A diabetic woman uses a makeshift tourniquet to help draw blood to test her sugar level. (Tom Strickland/Associated Press)

People with diabetes in Ontario are dying prematurely less frequently, but the decline in mortality rate was smaller among those who earn less, researchers say.

The study's authors found the death rate for diabetics fell by 33 per cent across the province between 1995 and 2006, after taking age and sex into account. But the group also found that a person's chances of survival with the disease improved as income increased.

"The death rate didn't go down as much in lower-income populations as it did in higher-income populations, suggesting that our lower-income populations may be lagging behind in terms of improvement of diabetes care," said Dr. Lorraine Lipscombe of Women's College Hospital in Toronto.

People living in higher-income neighbourhoods experienced a larger decline in mortality, 36 per cent, than that among people in the lowest-income group, which was 31 per cent, the team reported in Monday's issue of the Canadian Medical Association Journal.

Worldwide, diabetes, mainly Type 2, is associated with a doubling in premature mortality, with most deaths occurring because of cardiovascular issues. Survival for people with diabetes has improved over the last 10 years, partly thanks to better diabetes care and fewer heart attacks and strokes.

The researchers said differences in care by income may include:

• Seeing a doctor on a regular basis.
• Screening for diabetes, since those who are screened and treated earlier may fare better.

The findings suggest that the cost of managing diabetes is a burden for those who make less money and don't have benefits, Lipscombe said. She called the cost of medications and supplies a "significant barrier" to effective care for patients who cannot afford them.

Costs of drug, supplies

Income had a much smaller effect on mortality trends among people over the age of 65. In Ontario, medication costs and supplies are covered for people over the age of 65, and the income-related difference in mortality for this group rose by only 0.9 per cent over the study period, the team found.

Among those aged 30-64, the gap in the mortality ratio between the highest and lowest income groups widened by more than 40 per cent.

The cost of the drugs and supplies seems to be an issue for those under the age of 65 in the province, the team from the Institute for Clinical Evaluative Sciences in Toronto said.

People with diabetes who come to the Scarborough Community Diabetes Program for help, for example, often must make tough decisions about paying for insulin, medicine and test strips that some must use up to five times a day at a cost of $1 each, said Parnaz Sidighi, co-ordinator of the program.

Some patients also have an added cost when high blood glucose causes tooth and gum problems.

"They didn't have money to go and buy some dentures," Sidighi said. "[One patient] was just 30 kilos. Just imagine how fragile this person can be, and then struggling with purchasing the medication, and strips and foods and her dentures."

Changing demographics, particularly due to immigration, may also play a role. Between 1996 and 2006, 37 per cent of immigrants were South Asian, a group susceptible to diabetes and cardiovascular complications. And new immigrants often have lower incomes than more established residents.

"Our study highlights the urgent need to address barriers to adequate diabetes care in low-income populations, to stem the rising burden of diabetes among poorer people," the study's authors concluded.

With files from The Canadian Press