Did you see the news last December that Terry Pratchett has Alzheimer's. He is only 59. When I was younger, we used to congratulate anyone who approached their sixtieth birthday without dying. Now, with the improvements in diet and medical science, we all expect to live a lot longer. This is all a little double-edged.

As I grow older, one of the things I fear is that my mind may die before my body. There is nothing more depressing than watching your own personality disappear, leaving nothing but apparently immortal flesh behind. As an interested spectator, I have had relatives who sat or lay like vegetables in nursing homes for several years while we all waited for them to die. Which makes the anecdotal point that depression affects many when they are diagnosed with Alzheimer's. As the disease progresses, depression also spreads to the immediate carers in the family, other relatives and friends. Perhaps we carers should all be reaching for the Zoloft.

The clinical evidence suggests that about 25% of people with Alzheimer's suffer persistent depression, although there are no formal studies that map the relationship between the two. What we can say is that, when it arises, depression significantly affects the quality of life for all involved. Patients can be more quickly shuffled off into a nursing home or there is a risk of suicide by any of those involved.

The research links serotonin and the neurotransmitter systems with depression, but the evidence for the use of Zoloft and other Selective Serotonin Reuptake Inhibitors (SSRIs) in the treatment of those with Alzheimer's has been patchy. Part of the problem is in assembling statistically significant sized groups of participants with broadly similar levels of symptoms (from mild to demented). The other problem is money. In the UK, there are about 700,000 people with Alzheimer's, but only £10 per patient is spent each year on research into the disease - less than 5% of the amount spent on research into cancer. However, in Arch Gen Psychiatry, Jul 2003 there was a slightly better attempt made to test the safety and effectiveness of for both the person with Alzheimer's and, indirectly, for the caregivers. This was a 12-week randomised, placebo-controlled trial.

The first piece of good news was that the intellectual level of people diagnosed with Alzheimer's who received Zoloft remained relatively stable, whereas the placebo group declined. However, there is a problem in that the evaluations were based on the caregivers' reports and their expectations (and hopes) may have played a part in skewing the results. Nevertheless, the finding is interesting. There were few side effects in those who took the Zoloft.

The second piece of good news is that Zoloft did reduce the depression experienced by the Alzheimer's patient and this significantly relieved caregiver distress. Given that private care is usually of a better quality than institutional care, this is a major step forward. It also has significantly economic implications for the state that may otherwise have to subsidise long-term care in an institutional home or hospital. Those receiving the Zoloft were less likely to wander around, or become agitated or aggressive. If confirmed in continuing trials, such behavioural improvements will mean that caregivers can continue to give personalised and individualised care for longer. This may slow the loss of personality and lessen the burden of guilt when the patient is finally sent into an institution.

So should all of us Baby Boomers reach for the Zoloft if we feel ourselves slipping away or bulk buy Zoloft for distribution to our potential caregivers? Well, this research is simply a useful indicator. There are many difficulties in relying on one set of findings to give generalised advice. I suppose that is the benefit of continuing research. So long as it delivers good news before we die, of course.