Alzheimer's disease is often called the epidemic of the 21st century with more than 55 million people worldwide living with dementia, according to the World Health Organization (WHO), and that number is estimated to reach 139 million by 2050. Every year, thousands of people die globally due to the disease, a medical condition that causes memory loss or dementia, and a general decline in cognitive functions due to the death of brain cells over time.

Alzheimer's disease is the most common type of dementia, according to the U.S. Centers for Disease Control and Prevention (CDC).

"Dementia means loss of cognitive function. The most common reason disease for this loss is an accumulation of certain substances in the brain (mostly amyloid and tau); these are Alzheimer’s changes. So, a more correct term is dementia of the Alzheimer’s type," Nikolaos Scarmeas, a professor of neurology at the Medical School of the University of Athens, told Anadolu Agency (AA).

The exact causes of the disease are not known however, genetic factors and age are considered to be some of the main ones, Sofia Kanellopoulou, a health psychologist at the day care center of the Athens Alzheimer’s Association, told AA.

Recently, there have been studies that link the disease with high cholesterol, diabetes, hypertension, obesity and smoking.

However, Scarmeas said: "The cholesterol problem is quite complex. There are some studies that suggest that problems with cholesterol at midage may play a role in dementia at old age. But there has been no proven preventive effectiveness of cholesterol-lowering drugs so far."

More than 60% of Alzheimer's patients live in low- and middle-income countries, and 10 million new cases are added each year.

There is no known definitive treatment method for the disease, which is defined as a neurodegenerative disorder accompanied by neuropsychiatric symptoms and behavioral changes characterized by a decrease in daily activities and deterioration in cognitive abilities.

According to the WHO, Alzheimer's disease is the seventh most common reason of death worldwide, and the number of patients is forecast to nearly triple by 2050.

Scientific progress

Since the early discovery of the disease by German psychiatrist Alois Alzheimer in 1901, a lot of progress has been made and scientists and researchers are optimistic that the path to its cure might be on the way.

"There are quite a few drugs being tested in Phase 3 studies," Scarmeas said.

Earlier this year, an additional 42 genes were discovered that scientists linked to the development of the disease.

The most significant discovery was the MGMT gene, which scientists linked to the development of the disease in women making them more susceptible to developing Alzheimer's than men.

"It has been known for a long time that the disease is more common for women compared to men. There are many potential reasons for this including the loss of hormonal protection post-menopause, the longer life expectancy, etc. Maybe there are additional genetic reasons," Scarmeas said.

In recent years, other types of treatment were also used worldwide mostly for patients who are in the initial or middle stage of the disease and are applied in combination with medication.

Such treatments might include mental empowerment, speech therapy, occupational therapy, art therapy and physical exercise.

"Much funding has been funneled to dementia research since this is a major public health problem," Scarmeas said, adding that "much better therapeutic tools in the future" will be available.

Living with it

There are usually three stages of the disease – early, mid and advanced. In the advanced stage, patients are completely unable to communicate with the environment and are 100% dependent on their caregivers.

A woman in her late 60s has been living with Alzheimer’s for the past five years. Her husband George Pano said that the progress of the disease is somewhat slow, but changes have developed in the patient’s daily routine.

"She repeats herself several times, she forgets answers just a few seconds later," Pano said.

"My biggest fear is that the time will come when she would not be able to recognize our children and our grandchildren or even me," he said, adding, "It will be a nightmare."

"Caring for family members that suffer from dementia or Alzheimer’s could be stressful," Kanellopoulou said.

Katerina, 53, takes care of her 78-year-old mother suffering from an advanced stage of Alzheimer's.

"It is a very difficult task," she said.

"There are times that she asks to go visit her parents and her husband; they are all dead," Katerina told AA with an obviously distressed tone.

"It is the worst thing to see that someone you love and care about is unable to recognize you. I sometimes cannot handle it," she added.

"The emotional burden is very important as caregivers are more likely to be depressed, they tend to increase the use of psychotropic medicines and visit doctors more often ... They do not sleep well and feel exhausted. The constant anxiety is a particularly aggravating factor," Kanellopoulou said.

In Greece only, according to Athens Alzheimer's Association, there are 200,000 people suffering from dementia and 280,000 people from a mild mental disorder that is a precursor to dementia, while there are around 400,000 caregivers dealing with patients suffering from it.

Although the country has devised a national action plan for dementia and Alzheimer's disease and there are memory clinics and day care centers mostly in the large cities of Greece, services are still significantly inadequate.