Yes, but it’s more useful to think of it the other way round, as something to gain rather than something to blame. Keep your blood sugar level under good control. This helps you heal faster and helps your body fight infections.
That holds across several wound types. With venous ulcers and with ischemic ulcers alike: if you have diabetes, keep your blood sugar level under control. This will help you heal faster.
Diabetes itself is one of the factors that can prevent wounds from healing or slow the process. People with diabetes are more likely to have wounds that will not heal, also called long-term or chronic wounds. Diabetes is at the top of the list of reasons certain wounds may not heal well.
This page doesn’t give a blood sugar target. If you have been given targets, those came from the people managing your diabetes, and they are the ones to ask about what yours should be.
It is also one factor among many, which is worth knowing before carrying the whole weight of a slow wound. Other factors include infection, poor blood flow, obesity, age, heavy alcohol use, stress, certain medicines, and smoking. Wounds that are slow to heal usually have more than one reason behind them, and working out which apply is one of the jobs of a wound care team.
So the practical question is not whether blood sugar matters — it does — but whether the people treating the wound and the people treating the diabetes are talking to each other. Diabetes care is one of the kinds of help a wound care center may provide alongside the wound treatment itself.