Linton in Cambridgeshire is one of those English villages usually dubbed “historic”, and which now appear stranded on the edge of the 21st century. A dormitory village serving Cambridge and London, its main arterial road thunders towards Essex across the rumble strips at its entrance and exit. Off this, a warren of narrow lanes remains, a postcard arrangement of thatched cottages and inns leaning drunkenly over the pavements.

Andrew and Sarah King married in the local church in 1998. It was a rainy day and they were accompanied by a ballet of colourful umbrellas as they left St Mary’s for the reception at nearby Chilford Hall. Today, their guests make the usual observations about the obvious happiness of the bride and groom that day, and recall their hopes and wishes. Sarah King remembers her husband digging out the pond in their small back garden on the estate where they began married life, and where they remain. Andrew King, though, is not able to reminisce about this, or, indeed, about many of the significant events in his past. Ask him how long he has been married and Andrew replies with the practised timing of someone who has always enjoyed raising a laugh, “Too long”. He casts a smile across at Sarah as he says this. On a good day, the repartee between them gives you a very clear idea of how things were. It is also a testament to the quality of Andrew’s intellect that he will often bat back a facetious reply that covers his inability to answer with factual accuracy.

Last year, at the age of 43, Andrew was diagnosed with early onset dementia (EOD), the term used to describe those who develop the illness before they reach the age of 65. As with dementia in older people, the enemy comes with various names – Alzheimer’s disease, vascular dementia, Pick’s disease, to name but a few – which differentiate between the area of the brain in which the degeneration begins, or the cause. All have in common a progressive impairment of memory, speech and understanding. All are incurable. Early onset dementia generally mirrors “ordinary” dementia, except that it appears to be more aggressive. There are some 50,000 cases in the UK, according to John Hodges, professor of behavioural neurology at Cambridge University.

Andrew King was – still thinks of himself as – a scientist. A geneticist, he researched in the fields of muscular dystrophy and motor neurone disease. In 1995, he came to work for the Wellcome Trust Sanger Institute at the Genome Campus near Cambridge, part of the team that raced to unlock the secrets of human DNA. His subsequent diagnosis is a particular and bitter irony to him. In July last year, he was told he was suffering from Pick’s disease (frontotemporal dementia). In November, he and Sarah were called to Addenbrooke’s (the Cambridge University Hospital) for a second consultation at which it was revealed that, in fact, he was suffering from a form of Alzheimer’s that is caused by a genetic abnormality. His life expectancy is placed at five to eight years.

Andrew is currently taking Aricept, one of the new drugs that affect the disease’s symptoms, and that the National Institute for Clinical Excellence (NICE), the government body deciding on treatments available on the NHS, recently denied to patients with mild dementia in England and Wales. The Alzheimer’s Society says that younger people with EOD are being affected by NICE’s controversial decision, which comes at a time of phenomenal growth in global research. A new generation of drugs that will alter the actual pathology of the disease is around the corner. Promising research is also being done into immune therapies – vaccinations that encourage the system to break down the protein build-up in the brain that is typical of Alzheimer’s. Professor Hodges believes there will be a major breakthrough before he retires. He is 55.

Andrew King left the Sanger Institute in 2004 after his work deteriorated. At that stage it was thought that his confusion was caused by depression (early onset dementia is frequently misdiagnosed). He therefore applied for other jobs in his own field but without luck, and ended up working at Tesco. The Sanger Institute has just released his pension. Many people with EOD have difficulty persuading former employers that the standard retirement age should not apply to them. It is another irony that those suffering from a condition usually associated with old age may be unable to access their old age pension.

So you might say that Andrew King is “lucky” – lucky in comparison with most of those with EOD. Living in Cambridge, he attends one of the country’s few centres of excellence in the field, the Memory Clinic at Addenbrooke’s. In addition, the area is served by a dedicated young-onset co-ordinator, Lynne Macdonald. While most younger

people with dementia find that any services are aimed at much older people, Andrew now spends Mondays at a day centre and Friday afternoons at a pottery workshop, both dedicated to those with EOD. Sarah King says such groups have transformed him. For a period he was withdrawn and distant, but he is once again demonstrative towards her. “They have given me my husband back,” is how she phrases it.

“No one who is not or has not been a carer can imagine what it is like,” one Alzheimer’s Society official says. In mid-life, the stresses are proven through research to be greater. During the course of researching this feature, I spent a morning a week at a local Alzheimer’s Society art group. “Go behind the door!” one EOD carer begged me. There was a general feeling that the media depiction of Alzheimer’s doesn’t cover the half of it. The Alzheimer’s Society summarises, “It is hard to imagine another illness where one diagnosis affects so many people, so keenly, as early onset dementia.”

Andrew King, 44

I’d always wanted to be a vet and my big regret in life is that my A-level results weren’t good enough. Instead, I worked in genetics. But things started going wrong. I began to feel I couldn’t do some of the things I used to manage easily. I was worried something serious was wrong. I thought it might be Parkinson’s because my dad had Parkinson’s. But I didn’t say anything to Sarah.

I had to leave the Sanger and I worked at Tesco for three years, pushing trolleys. It was getting out of the house and getting some money in. The worst thing was when I lost that job, too, and I was just here, inside these four walls. I had lost control of my life.

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