Since his mother started showing signs of dementia some five years ago - forgetting simple things such as what she was going to cook or wear - life has not been the same for Mr T.S. Amarbir Singh, 45.
As her condition worsened to emotional outbursts and sleepless nights, the education manager gave up his job in 2014 to look after her.
Mr Singh said one of the worries of caring for his 83-year-old mother, who has now lost her ability to speak and is tube-fed, is not knowing if he is doing a good enough job.
His wife, Ms Gurmit Kaur Toor, 44, said: "Every day brought a new challenge. You basically had to find ways of coping and what you could do better."
Dealing with a dementia patient's behaviour and physical needs can be demanding, but caregivers also face the stress that they put on themselves, said researchers at Tan Tock Seng Hospital yesterday at a press conference to share their findings.
The self-appraisal can come from conscientiousness and a wish to do better, which can become feelings of inadequacy and self-criticism, and finally guilt and shame, said Dr Lim Wee Shiong, a senior consultant with the hospital's department of geriatric medicine.
Between 2012 and last year, researchers interviewed close to 300 pairs of caregivers and patients and found that between 40 per cent and 60 per cent experienced significant stress. Something that emerged was the "worry about performance", which has not been studied here, researchers said.
Only two of the 22 questions asked covered the topic of self-appraisal, and Dr Lim's team has started to research the issue more deeply, to provide early help for caregivers.
It is estimated that about one in 10 people over 60 here have dementia, but the number is expected to grow due to the greying population.
Mr Singh said he appreciated strangers who approached him when he was out with his mother. "They ask a simple question, 'How's your mum?', and they share their stories," he said.