The TREND study

 

TREND is the abbreviation for:

 

Tuebinger evaluation of Risk factors for Early detection of NeuroDegeneration

 

The occurrence of specific symptoms that allow the clinical diagnosis of Parkinson's and Alzheimer's disease is preceded by a long prodromal phase in which the neurodegenerative process leads to substantial neuronal loss. To enable an earlier disease-modulating or even neuroprotective therapy it is essential to identify, characterize and validate risk and prodromal markers for Parkinson’s and Alzheimer’s disease. 

 

Background information about the TREND study

 

Parkinson’s and Alzheimer’s disease are common severe and chronic diseases. The appearance of specific symptoms that allow the clinical diagnosis of Parkinson's and Alzheimer's disease is preceded by a long prodromal phase in which the neurodegenerative process leads to substantial neuronal loss. To date, it is not exactly known why and how this happens.

 

Symptoms as risk factors – early detection is very important

 The neurodegenerative process in the prodromal phase is associated with several symptoms that may indicate an increased risk for Parkinson’s or Alzheimer’s disease.

 

These symptoms include:

  •  Ultrasound abnormalities like substantia nigra hyperechogenicity as a vulnerability marker for Parkinson’s disease
  • Olfactory dysfunction
  • REM sleep behavior disorder (RBD), i.e. a loss of muscle atonia during otherwise intact REM sleep
  • current or recurring depression
  • early motor signs such as reduced arm swing or arrhythmic gait
  • autonomic dysfunctionThese may be markers for the prodromal state of these diseases but are not specific.

Thus, the majority of people with these symptoms will never develop Parkinson's or Alzheimer's disease.

 

Nevertheless, these clinical and imaging markers have previously been implicated in (early stages of) Parkinson's disease or dementia and, thus, assessment of these markers may indicate a risk for the development of these diseases. Therefore, these and other (bio-)markers are assessed regularly in the TREND study to evaluate their predictive value for a neurodegenerative disease.

 

Aims of the study

 

The major aim of the TREND study is to collect data concerning these markers BEFORE Parkinson’s and Alzheimer’s Disease is diagnosed. We believe that the insights we get will enable earlier intervention or even neuroprotective therapy in individuals at prodromal stages of these diseases. Therefore, approximately 1200 individuals with a specific risk profile (see below) aged over 50 years at baseline are assessed every two years with a comprehensive, mainly quantitative assessment battery.