Parkinson's patients have a higher risk of injurious fall and hip fractures already 26 years before a diagnosis according to a new cohort study at Umeå University in Sweden. The patient group's higher proportion of fall-related injuries can partly be explained by reduced balance, which could be a significant early sign of illness. The results of the study have been published in the journal PLOS Medicine.
In a cohort study*, Swedish researchers at Umeå University have investigated if male patients with Parkinson's disease had low muscle strength in the arms already at the time of military enrolment in early adulthood. The study found a reduced muscular strength in the arms on average already 30 years prior to Parkinson's diagnosis. Based on these results, it was investigated if this reduced muscular strength also could be associated with an increased risk of injurious falls and hip fractures.
The results show that early changes manifested in a reduced muscular strength also seem to result in an increased risk of injurious falls and fractures several years before diagnosis. The correlation also shows signs of the gradual dysfunctional balance reactions and impaired mobility being present at a much earlier stage, although it has previously been thought to happen in relatively late stages of Parkinson's.
"We asked ourselves if fall-related injuries at an early age could be a warning sign of the deteriorating balance that is characteristic to Parkinson's disease," says Helena Nyström doctoral student at the Department of Community Medicine and Rehabilitation and co-author of the article.
"By investigating health data from registers, we could see a correlation between individuals who were later diagnosed with Parkinson's and who were more often involved in injurious falls. It was also shown that the higher risk of hip fractures could be measured more than two decades before the diagnosis," she continues.
Injurious falls are a serious health risk and hip fractures are a common contributing factor to early death among the older population. The risk of hip fractures are especially high in people with Parkinson's, something which is likely caused by reduced balance and incapability of rotating the body in the event of a fall in order to protect the hip.
Parkinson's disease, which breaks down specific nerve cells and is usually diagnosed at around the age of 70, has an insidious onset and at first mostly affects mobility and balance. Previous research has shown that the disease manifests itself early in various ways. Balance and muscular strength is negatively affected at a later stage.
The study examined health data from all Swedes who were 50 years or older in 2005 (N=3.3 million). Out of these, 24.412 were diagnosed with Parkinson's in the period of 1988-2012, and these individuals were matched against ten people each in the control group. Researchers found that 18 per cent of all Parkinson's patients (before diagnosis) and 11.5 per cent of controls had at least one fall-related injury.
*Reference: Gustafsson H, Aasly J, Strahle S, Nordstrom A, Nordstrom P. Low muscle strength in late adolescence and Parkinson disease later in life. Neurology. 2015;84(18):1862-9. Gustafsson H et al. Neurology 2015