Alzheimer's disease (AD) and Parkinson's disease (PD)

In general, Alzheimer's disease (AD) and Parkinson's disease (PD) are thought to be separate infections with unique symptoms. However, new research indicates that the illnesses share nearly all clinical and neuropathological aspects to a large extent. A reasonable amount of AD patients, for example, exhibit problems such as persistent spasms and muscle contractions, which are also indications of Parkinson's disease. On the other hand, many Parkinson's disease patients acquire dementia, which is linked to Alzheimer's disease. This paper basically describes in depth why Alzheimer's disease and Parkinson's disease are separate neurological illnesses despite having many similarities.  Effects of Parkinson's disease and Alzheimer’s disease to the brain

Scientifically, any effects or motor skills disorders are linked to brain failure to some extent (Stratton, 1994). Parkinson's disease has therefore been proven to have some impact on the brain and its structure. The brain damage caused by the infection usually is the leading cause of health deterioration among the patients suffering from the infection. The disease is characterized by a slow but progressive degenerative disorder affecting specific parts of the central nervous system which include the brain and spinal cord (Carlson, 1994). Tremor characterizes the disease at a time when the muscles are at rest. At times, increased muscle tone is witnessed (Plaha, 2005).

Parkinson’s disease also slows down the action of the brain to the extent that the victim experiences a slowdown of the voluntary movements and faces difficulty in maintaining balance also termed as postural instability (Bond, 2000). Statistics also show that most people suffer impaired thinking capacity and at advanced stages, dementia which is also associated with, Alzheimer’s disease. The disease is known to cause the degeneration of nerve cell which is part of the basal ganglia which are often referred to as substantia nigra (Forno, 1981).

The basal ganglia are part of the nerve cells which help in smoothening out the movement of muscles movements and coordination of the changes in body posture. Each time the brain initiates an impulse to move a muscle, for example, lifting an arm, impulse passes through the basal ganglia. The basal ganglia contain nerve cells which release neurotransmitters which trigger the next nerve cell in the pathway to send impulse (Heimer, 1983). The key neurotransmitter, in this case, is referred to as dopamine. Degeneration of nerve cells in the basal ganglia results in the production of less dopamine hence the connections between nerve cells decreases. The final result is that the basal ganglia do not perform its smoothening action resulting in muscle dysfunction (Wickens, 1990).

Statistically, Parkinson has been proven to be the second among the most common degenerative disorders of the central nervous system after the Alzheimer disease. Approximately affects 1 of 250 people older than the age of 40 and 1 out of 100 people older than 65 and about 1 out of 10 people above the age of 80 (Reijnders, 2008).It has also been found that the disease begins at the ages of 50 and 79 years of age and mostly occurs in children and adolescents. The disorders can be diagnosed through a doctor's evaluation, magnetic resonance imaging and computed tomography (Singh, 2007).

Risk factors associated with Parkinson's and Alzheimer’s disease

Some of the environmental factors that contribute to the contraction of the infections are the use of some specific pesticides, high cholesterol levels in middle age and hyperhomocysteinemia (Betarbet, 2000). Tobacco use, traumatic brain injury and depression are also some of the factors that make one susceptible to infection. Genetically, there is insufficient evidence to back up the claims that milk consumption among the men, chronic anemia, and high iron intake also pose a higher risk of infection (Park, 2005). Some sources also suggest that high intakes of aluminum mostly through drinking water also puts one at high risk (Flaten, 2001).

Recent studies also indicate that exposure to excessive electromagnetic fields, especially from electrical grids, also causes development of the disease (Johansen, 2000). Other proven causes are excessive alcohol input, obesity during middle age and chronic anemia (Zawora, 2009). There are also some factors that lower the risk of one becoming a victim of the infection.Research shows that physical exercise, coffee intake, and hyperuricemia play a significant role in prevention (Crizzle, 2006). Low tobacco intake, moderate alcohol consumption, and increased vitamin E intake have also been proven to be possible factors which may also reduce the risk of one contracting the disease (Liou, 1997).

Excessive exposure to some solvents may also lead to neurological disorders’ research conducted using the magnetic resonance spectroscopy approach concluded that a lot of neural damage is caused in the lentiform nucleus in people exposed to very high levels of hydrocarbonates (Grandjean, 2014). It has however been noted that most of the epidemiological studies and research have failed to show the occupational exposure to solvents and risk of Alzheimer's and Parkinson's disease. Scientific research has also proven that diet also plays a key role in prevention of the infections. For instance, Mediterranean diet has been known to reduce the risk of contraction.Omega 3 fatty acids are also key in as far as neuroprotection is concerned (Zhao, 2009).

Similarities of Alzheimer’s disease and Parkinson’s disease

Both Alzheimer’s disease and Parkinson’s disease have common cognitive decline although it is to some extent less common in Parkinson’s disease (Janvin, 2006). The cognitive decline also referred to as mild cognitive impairment (MCI), refers to the slight but noticeable deterioration in one's cognitive abilities (Gauthier, 2006). Among the factors under observation and measurement are memory and thinking abilities, motor skill among many others. Skills. Evidence suggests that a victim suffering from MCI stands a higher chance of developing Alzheimer's or another dementia (Draper, 2013). Statistically, approximately a half of the people with PD develop cognitive difficulties, in the long run, these problems range from mild forgetfulness to full-blown dementia.

Subcortical is the name given to dementia developed by patients who have Parkinson's disease (Leentjens, 2008).It is given the name because it affects the area of the brain located close to the subcortical region. And also because the clinical symptoms of subcortical dementias differ from the signs of the cortical dementias which occurs in patients with Alzheimer’s disease. In as much as the two have similar cognitive decline, PD dementia is characterized by a slowdown in physical activity which is often accompanied by slow thinking.However, the memory response in PD patients is better than the response in AD patients their memory retrieval is better (Rabins, 2006).

Patients suffering from both infections also display some behavioral symptoms. One of such signs is depression. In some cases, the tendency of the victims to portray similar behaviors makes it a bit difficult to distinguish which of the infection they are suffering from. It is, however, vital to conduct a more in-depth scrutiny to ascertain the kind of disease to come up with the correct prescription and provide proper management and care. Most often, the depression as a result of PD is responsive to antidepressant treatment more than that of AD.However, precaution should be taken not to overlook the fact that symptom-reducing therapy of PD easier which may lead to failure of doing it in time (Remy, 2005).

Another similarity in both cases is anxiety. It is counted among the most important causes of morbidity. Statistical estimates show that about 40% of patients with Alzheimer’s disease and Parkinson’s disease experience anxiety to a substantial level speaking of which the epidemiology is higher than normally expected especially among the older population. In addition to this, it’s also worrying that the age at which the onset of anxiety occurs at a later stage than expected basing on the data regarding the natural causes of anxiety .the phenomenon being common in both AD and PD requires behavioral treatment and administration of antidepressant or anti-anxiety medication as may be prescribed by the physician (Menza, 1993).

Both diseases are also characterized by the occurrence of Psychotic Symptoms. Psychosis is a disorder which is associated with patients having difficulties interacting with the reality (Chaudhuri, 2006). Victims suffering from the disorder often experience hallucinations or delusions. In both AD and PD patients, the symptoms may be an indication of delirium which is usually caused by infection or other known medical conditions. It is also key to note that in some Parkinson's disease patients, the risk of psychotic symptoms may be increased by the medication administered. However, if the drugs are administered at higher doses, they can induce hallucinations and ideas which are paranoid to some extent. Great care should be taken for patients suffering from psychosis because at times the experiences can be frightening and may cause them to hurt themselves or others (Fish, 2007).

Finally, Patients suffering from both disorders suffer from sleep disturbances. As the diseases advances, the quality of sleep in the patients deteriorates with the patients experiencing fragmented sleep. Parkinson’s disease patients experience a disorder known as rapid eye movement abbreviated as (REM).It is characterized by the occurrence of physical activity during the period of REM sleep when the victim is motionless. However, the good news is that the disorder has been proven to be responsive to treatment.Clonazepam is a medication to be avoided in patients with AD as advised by the medical experts since it has a big effect on their memory and alertness.

It is important to note that both AD and PD are as result of the destruction of the brain cells. Alzheimer’s disease is characterized by the destruction of brain cells resulting into the overall effect of the infection on the entire body and motor skills (Braak, 2003). Parkinson’s disease unlike AD, in which plaques and tangles are found is associated with loss of cells that produce dopamine, which is a neurotransmitter involved in nerve cell communication and carries out important transportation functions in the brain. The brain also contains cells in the substantia nigra which normally are involved in the collection of proteins known as Lewy bodies.

As older people advance in age, they tend to develop symptoms about movement which is in a great way identical to those of Parkinson's after, or just shortly before they develop developing cognitive difficulties which relate to Alzheimer’s disease. Over time, study shows that such similar combination of movement and cognitive changes is a symptom of a disease which is regarded as the second type of dementia known as Lewy Body Dementia (LBD) (McKeith, 2004).LBD is a progressive brain disorder marked by the buildup of abnormal protein deposits in areas of the brain whose main duty is to regulate behavior, movement, and cognition.

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