Loss of the sense smell often precedes major symptoms Alzheimer disease and Parkinson What additional information is needed to use this association prevent or treat these disease?

While loss of the sense of smell (anosmia) is indeed associated with an increased risk of developing Alzheimer's disease and Parkinson's disease, additional information is needed before the association can be directly used for prevention or treatment of these diseases. Here are several key pieces of information that would be necessary:

1. Determine the causal relationship: Establishing a causal link between loss of smell and the neurodegenerative diseases is crucial. Although studies have shown a correlation, it is unclear whether anosmia is a risk factor, an early symptom, or a consequence of these diseases. Further research, such as longitudinal studies and experimental models, is needed to determine the directionality of the relationship.

2. Identify the underlying mechanisms: Understanding the biological mechanisms connecting loss of smell and neurodegeneration is critical. Research should aim to investigate the olfactory system's role in the development and progression of Alzheimer's and Parkinson's diseases. This may involve studying the neural pathways, neurotransmitter systems, and molecular changes associated with both conditions.

3. Develop early detection methods: If anosmia proves to be a reliable early indicator of neurodegenerative diseases, it becomes essential to develop effective methods for early detection and diagnosis. This could involve creating standardized smell tests, wearable sensors, or other innovative approaches to assess olfactory function accurately and conveniently.

4. Explore potential interventions: Based on the underlying mechanisms, researchers can investigate potential interventions to prevent or treat the neurodegenerative diseases associated with loss of smell. This could include olfactory training, intranasal therapies, or other strategies aimed at improving or compensating for olfactory dysfunction.

5. Assess the predictive value: Long-term studies are necessary to determine the predictive value of anosmia in identifying individuals at high risk of developing neurodegenerative diseases. This can involve following cohorts of individuals with anosmia over time to assess their rates of disease development and progression.

By addressing these key areas of research, scientists and clinicians can work toward using the association between loss of smell and neurodegenerative diseases for the prevention, early diagnosis, and effective treatment of conditions like Alzheimer's disease and Parkinson's disease.