The most common type of dementia. A progressive disease beginning with mild memory loss possibly leading to loss of the ability to carry on a conversation and respond to the environment. Involves parts of the brain that control thought, memory, and language. Can seriously affect a person’s ability to carry out daily activities.

Dementia is a syndrome – usually of a chronic or progressive nature  in which there is deterioration in cognitive function (i.e. the ability to process thought) beyond what might be expected from normal ageing. It affects memory, thinking, orientation, comprehension, calculation, learning capacity, language, and judgement. Consciousness is not affected. The impairment in cognitive function is commonly accompanied, and occasionally preceded, by deterioration in emotional control, social behaviour, or motivation.

Dementia results from a variety of diseases and injuries that primarily or secondarily affect the brain, such as Alzheimer's disease or stroke.

Alzheimer’s disease is an irreversible, progressive brain disorder that slowly destroys memory and thinking skills, and, eventually, the ability to carry out the simplest tasks. In most people with Alzheimer’s, symptoms first appear in their mid-60s. Estimates vary, but experts suggest that more than 5.5 million Americans, most of them age 65 or older, may have dementia caused by Alzheimer’s. This number is projected to nearly triple to 14 million people by 2060.

Scientists do not yet fully understand what causes Alzheimer’s disease. There probably is not one single cause, but several factors that affect each person differently.

• Age is the best known risk factor for Alzheimer’s disease.
• Family history—researchers believe that genetics may play a role in developing Alzheimer’s disease.
• Changes in the brain can begin years before the first symptoms appear.
• Researchers are studying whether education, diet, and environment play a role in developing Alzheimer’s disease.
• Scientists are finding more evidence that some of the risk factors for heart disease and stroke, such as high blood pressure and high cholesterol may also increase the risk of Alzheimer’s

    How Alzheimer’s disease treated?

Alzheimer’s disease is complex, and it is unlikely that any one drug or other intervention can successfully treat it. Current approaches focus on helping people maintain mental function, manage behavioral symptoms, and slow down certain problems, such as memory loss. Researchers hope to develop therapies targeting specific genetic, molecular, and cellular mechanisms so that the actual underlying cause of the disease can be stopped or prevented.

Billions of dollars have been invested in the industry and a successful, marketable treatment would likely make a fortune for the company which gets there first.

MORE THAN 150 TRIALS HAVE FAILED IN 20 YEARS

Between 1998 and 2017 there were around 146 failed attempts to develop Alzheimer's drugs, according to science news website, BioSpace. 

 HOPE:

China approves world’s first new Alzheimer’s

The world’s first new drug for the treatment of Alzheimer’s disease in nearly two decades – and perhaps the only treatment with the potential to reverse the condition – was approved by the Chinese government. The National Medical Products Administration said the drug, Oligomannate, had been approved for the treatment of “mild to moderate Alzheimer’s disease and improving cognitive function”.

In preclinical studies, the drug demonstrated the ability to block the abnormal rise in intestinal flora metabolites, regulate peripheral and central inflammation, decrease deposition of amyloid protein and tau hyperphosphorylation and improve cognitive function. Green Valley plans to launch the drug in China by the end of the year. Early next year, the company intends to conduct a global Phase III clinical trial in the US, Europe and Asia to support regulatory submissions worldwide.

Over the past two decades pharmaceutical companies have invested hundreds of billions of US dollars and brought more than 320 candidate drugs to clinical trial. Only five were approved for clinical use to relieve symptoms, and none could stop the brain cells from withering away. Due to repeated costly failures, Alzheimer’s-related programmes have been terminated in many large medical companies.

A major challenge for the Chinese research team was to explain the mechanism, with authorities reluctant to approve a new drug unless researchers could explain exactly why it worked. There were many theories on the causes of Alzheimer’s, but none seemed to apply to the drug.

Source: edition.cnn.com, scmp.com, pharmaceutical-technology.com, who.int, dailymail.co.uk, nia.nih.gov, cdc.gov