Hamilton area emergency rooms are being flooded with more patients than anywhere else in the province, according to a new study from Health Quality Ontario.

The study, which comes as local hospitals are warning of a strain felt under an influx of patients, also shows that the Hamilton LHIN (which includes Niagara, Haldimand and Brant) has the highest number of patients admitted from emergency rooms into hospital.

On top of that, the Hamilton LHIN also has the highest number of patients coming in with "high acuity" problems, meaning that the area is seeing the most people coming in with serious problems.

'You really only get admitted if you're pretty sick.' - Dr. Joshua Tepper, president and CEO of Health Quality Ontario

"It clearly suggests that your emergency departments are working very hard," said Dr. Joshua Tepper, the president and CEO of Health Quality Ontario.

The local LHIN is also dealing with a "fair amount of illness burden," he said.

(LHIN stands for Local Health Integration Network. In each region of the province, the local LHIN is the authority responsible for regional administration of public healthcare services.)

Hospitals showing signs of stress

The report shows that the local LHIN saw 670,444 emergency room visits in 2014/2015, which is over 100,000 more visits than the nearest comparable area.

Just under 72,000 people were admitted from the emergency room to hospital, which is the most in the province.

The report also says that 378,116 of the patients seen in area hospitals during that timeframe were high needs patients, which is again, the most in the province.

"Many of them are quite sick. They are quite unwell," Tepper said. "And you really only get admitted if you're pretty sick."

All of this comes as Hamilton's hospitals are showing increasing signs of stress. According to an internal memo sent by Hamilton Health Sciences CEO Rob MacIsaac to staff and doctors, hospitals have been dealing with "significant care pressures" since mid October.

The organization says its doctors have been regularly operating at over 100 per cent capacity to keep up with demand.

St. Joseph's Healthcare Hamilton has been dealing with similar issues since August, said Anne Marie MacDonald, director of surgery. Where on average they would be seeing 160 patients a day in the emergency department, now they are seeing about 180.

What is causing this rise?

MacIsaac attributed the recent surge to an early onset of the flu, but Tepper told CBC News that it's difficult to say exactly what has caused the numbers to shoot up over a longer period of time.

"Is it cardiac related or poverty related? Do you have an older, sicker population?"

Most recent census data says that one in five Hamiltonians are under the poverty line, while closer to one in four children and youth are living in poverty.

Statistics Canada data says about 16 per cent of Hamilton's population is made up of seniors aged 65 or older, which is higher than the 14.8 per cent of the national population. 

A new report from the Institute for Clinical Evaluative Sciences also shows that the Hamilton LHIN had the highest number of opioid-related hospital admissions and emergency department visits in the entire province in 2014.

adam.carter@cbc.ca