When Mr Lim was diagnosed with young onset dementia in February - at the age of just 59 - he and his wife were at a loss as to how to deal with it.
Dementia typically occurs in people who are aged above 65, though the condition causing deteriorating mental faculties can develop earlier, sometimes as early as the age of 45.
With it can come a host of social and economic burdens, especially for people who are working and have families to support.
Last year, the National Neuroscience Institute (NNI) diagnosed 180 new cases of young onset dementia, up from 100 in 2013.
Of the NNI's 3,000 patients with cognitive impairment, 35 per cent over the last seven years have been diagnosed with young onset dementia.
Mr Jason Foo, chief executive of the Alzheimer's Disease Association (ADA), said: "When you are 75 or 80 and the doctor says you have dementia, you will probably be okay with it because you are old.
"But when you are 50, you get very depressed. A lot of them lose their jobs because they can't function at work any more."
The rise in the number of young onset dementia patients could be due to greater awareness among patients and doctors about dementia and its symptoms, so patients seek help and are diagnosed early, said Dr Nagaendran Kandiah, a senior consultant at the NNI.
More younger people could also be developing dementia because of the increased prevalence of chronic diseases that can result in strokes, which in turn can lead to vascular dementia, he said.
Such diseases, including diabetes, high cholesterol and high blood pressure, are becoming more common with unhealthy diets and sedentary lifestyles.
Doctors say young onset dementia has a lot to do with genetics as well, and they hope to identify the gene responsible for the disease, then use gene therapy as a form of intervention. To better understand young onset dementia, the NNI is embarking on a three-year study of 300 patients.
The study is being financed by a $1.5 million grant from the National Medical Research Council.
Apart from looking into the neuroimages and genetics of the patients, the study will invite their family members to participate so researchers can identify patterns.
It will be the first such study in South-east Asia, said Dr Nagaendran, who is its principal investigator.
Preliminary results are expected in the first half of next year.
To help caregivers and patients with young onset dementia cope, the NNI has partnered ADA to pilot a programme called Early Stimulation, Exercise and Emotional Support for Young Onset Dementia (Esteem).
Since December last year, six patients have been attending weekly three-hour sessions in which they take part in activities such as cooking, art and computer work to keep their minds active.
Caregivers go into a separate room where NNI staff give them advice and support.
Mr Foo said this helps to prevent younger dementia patients from feeling "out of place" at care centres with older patients .
Mr Lim's wife, a part-time saleswoman, started attending Esteem sessions last month with her husband and he has started to open up during the activities. She said: "At least I have a circle of friends who are in the same boat, whom I can exchange advice with. I can also accompany my husband and he has opened up during the sessions.
"Last month, he was putting sugar icing on a cookie and said he was doing it for our granddaughter, Amber."
This article was first published on April 25, 2015.
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