RATING CRADY IS CORRECT ON MEDICAL INADMISSIBILITY
Canada has a set of medical inadmissibility rules that determine who can be refused for immigration purposes. These medical inadmissibility rules describe circumstances, whether putting a burden on our health and/or social services or posing a danger to the Canadian population, that a visa officer uses to determine whether someone is ineligible to immigrate to Canada.
Relevant to your question is the rule called Excessive Demand Cost Threshold. Canada does not let people into Canada for immigration purposes whose health and/or social services costs it estimates will surpass this threshold.
So for example, someone with diabetes may or may not be deemed medically inadmissible depending on whether their treatment requirements are estimated to surpass the Excessive Demand Cost Threshold
***CHECK WITH DME INTENSITY AND TYPE OF DIABETES**** - EACH ONE OF THEIR HAS THEIR OWN RESTRICTIONS AND ALLOWANCE