High Prevalence of Cardiovascular Comorbidity and Chronic Pain in Polio Survivors as Compared to the General Population

Special Article – Disability and Rehabilitation

Phys Med Rehabil Int. 2018; 5(1): 1138.

High Prevalence of Cardiovascular Comorbidity and Chronic Pain in Polio Survivors as Compared to the General Population

Schwartz I1, Gartsman I1, Adler B2, Friedlander Y2, Manor O2, Levine H2 and Meiner Z1*

1Department of Physical Medicine and Rehabilitation, Hadassah Medical Center, Israel

2The Hebrew University-Hadassah, Braun School of Public Health, Israel

*Corresponding author: Zeev Meiner, Department of Physical Medicine and Rehabilitation, POB 24035, Hadassah University Hospital, Jerusalem, 91240, Israel

Received: January 20, 2018; Accepted: February 21, 2018; Published: February 28, 2018


Objective: The aims of this study are to investigate how the interaction between polio sequelae and aging contributes to the general health and functional level of polio survivors and to identify factors which contribute to the increased morbidity of polio survivors when compared to the general population.

Design: A case-control study.

Setting: Post-polio clinic in a tertiary university center.

Participants: 195 polio patients who attended post-polio clinic.

Interventions: Not applicable.

Main Outcome Measure(s): Demographic, medical, social, and functional data was evaluated using a generalized questionnaire which was administered in a national health surveys with adaption to the polio population. This data was compared, using logistic regression analysis, to 768 age and sex matched controls from the general population.

Results: The analysis indicated that the rate of cardiovascular diseases (p‹0.0001), hypertension (p=0.006), diabetes (p‹0.0001) and chronic pain (p‹0.0001) was significantly higher among polio patients. Male gender, hypertension and single status increased the rate of cardiovascular diseases among polio survivors. However, unlike the general population, the functional status of polio survivors was not affected by cardiovascular diseases or chronic pain.

Conclusions: Our study demonstrated that long-standing poliomyelitis has a deleterious impact on the general health and functional level of polio survivors emphasizing the need for early screening for vascular risk factors and special health promotion program to prevent their further decline.

Keywords: Poliomyelitis; Cardiovascular comorbidity; Chronic pain; Functional outcomes; Post-polio syndrome


According to the World Health Organization it is estimated that 12–20 million people are living with sequelae of poliomyelitis worldwide [1]. Long-standing poliomyelitis has a deleterious effect on the general medical health and functional status of polio survivors as compared to the general population [2,3].

During the 1950’s in Israel, more than 7000 people were afflicted with paralytic poliomyelitis including a significant prevalence of childhood cases [4-6]. As a result of the illness, throughout their life span these patients suffered from various motor and functional disabilities. In a recent Israeli census conducted following the 2007 legislation of the Polio Victims Compensation Law [7], over 2500 polio survivors were identified.

Several studies have shown that paralytic polio patients are more prone than the general population to developing cardiovascular diseases (CVDs), hypertension, lung diseases, diabetes and orthopedic complications such as osteoporosis, fractures and scoliosis [8-10]. The reasons behind the increased health risks of polio survivors are unclear, though the predominant explanation is their impaired mobility and consequent sedentary lifestyle. However, these studies compared the prevalence of comorbidities alone and not factors influencing these comorbidities, such as socio-demographic information, medical risk factors and levels of disability.

The primary goals of this study were twofold; to investigate whether such disparities in the prevalence of cardiovascular comorbidities and chronic pain between polio survivors and the general population exist in Israeli polio population and if so, to identify the main factors contributing to these discrepancies.

An additional purpose of the study was to assess whether a history of polio infection and its severity are risk factors for cardiovascular disease or chronic pain. The findings of this study may be important in identifying the risk factors for medical and functional deterioration in polio survivors and to developing programs aimed at their prevention.



This case-control study included 195 polio patients attending the post-polio clinic in PM&R department of the Hadassah Mount Scopus Medical Center in Jerusalem. The study was approved by the ethics committee of Hadassah Medical center. The post-polio clinic in Hadassah Mount Scopus Medical Center was founded in 1997 and serves as a regional center for the polio population in Jerusalem and the surrounding areas, a region home to 800,000 inhabitants. Each patient is evaluated once every 6 months by a senior physiatrist with specialized expertise in polio and the post-polio syndrome. The evaluation entails a medical, neurological and functional examination. Following the evaluation, a physiatrist makes recommendations such as physical rehabilitation, specialized equipment and adaptations in home or work environments. All 209 patients of the post-polio clinic between 2010 until 2012 were asked to participate in this study; 195 patients accepted and 14 either refused or were unavailable. Each participant was interviewed by a rehabilitation physician experienced in the care of polio patients. The one hour interview usually took place in the PPS clinic in the hospital (92%), in some cases in the patient’s home (5%) while 3% of the patients were interviewed by phone.

The control group was a random stratified sample from the international health survey which was conducted by the Israel Central Bureau of Statistic in 2003/2004 [11]. The health survey samples were divided into 28 strata by sex, (male-female) religion (Jews-non Jews) and age (45-49,50-54,55-59,60-64,65-69,70-74,75+), while from each stratum a random sample of controls was selected. The number controls selected was 4 times the number of polio cases in each stratum, with one exception; there were insufficient numbers of male non-Jews aged 45-49 and therefore for this stratum all available controls were selected. The control group sample included 768 controls with distribution of age, sex and religion comparable to the polio group.

Survey questionnaire

The demographic, medical, social, and functional data of the polio patients was evaluated through the use of a questionnaire designed to correlate with the relevant sections of the National Health Surveys conducted by the Israel Central Bureau of Statistic in 2003/2004 [11]. The demographic data collected included current age, age of polio infection, gender, ethnic origin and place of birth. The socioeconomic data surveyed marital status, education and occupational status. Comorbidity data according to patient’s report and family doctor diagnosis (ischemic or other heart diseases, stroke, high blood pressure, diabetes mellitus, chronic back or neck pain) was obtained from a comorbidity questionnaire, while level of difficulties in performing activities of daily living (ADLs) was obtained via a self- report questionnaire.

Statistical methods

Descriptive statistics were calculated for the continuous variables (mean, standard deviation and range) and differences between the two populations evaluated by t-test. Percentages and rates were calculated for the categorical variables and differences were assessed by chi square test. Logistic analysis was used to determine how well vascular risk factors and demographics predicted cardiovascular diseases and chronic pain Differences in the logistic function between polio survivors and general population were evaluated by adding interaction to the logistic regression. P‹0.05 was considered as significant.


Demographic data of polio survivors in Jerusalem as compared to age and gender matched general population in Israel

The summary of the demographic data from the 195 (out of 269) polio patients who agreed to participate in the study, is presented in Table 1. The mean age of the polio survivors was 57.6±10.5 (33-84); 52.6% men and 47.4% women. The group included 145 (74.9%) Jews and 48 (25.1%) Arabs, most of whom were Muslims. The percentage of those married was similar in both populations. Only 84.7% of the polio survivors had children as compared to 95.3% in the general population (P‹0.0001), whereas the total number of children per family was not different between the two groups. Polio survivors were better educated than the general population with slightly higher mean years of education (p= 0.058). According to our results, 37.1 % of polio survivors were still employed as compared to 52.4 % in the general population (p=0.007), with more than 90% of those employed reporting some disability at their work place. Nearly 50% of our polio population acquired the disease around their first birthday, almost 20% had involvement of 3 or more limbs, 50% suffered from scoliosis and 26% had respiratory disturbances. Almost 70% of the polio survivors required some orthoses for mobilization (data not shown). Regarding functional status, polio survivors were significantly less independent in their ambulatory capacity in and out of doors and in their ADL functions (Table 2).