It is very disconcerting that only 2 per cent of the resident population here in Singapore donated blood last year (Drive to get more young blood to donate; Dec 24).

It is a trend that is most likely to continue, if not worsen, if the problem is not tackled.

What makes the situation more serious is that the demand for blood from hospitals looks set to grow with the population greying.

Also, it may get increasingly difficult to maintain a pool of eligible blood donors in future.

The eligibility criteria include a stipulation that a blood donor must not be on prescription drugs for any illnesses - which could include high blood pressure, diabetes - and for mental illnesses like depression and anxiety disorders.

There are reports that one in four people here would be affected by a mental illness in his lifetime.

If most of them subsequently took prescribed medication for their condition, it would mean that more would be barred from donating blood during their course of treatment. And their treatment could be life long.

This could mean even fewer donors in the pool in the long run.

A study carried out by the Institute of Mental Health (IMH) in 2010 found that many people with mental illnesses also have a physical illness, such as diabetes and high blood pressure (IMH launches nationwide study to gauge mental health of adults in Singapore; Oct 12, 2016).

A comparison with a second study should show whether the percentage of people with mental illnesses is increasing. And if the number is indeed going up, and more people are seeking psychiatric help, the authorities may need to look at other strategies to get more blood donors.

But I hope the day will not come when Singapore would have to resort to compulsory blood donation.

Lee Kay Yan