ACCORD was a large (over 10,000 subjects, 71 centers) trial of lower A1c levels in people with advanced diabetes and pre-existing cardiovascular disease. Over 32% were already on insulin; their mean BMIs were over 30.

The intensive study group (goal A1c less than 6) had fewer nonfatal MIs. However, they had a greater overall death rate. Deaths occurred in cardiovascular categories as well as others. The intensive study group had far more people gaining over 10kg. In other words, the attempts at lowering A1c were made with medication, not lifestyle.

This has lead to a fear of lower A1c goals for everyone, and even using lifestyle. What it really meant was you shouldn't try lowering the A1c of advanced diabetics using meds alone.