A new medical study has raised concerns that attendance at Mass by elderly people could increase their chances of experiencing an episode of fainting.
Researchers at University Hospital Limerick claim the multiple sudden changes in position during Mass from sitting to kneeling to standing can trigger a lowering of blood pressure that can result in fainting.
It found there was an average of 15 different movements between sitting, standing, kneeling and walking to Communion during a typical Sunday Mass which lasted around 34 minutes and involved standing for over 15 minutes.
Researchers noted services such as marriages, funerals or religious ceremonies at Easter and Christmas often lasted even longer, with longer episodes of standing and more frequent changes of posture.
The study has recommended that consideration should be given as to whether it is safe for older Mass-goers to be subject to such significant stress that comes from movement to an upright posture.
The study, published in the 'Irish Medical Journal', examined the link between Mass attendance and syncope - the medical term for fainting which involves a temporary loss of consciousness that is usually linked to an insufficient flow of blood to the brain.
Fainting is common and accounts for up to 2pc of all presentations in hospital emergency departments annually.
The study said orthostatic hypotension (OH) - a lowering of blood pressure that occurs within three minutes of standing or from tilting the head - is recognised as a common cause of fainting.
It noted the 2016 Census showed over 78pc of people still identified themselves as Catholic while daily or weekly Mass attendance is common throughout the country.
One of the main authors of the report, Dr Maria Costello, of the UL Hospital Group's Department of Ageing and Therapeutics, said Mass attendance involved multiple changes of position including standing up to 10 times during a ceremony with stationary standing episodes occurring for up to four minutes at a time.
"We suspect that the sudden change in position can precipitate an episode of OH in vulnerable individuals," said Dr Costello.
Researchers identified 110 cases of patients with situational syncope with 56.2pc of incidents occurring at Mass.
Almost three out of every five of these fainting episodes were experienced by females. The median age was 74 years.
Over a quarter of those who had fainted at Mass had OH confirmed.
The next most comment situations were undefined bathroom-related activities followed by urinating, coughing and laughing.
Dr Costello claimed Mass- goers may also have other environmental triggers including multiple layers of clothing and some might fast prior to receiving a communion host which could increase their risk of fainting.
"Consideration should be given as to whether it is safe for older Mass-goers to be subjected to such significant orthostatic stress," she added.