The Under Secretary for Health, Libby Lee, on Saturday defended a government plan to allow doctors to impose mandatory detention orders on psychiatric patients with violent tendencies, even if they voluntarily seek hospital treatment.

Under the plan, such patients could also be given a conditional discharge order, which means they would have to reside in a certain place, take medicine as prescribed or attend follow-up sessions.

Community activists are concerned the changes could deter people with mental health problems from seeking medical help, but Lee said that will not be the case.

"We believe that it won't actually deter that many of mental patients from seeking help because [the changes] only cover those patients with severe violence behaviour or tendencies," she said.

"Even so, for the mental patients with violent behaviour or tendencies, not everyone requires conditional discharge. The medical team would do the assessment before their discharge and plan whether they need a discharge order or not."

The official added that without the conditional discharge mechanism, medical professionals may keep patients hospitalised for a longer period of time for safety's sake.

Separately, Lee said they plan to roll out the Chronic Disease Co-care Pilot Scheme in November at district health centres and participating private clinics.

The official said they want to identify patients aged 45 or above who did not know they had hypertension or diabetes and to allow them to seek treatment early through the government-subsidised programme.

Participants of the scheme will pay HK$120 for the screening.

Lee said the scheme will later include other chronic illnesses, like hepatitis.