It revealed 10.8 per cent of city residents had a mental health condition, which is above the state average of 8.8 per cent.

Let's Talk co-founder John Parkinson said it was a troubling trend.

He said he was concerned people experiencing a high level of stress, anxiety or depression were failing to seek help.

"We have a lot of services available to help people but people aren't accessing them," Mr Parkinson said.

He is extremely concerned at least 12 people had died by suicide in the south-west since December.

"It's really concerning," Mr Parkinson said.

"We really need to reflect on our lives and make adjustments where necessary."

Mr Parkinson said he believed too many people ignored symptoms.

"It always comes back to the stigma - people think 'it will be better tomorrow'."

Mr Parkison said Let's Talk was committed to changing attitudes about mental health conditions.

"People need to talk - to ventilate their fears and worries," he said.

"We know through research and evidence that the more you keep it to yourself, the higher the risk is you will develop symptoms.

"We're totally committed to trying to ensure people are far more open and honest with others around them.

"People want to help, but you've got to let them in."

South West Healthcare's acting executive director of mental health Jodi Bateman also weighed in on the high rates.

"In general I would say the pandemic has impacted social determinants of mental health such as our connection to others, our routines, our contact with protective institutions like schools and our ability to do the things we would normally enjoy," she said.

"Cost of living, food security, loss of financial benefits and unstable employment that are an indirect result of the pandemic and also lead to increased stress and vulnerability to mental health problems.

"A sense of isolation can be felt increasingly as you move out into regional and rural locations.

"I would encourage people to re-establish their meaningful connections to other people and reach out for support if their mental health is impacted."

The census data also revealed a higher number of Warrnambool residents - 9.8 per cent - were suffering from arthritis, while the rate of asthma (10.8 per cent) was also higher than the state average of 8.4 per cent.

The rate of heart disease in the city was 5 per cent, which was higher than the state average of 3.7 per cent.

A South West Healthcare spokeswoman said the higher rates could be due to a number of factors.

"In general we do know that contributing factors would be many and varied, we know that people are living longer and the older you are the higher the likelihood that you may develop a chronic health condition," she said.

"Earlier diagnosis may have contributed to the increased numbers, as people have more awareness of health conditions and clinicians have better access to diagnostic tools.

"Lifestyle factors such as smoking, alcohol intake, stress, diet and exercise would also contribute."

Member for South West Coast Roma Britnell said the fact Warrnambool had worse healthcare outcomes in arthritis, asthma, heart disease and mental health showed just how important it was for the state government to ensure south-west residents had better access to services.

"It is concerning that the number of people with long-term health conditions such as heart disease in Warrnambool is higher than the state average," Ms Britnell said.

"The census clearly shows that there is a real need for the Victorian government to prioritise healthcare outcomes in regional areas like Warrnambool.

"Unfortunately, though, what has also become clearer and clearer over the past few months is that Victoria's healthcare system is in crisis across the board.

"As an example, in the South West Coast electorate, over the past few months we have seen a number of services cut at Portland District Health at a time when the community needs and deserves more services, not less.

"I have also raised concerns several times recently about my fear that upgrades to Warrnambool hospital will not be delivered on time.

"South West Healthcare has been under enormous pressure, especially in the emergency department, making the redevelopment of the hospital a priority to be delivered as soon as possible."

Affected by this story? There is help available:

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