Navigation Links
Survivors of childhood polio do well decades later as they age

Mayo Clinic researchers have found that years after experiencing childhood polio, most survivors do not experience declines greater than expected in their elderly counterparts, but rather experience only modest increased weakness which may be commensurate with normal aging.

"Other researchers have suggested that polio is a more aggressive condition later in life, but we've actually found it to be relatively benign," says Eric Sorenson, M.D., Mayo Clinic neurologist and lead study researcher. "Our results suggest that polio survivors may not age any differently than those in the normal population -- they're not doing too badly compared to their peers. This tells us that the cause for the decline in muscle strength in polio survivors may be aging alone."

Polio is a contagious, viral illness that peaked in the United States in 1952, when 3,000 people died of the disease. Mass immunizations in the mid-1950s began to slow the spread of the disease, and the last case of polio not caused by a vaccine occurred in the United States in 1979. The three major types of polio include spinal polio, a paralytic polio that attacks nerve cells in the spinal cord; bulbar polio, in which the virus attacks motor neurons in the brainstem; and bulbospinal polio, a combination of spinal and bulbar polios. The effects of polio run the gamut from a complete return to normal function to paralysis of limbs to acute death. Following the illness, most patients are worried about their long-term prognoses, according to Dr. Sorenson.

To conduct this study, the researchers randomly selected a group of 50 polio survivors from the general population of Olmsted County, home of Mayo Clinic, and followed them for 15 years. The average age of participants at the study's start was 53, and the patients were an average of 40 years past their childhood experience with polio. The researchers measured strength and loss of neurons at the beginning of this period, and then again five a nd 15 years later with electrophysiological testing, strength testing and timed tests of performing basic functions. They found modest declines. Each patient also completed questionnaires about symptoms of progressive weakness at the beginning and end of the study period. Though the majority complained of progressive weakness during the time they were studied, these symptoms did not correspond with their actual magnitudes of decline over time. Rather, the researchers found patients' symptoms experienced were associated with the degree of residual weakness immediately following their polio infections.

"Overall, we found that strength changed very little in these polio survivors as they grew older, and we discovered the neurons dropped off at a rate comparable to other non-polio survivors as they aged," says Dr. Sorenson. "We concluded this was normal aging on top of their old deficits. Very few had to change their homes or add adaptive equipment. Those who had weakness problems during our study had a larger deficit at the end of their childhood disease, making them more likely to develop symptoms. So, as deficits at the end of the disease increase, the probability of experiencing post-polio symptoms increases."

The discrepancy between what some of the patients experienced with growing weakness and their actual measurements of strength and neuronal loss likely is due to increased sensitivity due to their disease experiences, according to Dr. Sorenson.

"Patients feel their weakness progressing, but when you measure it, it's very modest," he says. "Likely, they lost so much strength at the time of their illness that any change is very noticeable to them. Though the likelihood is high that patients who have had childhood polio will complain of weakness later in life, they can expect years of stability without the need for major lifestyle modifications."

Source:Mayo Clinic

Related biology news :

1. Newly discovered virus linked to childhood lung disorders and Kawasaki disease
2. Emergence of cancer as major cause of childhood death in developing countries is not being adequately addressed
3. UCLA researchers identify key enzyme linked to childhood blindness
4. Large-scale genomics project will hunt genes behind common childhood diseases
5. Mother knows best: Plant knowledge key to childhood health in remote Amazon
6. 20-year study shows significant rise in childhood obesity, especially among girls
7. New study challenges critical period in childhood vision development
8. First clinical trial of gene therapy for childhood blindness
9. UN pours polio vaccine into Yemen amid outbreak
10. Billions of dollars saved in US by polio vaccination
11. Genome of deadly amoeba shows surprising complexity, evidence of lateral gene transfer

Post Your Comments:

(Date:6/16/2016)... FRANCISCO , June 16, 2016 ... size is expected to reach USD 1.83 ... by Grand View Research, Inc. Technological proliferation and ... banking applications are expected to drive the market ... ) , The development of advanced ...
(Date:6/9/2016)... , June 9, 2016 ... deploy Teleste,s video security solution to ensure the safety of ... during the major tournament Teleste, an ... systems and services, announced today that its video security solution ... to back up public safety across the country. The ...
(Date:6/2/2016)... 2016 The Department of Transport Management ... 44 million US Dollar project, for the , ... Personalization, Enrolment, and IT Infrastructure , to ... and implementation of Identity Management Solutions. Numerous renowned international vendors ... Decatur was selected for the most compliant and ...
Breaking Biology News(10 mins):
(Date:6/24/2016)... on a range of subjects including policies, debt and investment ... Speaking at a lecture to the Canadian Economics ... the country,s inflation target, which is set by both the ... "In certain areas there needs to be frequent ... not sit down and address strategy together?" He ...
(Date:6/23/2016)... WI (PRWEB) , ... June 23, 2016 , ... ... supplements, is pleased to announce the launch of their brand, UP4™ Probiotics, into ... for over 35 years, is proud to add Target to its list of ...
(Date:6/23/2016)... ... 2016 , ... Charm Sciences, Inc. is pleased to announce ... Research Institute approval 061601. , “This is another AOAC-RI approval of the Peel ... President of Regulatory and Industrial Affairs. “The Peel Plate methods perform comparably to ...
(Date:6/23/2016)... (PRWEB) , ... June 23, 2016 , ... STACS DNA ... Technical Leader at the Arkansas State Crime Laboratory, has joined STACS DNA as a ... STACS DNA team,” said Jocelyn Tremblay, President and COO of STACS DNA. “In further ...
Breaking Biology Technology: