Post-polio Syndrome
Andre Vieira
University of Massachusetts, Boston
According to the World Health Organization (WHO), Polio or Poliomyelitis, is a highly infectious disease that mainly affects young children. Symptoms of this disease include fever, fatigue, headaches, vomiting, stiffness in the neck, and pain in the limbs (WHO). Today, there is no cure for Polio, it can only be prevented by vaccination.
According to the National Institute of Neurological Disorders and Stroke (NIH), years after someone survives polio, they might develop what is called as Post-Polio Syndrome (PPS). When this happens, people start to experience weakening of muscles that had previously been affected at the time of the initial polio infection (NHI). Symptoms associated with this syndrome can include fatigue, muscle atrophy, joint pain, and some skeletal deformities. The severity of these symptoms can vary greatly between each person with some experiencing very mild symptoms while others will experience severe symptoms. These symptoms can have a great impact on the ability of someone with post-polio to perform normal daily living activities and function independently (NHI). The incidence of PPS is unknown however, it is estimated that 25-40% of polio survivors go on to develop PPS (NHI).
According to the NHI, there is presently no test to identify post-polio, therefore diagnosis is greatly dependent on clinical diagnosis. As an example, the case study, Risk Factors for Post-Polio Syndrome Among an Italian Population: a Case Control Study, by Bertolasi et al (2012), defines their criteria to diagnose post-polio syndrome according to the European Federation of Neurological Societies (EFNS). The EFNS diagnosis criteria is based on confirmed history of polio, a period of partial or fairly complete functional recovery after the acute episode, a period of at least 15 years of stable neurological function and two or more new symptoms. These symptoms include new muscle weakness, muscle fatigue, muscle atrophy, joint pain, breathing or swallowing problems, sleep disorders, and exclusion of other neurological, medical and orthopedic problems (Bertolasi et al, page 1272). The goal of the study was to detect possible risk factors that could potentiate the development of PPS. The authors found that being a female and the severity of respiratory impairment at acute infection seem to be risk factors for PPS (page 1274). This study also concludes that the severity of the “respiratory disturbance during the acute infection” (page 1274), and the use of orthoses and aids during recovery, are correlated with higher risk of PPS development. According to this study, the severity of motor neuron damage is positively related with developing PPS later in life.
According to the NIH, there are no pharmaceutical treatments that will stop muscle deterioration caused by PPS today. There are however, some studies that have shown that light exercise might improve muscle strength and functional capacity. One of those studies, Short-term effects of aerobic exercise on functional capacity, fatigue, and quality of life in patients with post-polio syndrome, by Oncu et al (2009), investigated the impact of hospital and home exercise programs in improving aerobic capacity, fatigue and quality of life. This study showed that both group of patients, hospital and home, showed improvements in fatigue and quality of life. In addition, the hospital exercise group also showed improvements in functional capacity (page 160). According to Oncu et al, “muscle weakness, pain and fatigue often cited by patients during daily activities might be related to reduced pVO2” (page 160), potentially negatively impacting the way patients go about their lives as well as a