According to the Alzheimer’s Association, among the top 10 leading causes of death in America, Alzheimer’s is the only disease with no prevention, no cure and no way to slow its progress. Alzheimer’s gets worse over time, posing increasingly greater challenges to daily life. To understand this widespread and life-changing illness, here is a basic guide to Alzheimer’s disease:

Alzheimer’s is a progressive disease marked by declining memory, thinking and learning skills. The Alzheimer’s Association reports that over five million people have Alzheimer’s nationwide. Both men and women can be diagnosed with Alzheimer’s, and while it is not a normal part of aging, it primarily affects the elderly. With the rare exception of early onset Alzheimer’s, the illness is mostly found in adults 65 years old and over.

The symptoms of Alzheimer’s vary widely in severity. There are a number of important warning signs, affecting primarily memory and thinking. An impaired memory may result in difficulty retaining recently learned information, misplacing objects, an inability to retrace steps, losing track of dates or places and finding familiar tasks more challenging. Symptoms that affect thinking include: difficulty planning or concentrating, poor judgment and challenges reading or determining distance. The effects of Alzheimer’s change over time, and its progress can be tracked along a seven-stage framework of symptoms. In addition to the cognitive symptoms, people with Alzheimer’s disease are also vulnerable to personality changes. These behavioral changes include irritability, anxiety and depression. More severe cases can result in anger and agitation, physical or verbal outbursts, restlessness, feelings of distress, hallucinations, delusions and sleep disturbances.

Alzheimer’s disease leads to brain atrophy, causing it to lose nerve cells and tissue. While there is no universally accepted cause for Alzheimer’s, researchers believe plaques and tangles play a huge role. Plaques are abnormal protein clusters that build up in the brain and block neural pathways. Tangles, or twisted protein fibers, also accumulate in the brain and cause damage. There are also risk factors that can make an individual more susceptible to Alzheimer’s, including age and family history. Alzheimer’s is significantly more likely to affect people over 65 years old and individuals with a parent, sibling or child who have had the disease.

There is no known cure for Alzheimer’s, and there is no way to slow down the overall progress of the disease. However, appropriate treatment can help alleviate the symptoms. For cognitive symptoms such as confusion and memory loss, the U.S. Food and Drug Administration has approved two types of medications: cholinesterase inhibitors and memantine. Cholinesterase inhibitors delay the degenerative process happening in the brain, while memantine regulates chemical activity. Caretakers should oversee the individual’s personal comfort, looking out for any sort of physical irritation, including hunger, bowel and bladder movements, fatigue and pain. People with Alzheimer’s benefit from a calm environment and, most importantly, a patient and compassionate caretaker.