Men With Late Effects of Polio Decline More Than Women in Lower Limb Muscle Strength: A 4-Year Longitudinal Study

Risk factors for functional deterioration in a cohort with late effects of poliomyelitis: A ten-year follow-up study

BACKGROUND

More than 7000 patients developed poliomyelitis during the main epidemic in the fifties in Israel. In recent years, there is a further deterioration in their condition due to accelerated aging process and post-polio syndrome.

OBJECTIVE

To evaluate the risk factors for the progression of functional status in a cohort of patients with late effect of poliomyelitis over a period of ten years.

METHODS

A cross-sectional cohort study including 82 individuals with late effect of poliomyelitis evaluated over ten years. Mean age was 67±8.5 years, 52.4%were men and 79.3%were Jewish. Functional status was evaluated by activities of daily living (ADL) questionnaire. Risk factors, including general comorbidities, history of poliomyelitis infection, use of assistive devices, employment, and physical activity statuses were evaluated using specific questionnaires.

RESULTS

Independence in ADL functions deteriorated significantly over ten years. Older age, ethnicity, use of a wheelchair, and use of orthotic devices in childhood were risk factors for deterioration in ADL function. No correlation was found between the presence of other comorbidities or poliomyelitis parameters and worsening of ADL functions.

CONCLUSIONS

Late effect of poliomyelitis was associated with deterioration in ADL functions probably due to the combined effect of the initial severity of the paralytic poliomyelitis symptoms and accelerated aging.

Psychometric Properties of the Walking Impact Scale (Walk-12) in Persons with Late Effects of Polio

BACKGROUND

Many persons with late effects of polio (LEoP) perceive walking limitations in everyday life. A common rating scale to assess walking limitations is the Walking Impact Scale (Walk-12). However, there is limited knowledge about its psychometric properties.

OBJECTIVE

To investigate the psychometric properties of Walk-12 in persons with LEoP.

DESIGN

Rasch model analysis of cross-sectional data.

SETTING

University hospital.

PARTICIPANTS

A total of 325 persons with LEoP (175 women; mean age 70 ± 10 years).

MAIN OUTCOME MEASUREMENT

The Walk-12, comprising 12 items with five response categories ranging from 1 (not at all) to 5 (extremely).

METHODS

Data of Walk-12 were collected by a postal survey. The Rasch model analysis was used to analyze unidimensionality of the scale, local dependency, targeting, hierarchical order of items, Differential Item Functioning (DIF), response category functioning, and reliability (Person Separation Index, PSI). Raw score transformation to interval measurements was also performed.

RESULTS

The analysis revealed that Walk-12 was multidimensional and suffered from some local dependency. Targeting was compromised among persons with less and more walking limitations. Hierarchically, the most difficult item to perform was "running" and the easiest was "walking indoors with support". There was a minor DIF for gender in one item ("support when walking outdoors"). Reliability was high (PSI = 0.94). Disordered response category thresholds were found for three items; when merging the middle response categories for these items model fit slightly improved and unidimensionality was achieved.

CONCLUSIONS

The Walk-12, in its current version, does not fully meet the rigorous psychometric Rasch measurement standards in persons with LEoP. Further development of the scale is warranted, including merging response categories and complementing Walk-12 with objective measures of gait in order to improve targeting. As these limitations can be considered minor, the current version of Walk-12 can still be useful for research and clinical practice.

A very long-term longitudinal follow-up of persons with late effects of polio

BACKGROUND

As many as 60-80% of persons with a history of polio myelitis develop new symptoms, such as new or increased muscle weakness, muscle and joint pain, and fatigue several decades later, called postpolio syndrome (PPS). This may affect their ability to perform activities of daily living (ADL). It is still unclear if the patient's symptom is getting worse and in that case how much/fast the decline is.

AIM

The aim of the present study was to evaluate long-term changes in disability in community dwelling patients with prior poliomyelitis, in contact with a polio clinic 14-16 years post their first assessment.

DESIGN

A cross sectional longitudinal study.

SETTING

Polio clinic.

POPULATION

Fifty-two persons recruited from an earlier 4-year follow-up participated in the study.

METHODS

A questionnaire was mailed prior to the visit at the polio clinic. Physical testing was performed by measuring muscle strength, walking speed and handgrip force.

RESULTS

Overall there was a small change in muscle strength. A significant reduction in the right leg was found for flexion 60° and in dorsal flexion. For the left leg a significant reduction was found for plantar flexion. In the walking tests, a significant reduction was seen for spontaneous walking speed. No significant interaction between decrease in spontaneous walking speed and the variables age, BMI and flexion 60° and dorsal flexion in the right leg was seen.

CONCLUSIONS

This cross-sectional longitudinal study shows small changes in muscle strength and disability. The results may imply that symptoms associated with late effects of polio are not progressing as fast as we had previously thought.

CLINICAL REHABILITATION IMPACT

When health care professionals meet persons with late effects of polio the knowledge of long-term consequences of deterioration is important. Knowing that the deterioration is not as fast as previously thought, can help us to support the person in having a healthy lifestyle, stay active and encourage to perform adapted physical training.

Post-polio Syndrome: More Than Just a Lower Motor Neuron Disease

Post-polio syndrome (PPS) is a neurological condition that affects polio survivors decades after their initial infection. Despite its high prevalence, the etiology of PPS remains elusive, mechanisms of progression are poorly understood, and the condition is notoriously under-researched. While motor dysfunction is a hallmark feature of the condition, generalized fatigue, sleep disturbance, decreased endurance, neuropsychological deficits, sensory symptoms, and chronic pain are also often reported and have considerable quality of life implications in PPS. The non-motor aspects of PPS are particularly challenging to evaluate, quantify, and treat. Generalized fatigue is one of the most distressing symptoms of PPS and is likely to be multifactorial due to weight-gain, respiratory compromise, poor sleep, and polypharmacy. No validated diagnostic, monitoring, or prognostic markers have been developed in PPS to date and the mainstay of therapy centers on symptomatic relief and individualized rehabilitation strategies such as energy conservation and muscle strengthening exercise regimes. Despite a number of large clinical trials in PPS, no effective disease-modifying pharmacological treatments are currently available.

Adults with polio are at risk of hip fracture from middle age: A nationwide population-based cohort study

BACKGROUND

Having motor impairment since childhood and being at risk of osteoporosis and falls, adults with polio would be more likely to suffer a hip fracture (HF) and may experience different epidemiological characteristics from the general population.

OBJECTIVE

To estimate the risk and incidence of HF in adults with polio.

DESIGN

Using a national database, we conducted a population-based cohort study. We identified patients with polio using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) code of 138. For each patient with polio, we randomly selected five age- and sex-matched control subjects. Those subjects aged <40 years were excluded. We analyzed participants aged 40˜64 years (middle-aged) and subjects aged ≥65 years (elderly) separately and recognized subjects who had an HF (ICD-9-CM code, 820) only when they received hospitalization to care for the illness from January 1, 2003 to December 31, 2008.

RESULTS

We identified 403 adults with polio (mean age ± standard deviation, 47.2 ± 8.6 years). Compared to the controls, patients with polio had a higher incidence of HF (all, 4.1 vs. 1.1/1000 person-years, p = 0.002; middle-aged, 2.3 vs. 0.3/1000 person-years, p < 0.001; male, 6.2 vs. 0.9/1000 person-years, p < 0.001); had a younger mean age (±standard deviation) of fracturing a hip (61.0±14.9 vs. 74.4±9.3 years, p = 0.015); had a lower cumulative HF-free probability (±standard error) before the age of 65 years (0.970±0.017 vs. 0.988±0.007, p<0.001) and throughout the study duration (0.415 ± 0.296 vs. 0.682 ± 0.158, p<0.001); and had a higher risk of HF, yielding an adjusted hazard ratio (95% confidence interval) of 3.58 (1.45˜8.79, p = 0.006). Patients with polio aged >48.2 years were likely to experience an HF.

CONCLUSIONS

Adults with polio are at risk of HF. A customized HF prevention program is important for people with polio. The program should be started early in middle-age and should include men.

Post-polio syndrome and the late effects of poliomyelitis: Part 2. treatment, management, and prognosis

Post-polio syndrome (PPS) is characterized by new muscle weakness and/or muscle fatigability that occurs many years after the initial poliomyelitis illness. An individualized approach to rehabilitation management is critical. Interventions may include rehabilitation management strategies, adaptive equipment, orthotic equipment, gait/mobility aids, and a variety of therapeutic exercises. The progression of muscle weakness in PPS is typically slow and gradual; however, there is also variability in both the natural history of weakness and functional prognosis. Further research is required to determine the effectiveness of selected medical treatment. Muscle Nerve 58:760-769, 2018.

Predictors of changes in gait performance over four years in persons with late effects of polio

BACKGROUND

Reduced gait performance is common in persons with late effects of polio.

OBJECTIVE

To identify predictors of change in gait performance over four years in persons with late effects of polio.

METHODS

Gait performance was assessed annually in 51 ambulatory persons (mean age 64 years, SD 6) by the Timed "Up & Go" (TUG), Comfortable and Fast Gait Speed (CGS, FGS), and 6-Minute Walk Test (6MWT). Isokinetic knee extensor and flexor muscle strength was measured with a Biodex dynamometer. Mixed Linear Models were used to analyze changes in gait performance and to identify any predictors of change among the covariates gender, age, body mass index, time with new symptoms, baseline reduction in gait performance and knee muscle strength.

RESULTS

There were significant linear effects over time (reduction per year) for three gait performance tests; CGS (0.8%; p < 0.05), FGS (1.7%; p < 0.001), and 6MWT (0.7%; p < 0.05) with significant random effects for all tests. The strongest predictor of a change in gait performance was the individual variations in the knee flexor strength (p < 0.001).

CONCLUSION

The small gradual reduction in gait performance over time in persons with late effects of polio is primarily determined by the individual variations in the knee flexor strength.