically recovered respondents for the Nottingham health profile category of physical mobility. The perceived health of respondents with LSP (45.5%) was significantly worse than that of respondents without LSP for all the health profile categories. Among the respondents with LSP, health status did not differ between those with residual paresis and those who had recovered, except for physical mobility. Female respondents with LSP reported worse health status than male respondents with regard to physical mobility and social isolation.

CONCLUSIONS

In this population based sample, health problems were frequently reported. They were mainly related to late onset neuromuscular symptoms following poliomyelitis, which were perceived by a substantial proportion of all polio survivors-not only subjects with polio residuals but also individuals who (subjectively) had recovered from polio.

Physical disability and the experience of chronic pain

OBJECTIVES

To obtain an insider's view about disability-related pain to help rehabilitation clinicians understand the experience and to show how people with disability manage daily living and encounters with other people.

DESIGN

Qualitative methods by using open-ended interviews and thematic analysis.

SETTING

Rehabilitation research program.

PARTICIPANTS

Nine adults with chronic physical disability and pain were recruited from study groups. The 9 included people with spinal cord injury, acquired amputation, or cerebral palsy.

INTERVENTION

Interview protocol.

MAIN OUTCOME MEASURE

Phenomenologic analysis of interviews based on codewords derived from interview topics and themes.

RESULTS

Study participants described pain as a part of daily living that influenced many lifestyle decisions. They characterized pain as plural, meaning that it has multiple locations, distinctive descriptions, and different implications. They also were concerned about pain being a mystery, having unclear causes and consequences. Typically they described pain as a personal venture, with little or dissatisfying communication about pain with family, friends, or health care providers.

CONCLUSIONS

Understanding pain associated with physical disability can help guide rehabilitation practitioners in their pain assessments, interventions, and related research. Our findings suggest that some people with disability-related pain may benefit from reassurance and specific planning for expected and unexpected pain episodes.

Submaximal exercise capacity and maximal power output in polio subjects

OBJECTIVES

To compare the submaximal exercise capacity of polio subjects with postpoliomyelitis syndrome (PPS) and without (non-PPS) with that of healthy control subjects, to investigate the relationship of this capacity with maximal short-term power and quadriceps strength, and to evaluate movement economy.

DESIGN

Cross-sectional survey.

SETTING

University hospital.

PARTICIPANTS

Forty-three polio subjects (25 PPS, 18 non-PPS) and 12 control subjects.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Power output, oxygen uptake, and heart rate were measured in an incremental submaximal cycle ergometry test. Maximal short-term power was measured in 5-second all-out efforts. Knee extensor strength was measured on a chair dynamometer.

RESULTS

The mean submaximal power +/- standard deviation at 80% of heart rate reserve of 83.8 +/- 29.9 watts in the polio subjects was significantly less than the mean submaximal power of 142.1 +/- 30.4 watts in the control group. However, expressed as a percentage of the maximal short-term power, submaximal power did not differ between the groups. Strength and maximal short-term power correlated significantly (p < .005) with submaximal power (r = .64 and .76, respectively). The oxygen uptake was higher than theoretically expected for the given submaximal power output in polio subjects, and appeared to increase with increasing asymmetry in strength and power between legs. No differences were found between PPS and non-PPS subjects.

CONCLUSION

The submaximal work capacity of polio subjects was severely reduced, mainly in association with the reduced muscle capacity. And, because of a reduced movement economy, their energy cost was elevated. Although muscle loads in activities such as walking and climbing stairs differ from cycling, they also may require elevated relative levels of effort, predisposing subjects to premature fatigue in sustained activity.

Special considerations for treating dental patients exhibiting the "post-polio syndrome"

A condition called "Post-polio Syndrome" (PPS) is a special type of neuromuscular disturbance that affects some elderly patients who had polio myelitis either as children or as young adults. It has been reported that approximately 1,600,000 polio survivors are alive today. Most will seek dental care, and up to half of the survivors will present with some form of PPS. This paper describes polio, its characteristics, and the long-term consideration of PPS, and discusses the special clinical implications related to this condition. Special emphasis is placed on physical impairments, breathing problems, and difficulty swallowing. Also included are sections discussing such topics as patient scheduling, office design and housekeeping, patient management, oral hygiene, diagnostic procedures, drug and pain management, and general health considerations.

Muscular effects in late polio

New or increased muscular weakness, fatigue and muscle and joint pain with neuropathic electromyography (EMG) changes in a person with a confirmed history of polio constitute the cardinal symptoms of the post-polio syndrome. Unusual tiredness or fatigue is a common complaint in late polio subjects as is intolerance to cold. Fatigue in polio subjects can have several explanations: emotional fatigue, central nervous system fatigue, 'general' fatigue and/or neuromuscular fatigue. Some studies indicate central fatigue, but it is unclear how often and to which degree there will be a central muscular fatigue. Polio patients are known to be deconditioned (reduced function because of low activity level), and aerobic power is reduced. Defects in the neuromuscular transmission may be present but are not seen in all post-polio subjects with reduction in force and increased fatigability. The fatigue experienced by late polio patients is most likely an augmented peripheral muscle fatigue. Possible explanations may be an imperfection in the sarcoplasmatic reticulum with altered calcium release mechanisms (activation) or in sliding filament function (contractile properties). This may be a secondary effect to the enlarged muscle fibres. However, the prolonged subjective feeling of fatigue reported despite unchanged maximal voluntary contraction (MVC) remains unexplained.

Health-related quality of life outcomes measures

OBJECTIVE

To review critically the features of measures of generic health-related quality of life (HRQOL) for disability outcomes research.

DATA SOURCES

A search of electronic databases, summary reviews, books, and government documents was performed. Comment and experiences from participants of a conference on outcomes research were also incorporated.

STUDY SELECTION

English language literature from scientists from a broad range of disciplines and research settings, including medicine, nursing, social science, and public health, and health services research and practice.

DATA EXTRACTION

A critical review of measures that have been or might be used to measure disability outcomes.

DATA SYNTHESIS

Commonly used generic measures of HRQOL can be applied to disability outcomes research with some caveats. Three common tools are the Medical Outcomes Study Short-Form Health Survey (SF-36), Sickness Impact Profile (SIP), and Quality of Well-Being (QWB) scale. The SF-36 and SIP have been used with some success in research with people with disability. The QWB scale has been used less frequently.

CONCLUSION

Most studies using generic HRQOL tools are of groups with specific impairments rather than heterogeneous groups of people with disability. None of the tools appears to measure HRQOL without some potential biases (eg, inappropriate wording) for people with disability, but more specific testing of these problems is needed. Also needed are studies to determine whether these tools can measure meaningful longitudinal changes.

The health-related quality of life of patients suffering from the late effects of polio (post-polio)

In Sweden alone, there are today approximately 10 000-16 500 polio survivors. Between 60% and 80% experience new symptoms several years after the initial attack of poliomyelitis. The aims of this study were to investigate and describe the self-rated health-related quality of life and functional status of a group of Swedish patients with post-polio, to investigate whether any differences within the group could be related to demographic or disease-specific data and to compare the post-polio patients with individuals sampled from the general population. Data were obtained by using two questionnaires, the Swedish Health-Related Quality of Life Questionnaire (SWED-QUAL) and the Sickness Impact Profile (SIP). A total of 150 patients, 86 women and 64 men with median age 61 (20-82) years, were consecutively included. The study showed that the patients mainly reported that their physical, functional status was affected by their post-polio condition. Factors found to be associated with the physical, functional status were age and the number of parts of the body affected by the polio. On comparing the post-polio patients with two samples from the Swedish general population, it was found that the patients reported a poorer functional status and health-related quality of life. The women with post-polio reported more pain, as compared with both the men with post-polio and the women in the general population sample. The family life of the patients - in contrast to their physical abilities - did not seem to be affected by the new deteriorating condition. It is concluded that, owing to the wide range of symptoms, the patients with post-polio need care and support from multidisciplinary teams, including nurses and occupational therapists.

Strength assessment in postpolio syndrome: validity of a hand-held dynamometer in detecting change

OBJECTIVES

To investigate the validity, the intraexaminer and interexaminer reproducibility, and the ability to detect change of a hand-held dynamometer (HHD) in strength measurements in former polio subjects.

DESIGN

HHD measurement of knee extensor strength was compared with the criterion standard of a chair dynamometer measurement in 49 subjects. The "break" method was used for HHD measurements. Reproducibility was studied for six lower extremity muscle groups in 28 subjects. The measurements were performed by one experienced and one inexperienced examiner on two separate occasions, with an interval of 1 week. The examiners were blinded to each other's and to previous results.

SETTING

University hospital.

SUBJECTS

Volunteer sample of former polio subjects.

RESULTS

For knee extension, the forces that could be measured with the HHD were limited to approximately 200N. Although the intraclass correlation coefficients were high (.75 to .98), the 95% limits of agreement between measurements showed large intervals for differences between two measurements (ratio intervals ranging from .76-1.52 to .52-2.77). The intraexaminer reproducibility for the experienced examiner was superior to that of the inexperienced examiner. The reproducibility of the inexperienced examiner showed systematic bias, with significantly higher strength values for the second session measurement of three muscle groups.

CONCLUSION

The device has good validity in the lower force range. However, because the agreement between measurements was poor, it has limited ability to detect a change in muscle strength. Therefore, this method is unable to detect small changes in lower extremity muscle strength in former polio patients.