February 18, 2005
Alzheimer's drug is found to speed up mental decline
By Nigel Hawkes
TWO drugs often prescribed for dementia are ineffective and one actually
speeds mental decline, a study has shown.
Quetiapine (sold as Seroquel) and rivastigmine (Exelon) are prescribed to
nearly half the patients with dementia in residential homes in Britain,
often for long periods. Patients are given the drugs to control behavioural
changes such as agitation, which are disturbing to them and make them more
difficult to look after.
But a trial in Newcastle has suggested that the drugs are ineffective and,
in the case of quetiapine, accelerate the progress of the disease. The
trial, funded by the Alzheimer’s Research Trust, involved 93 people with
Alzheimer’s living in care homes in Newcastle. It was led by Clive Ballard,
of the Institute of Psychiatry at King’s College London. The patients were
treated with quetiapine, rivastigmine or a placebo pill. Neither of the
groups given the active drugs showed any benefit in their agitation symptoms
over six months. Those given quetiapine showed a much more rapid decline in
mental capacities. A report published in the British Medical Journal says
that it should not be used to treat such patients.
The results will affect medical practice because in March last year the
Committee on Safety of Medicines said that the drugs risperidone and
olanzapine should not be prescribed for dementia because of an increased
risk of stroke.
Quetiapine was an alternative, but is now in question. Professor Ballard
said: “This research shows that quetiapine does not help with the agitation
experienced by some patients and that it accelerates cognitive decline.”
Rebecca Wood, chief executive of Alzheimer’s Research Trust, said: “Research
is severely underfunded and we desperately need to do more towards finding
effective treatments for both the symptoms and underlying disease.”
A Department of Health spokesman said last night: “In March 2004 the
Committee on Safety of Medicines advised that two antipsychotic drugs,
Risperidone and Olanzapine, should be used in the treatment of dementia
because of an increased risk of a stroke.”
Antidepressants do not increase the risk of suicide, three studies suggest.
They may, however, increase suicidal thoughts and attempts at suicide.
This comes after controversy on the safety of selective serotonin reuptake
inhibitors such as GlaxoSmithKline’s Seroxat. It has been accused of
concealing data about suicidal thoughts among teenagers taking Seroxat and
is being investigated by the Medicines and Healthcare Products Regulatory