London, Dec 13 (IANS): Regular use of antipsychotic drugs may increase the risk of mortality by 60 per cent among individuals with Alzheimer's disease, a study has shown.

Antipsychotics -- also known as neuroleptics or major tranquilisers -- are a class of medication primarily used to manage psychosis including delusions, hallucinations, paranoia or disordered thought.

The findings, led by researchers at University of Eastern Finland, showed that the use of two or more antipsychotic drugs concomitantly was associated with almost two times higher risk of mortality than monotherapy.

The risk was found to be the highest at the beginning of drug use and remained increasing in long-term use.

In the study, the researchers compared the risk of mortality between haloperidol and risperidone -- the most commonly used antipsychotic drugs.

The results showed that haloperidol was associated with highest risk of mortality. The use of higher doses of haloperidol and risperidone were associated with an increased risk of mortality compared with low-dose risperidone use.

For the study, the team investigated 27 per cent individuals out of 57,755 diagnosed with Alzheimer's disease from Finland between 2005 and 2011.

These persons started antipsychotic drug use during the follow-up and did not have history of a psychiatric disorder, and did not have active cancer at the start of follow-up.

The study confirms current recommendations that antipsychotic drugs should be used only for the most difficult behavioural symptoms of dementia, such as agitation and aggression, and the duration of use should be limited, said Marjaana Koponen, doctoral student at the University of Eastern Finland.

The lowest effective doses are recommended, and concomitant use of two or more antipsychotics should be avoided, Koponen added.

The results were published in the Journal of Alzheimer's Disease.