However, in older people, the health benefits of lowering HbA1c levels to below 7.5% are uncertain. This is especially true for people with several medical problems. Worse, low blood sugar levels can cause harm in some people. Aiming for HbA1c levels below 7.5% increases the risk for hypoglycemia (low blood sugar). Severe low blood sugar can result in confusion, coma, falls, fractures, abnormal heart rhythms, and even death.