As the disease progresses, more amyloid plaque builds up on the neurons causing increased atrophy of the cerebral cortex. Additionally, the decrease in the production of the neurotransmitters necessary to transmit the messages of mood and memory continues. As the production of dopamine decreases, behavioral problems begin to manifest. The ability to have fluid muscle movement also declines as the loss of both gross motor and fine motor movement becomes noticeable. In addition, the deterioration and tangling of the neurons make it more difficult for any messages to be transmitted and received.
The hallmark of the Middle-Stage of the disease is therefore marked functional loss in the individual. Increasing memory loss causes problems with the sequencing of ADLs along with perceptual-motor problems exhibited with the decline of both gross motor and fine motor skills. With the decrease of available dopamine, serotonin, and acetylcholine in the brain, behavior problems (often called “positive symptoms”) begin to appear such as wandering, agitation, vocal outbursts, and sleep disturbances which require more intensive supervision and care. Delusions (often paranoid) and hallucinations may also occur.
Although medications are available to treat these disorders, antidepressants, antipsychotics, and sedatives all have side effects and can interact with other medications. Thus non-drug interventions should be attempted before resorting to medications. If the decision is made to treat pharmacologically, some physicians may order what is known as a “typical” neuroleptic, such as Haldol, though the atypical antipsychotics which include risperidone (Risperidol), quetiapine (Seroquel), olanzepine (Zyprexa), aripiprazole (Abilify), and ziprasidone (Geodon) may be better tolerated than the more traditional agents. They also tend to have fewer extrapyramidal symptoms which can cause a cumulative effect in the individual over time.
Benzodiazepines typically used to modify and treat anxiety are known to impair memory function. Their pharmacological effect is quite similar to alcohol since they are known to alter the GABAergic receptors in the brain. Individuals with Alzheimer’s disease often become more confused when taking benzodiazepines, and are at an increased risk of falling. Often the antipsychotics are much better at treating anxiety since the behavior is usually related to a sense of fear or lack of control that the individual is experiencing secondary to the decreased dopamine production in the brain.
Since functional losses and behavioral issues occur in the Middle Stage of the disease, this is the most common time when families begin to seek medical intervention or assistance with their loved one. At this stage the person may become incontinent and their sleep cycle may be disturbed (up at night, sleeping during the day). Personality and emotional changes become more pronounced and the caregiver simply becomes overwhelmed.