The dark is rising from the BBC World Service.

The powers of the dark are reaching out now steadily and stealthily all over this world.

Find out more at the end of this podcast.

Hello, I'm James Reynolds on the BBC World Service and this is BBC OS Conversations on Hope for Alzheimer's.

With a promising new drug on the horizon, we hear what it's like to care for loved ones, including parents, who gradually lose their memory and their speech because of the disease.

It's heartbreaking that I can't have those conversations and like sometimes I have dreams where he can talk.

But I have all the stories from when we were younger and my mum showing me photographs so that helps me kind of stay connected with him before Alzheimer's.

It is the most common cause of dementia.

Alzheimer's disease affects the brain and most of the older people.

As symptoms get increasingly worse, what might start off as just a few memory lapses or speech issues can end up with someone being unable to talk or even to recognise members.

According to the World Health Organization, around 55 million people across the world currently have dementia.

That number is expected to triple by 2050.

The disease has a huge impact on family.

We brought together three women in the UK and the US.

They have relatives with Alzheimer's.

For student Ginny, it's her grandmother.

For Maddie Elitz, her father, she cares for him full time.

And for Jillian, in Arizona, it's her mother.

Jillian began by describing when she first noticed that her mother might have a problem.

You know, it's always the little things at first.

It's not usually something really big, although that does happen for some people.

And for my mum, it was the little things.

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