In Canada, money may matter for cancer survival
By Genevra Pittman
NEW YORK (Reuters Health) - Despite Canada's universal healthcare system, poorer Canadians with cancer are more likely to die early than their wealthier peers, suggests a new study of almost 100,000 patients from Ontario.
But unlike studies conducted in the United States, most of the difference in survival rates could not be explained by how early doctors caught the cancer.
"It is reassuring that stage of cancer (at diagnosis) does not vary across social groups in Ontario," Dr. Christopher Booth of the Queen's University Cancer Research Institute, the study's lead author, told Reuters Health in an email. But, he continued, "we need to better understand why survival does vary across socioeconomic groups."
The authors identified patients diagnosed with six different types of cancer in Ontario between 2003 and 2007. They used records of patients' home addresses to group the patients based on income levels in their communities. Then, the researchers calculated how likely patients in each group were to die of cancer in the three years after they were diagnosed or to die from any cause in the five years after.
They also looked at how early the cancer was caught for about 40,000 of those patients.
Poorer patients with cancer of the breast, colon, or larynx (voice box) were significantly more likely to die from cancer within three years than wealthier patients, while there was no significant difference for rectal, cervical, or nonsmall cell lung cancer.
For all cancers, wealthier patients had a better chance of being alive in five years than poorer patients. The biggest difference was in women with cervical cancer: 63 percent of the poorest group of patients survived for at least five years, compared to about 79 percent of the wealthiest group.
For the most part, differences in survival rates weren't a reflection of poorer patients getting diagnosed later, the authors report in the journal Cancer. On average, only poorer patients with breast and rectal cancer had more advanced disease when they were diagnosed compared with wealthier patients. And even these differences were only big enough to explain a "modest" fraction of the gap in survival rates at most, the authors say. Continued...