It is not easy to say which is the cruellest of the thousand natural shocks that flesh is heir to, but in times of high and rising life expectancy most people would think of Alzheimer’s disease as being among the worst. It is a disease that probably agonises the sufferer’s close relatives more than sufferers themselves, for the burden on carers is immense – indeed, incalculable. Among the most terrible consequences of the disease is that memories of the demented person before his or her long decline are often pushed aside by those of the shell they become; and this being the case, one cannot help but wonder whether the increased life expectancy of people with Alzheimer’s disease is a blessing or a curse.

Oddly enough, Jay Ingram’s excellent and readable book about Alzheimer’s disease makes little reference to the burden on carers, being mainly concerned with the history and science of the disease. For the moment there is no light at the end of the tunnel, and by the time readers finish the book they will be fully aware of why this is so.

Alzheimer’s disease is named after the German psychiatrist and neuropathologist Alois Alzheimer, who first described its neuropathology early in the 20th century. A 51-year-old patient of his had experienced rapid cognitive decline, dying in his asylum four years later. Alzheimer examined her brain under the microscope using the latest techniques