Post-Polio Impairments And Physical Activity

In the past few years, many polio survivors have experienced late-onset neuromuscular symptoms like fatigue, pain, new and unusual muscular deficits, on healthy muscles as well as deficient muscles initially affected by the Poliovirus along with decreased functional abilities. These symptoms have been termed Post-Polio Syndrome(PPS). 1Associated symptoms are weight gain, sleep apnea, walking difficulties, swallowing problems, breathing problems and sensitivity to cold.

According to the World Health Organization (WHO), PA of 150 minutes per week or as moderate to vigorous PA a minimum of 30 min per day most days of the week is the recommended guideline. It has been shown that only 38% of adults with a disability meet the international recommendations for PA compared to 49% in those without disability. 4 Also, levels of PA decline with increasing age. Impairments in PPS such as muscle weakness, muscle fatigue, general fatigue, cold intolerance, and musculoskeletal pain both at rest and during PA can lead to activity limitations, such as reduced walking ability, both indoors and outdoors. This, in turn, can restrict activities of daily living and may lead to a more sedentary lifestyle.

PPS is not an infectious process unlike the original poliomyelitis, and persons experiencing PPS do not shed poliovirus. Yet, while an enormous amount of time and resources have been devoted to preventing polio, scant attention has been paid to the estimated 12 to 20 million individuals living with polio sequelae worldwide. India has surpassed more than 3 successful years of eradication declared a polio-free country, although it has a large number of polio survivors, almost around 80 lakh [8 million] people. According to a previous study, prevalence of PPS among polio survivors was found to be almost 86% in Gujarat which is similar to studies of other countries.

Many persons with late effects of polio may have difficulties or are unable to achieve desired levels of physical activity because of their impairments and activity limitations associated with their disability. The impairments following late effects of polio, together with walking limitations, fear of falling, and risk of falls, potentially also affect the possibility to be physically active. PA is a central component in not only preserving health but also maintaining and improving quality of life. Physical inactivity in disabled population is more common than in general population and hence improving PA behavior in people with disabilities is even more important in order to prevent the hazards of physical inactivity. Knowledge of the amount and type of PA in persons with late effects of polio is very scarce and assessing PA in this population can lead to a better understanding of their lifestyle and enable in creating management strategies for the same. This study intends to determine their physical activity and self-reported impairments and their correlation in persons with PPS.

Materials and Methods

A cross sectional study was conducted over a period of 2 years among community dwelling persons with PPS selected from various clubs, non-government organizations, associations and also from hospitals and their databases in Gujarat, India. Study was approved by Institutional Ethics Committee (IEC-CMPP/01/2017-18). The study was registered in the Clinical Trial Registry of India (CTRI/2017/11/010634).

The study was conducted on a convenience sample of 80 participants, both men and women with PPS according to Halstead criteria (1985). There should be no other medical explanation found and there should be a gradual or abrupt onset of new neurogenic weakness. Those between 18 to 65 years, having locomotor ability with or without assistive device were included, and individuals who were unable to cooperate due to cognitive impairment, had disabling co-morbidity that influenced the outcome variables, or if they were using any psychotropic drugs were excluded. Nature and purpose of study was explained to them in the language they could understand, and informed written consent was obtained.

A complete neuromuscular examination was done and participants were interviewed and assessed by the principal investigator. They were then assessed for the outcome measures, in a personal interview which lasted for about 30 minutes. Details like age, gender, occupation, Body Mass Index (BMI), working experience, age of onset of acute polio, use of assistive devices, number of body sites affected with residual paresis were also documented. Outcome measures consisted of Physical activity and disability survey (PADS) and Self-Reported Impairments in Persons with Late Effects of Polio (SIPP).

PADS which is a 31-item self-report questionnaire that provides a measure of the day-to-day level of PA in people with disabilities. It consists of four subscales focusing on exercise, leisure, household activities, work/school, and a part describing whether they received therapy or used a wheelchair. Data were then converted into minutes per day for each subscale and used to calculate the sum score of PADS. The original PADS has shown good psychometric properties, and has been used in persons with multiple sclerosis, arthritis, stroke and late effects of polio. For an accurate measurement, local linguistic versions of PADS in Gujarati language, translated as per the guidelines of WHO, was used.

The internal consistency of the PADS-Gujarati as examined by Cronbach’s alpha (𝛼) was 0. 84. SIPP is a 13-item scale where participants rate how much they have been bothered during the past two weeks by various impairments, directly (e. g. muscle weakness, pain, fatigue) or indirectly (e. g. sensory disturbances, mood swings) related to late effects of polio. There are four response options, ranging from 1 (not at all) to 4 (extremely). The sum score is calculated by adding the score for each item and ranges from 13 to 52 points. A higher score indicates that the participant is more bothered by the impairments related to late effects of polio. In this study, this outcome was assessed by the principal investigator and then subjects were explained and asked to rate it across the options.

IBM SPSS version 20. 0 was used for analysis and significance level was assigned at 5%. Descriptive statistics were obtained for age, gender, BMI and other measures taken in self-structured survey questionnaire. Normal distribution was checked using histograms and KS test, and appropriate test of correlation analysis was then applied. Outcomes were found to be normally distributed and hence correlation was computed using Pearson’s test of correlation.

In the present study, subjects were found to be physically active for 70 minutes per dayas measured using PADS, and had a mean score of 19. 59 + 2. 43 (95% CI: 13. 00-30. 00) in severity of impairments. According to the WHO guidelines, at least 150 minutes per week is recommended inclusive of household chores but they have to be at least moderate in intensity and performed in bouts of at least ten minutes in order to be beneficial for health. 4 In this study also, participants were physically active for 70 minutes/day, and were more active in household activity with mean score of 24 minutes/day. Although they were physically active, most of this was performed in household and leisure domains, and not as structured exercises. In a similar study by Winberg C et al on PA in PPS, participants met the WHO recommendations 43% of the participants were active more than 30 min per day, but in the exercise and leisure activities combined which is in contrast to the current study where PA was more in household and leisure.

Another significant finding in the current study was that, in spite of being active, participants did have severe impairments which significantly and negatively correlated with PA(r=-0. 531, p.) Consistent with previous study by Garip Y et al, self-reported impairments in this study were high, who found that the most common symptoms in PPS were fatigue (76. 2%) and muscle pain (71. 4%). In accordance with this, the present study also had muscle/joint pain during physical activity prevalent among 93% of subjects, followed by general fatigue among 89%, and muscle weakness and muscle fatigue among 76% subjects each.

Also, in a study by Nollet on disability and functional status in Dutch patients with PPS, 78% of the patients selected fatigue as their major problem. Conde MT et al also concluded that in PPS, the most frequent complaints were fatigue (87. 1%), muscle pain (82. 4%), and joint pain(72%). Another finding in the current study was that impairments also significantly though weakly correlated with age (r=0. 387, p=0. 01). Hence, it can be said that people with PPS are experiencing overall decline in their health status with advancing age.

None of the subscales of PADS correlated with SIPP, suggesting that each domain of PA individually does not necessarily relate to impairments, but in totality does account for a significant correlation. Multilinear regression analysis of PA with SIPP, followed by SIPP when added with age showed a weak yet significant variance. This again, is in this contrast to the findings of Winberg C et al, who concluded that increasing age may not necessarily result in lower levels of PA, rather people may spend more time after retirement in PA.

Although PADS used for assessing physical activity is a valid and reliable tool to assess PA in disabled people, using a pedometer or accelerometer is considered a gold standard measure. Wheelchair bound subjects were not analyzed and hence the findings cannot be generalized to an entire population of persons with PPS. And future studies with a varied PPS population can be undertaken.

In conclusion, PA levels in PPS are high, and mainly in the form of household and leisure activities contributing to fairly reasonable physical activity across the day. However, they do not consist of structured exercises which are better suited to them based on their physical impairments and nature of condition. PA also moderately correlates with impairments, highlighting the need of appropriate intervention strategies to alleviate the health status.