It does look like diabetes mellitus is a rather complicated disease. We know that we need to control the sugar level, to reduce the risk of complications. Yet we also know that you can also increase mortality with too intensive a control. Too high is bad and too low is bad too. Although there is much evidence on this J-curve phenomena, some still do not believe in it and demand more evidence.
Well, the plot thickens with the 25th march, American Journal of Cardiology article on management of T2DM in patients with heart Failure. Dr Tamara Horwich and colleagues at UCLA did a retrospective cohort analysis of 845 patients with heart failure. 358 of them were diabetic, and 487 were non diabetic. Some of them with CCF were so bad and were awaiting cardiac transplantation. After 2 year of follow-up, he found that amongst the diabetics, fair control ( HBA1c of 7.2-8.2% ) was associated with better survival then those whose HBA1c control was less than 7.2%.
Patients with diabetes: Two-year survival free from death/urgent heart transplantation
| Quartile || HbA1C (%) || 2-y survival (%) |
| 1 || <6.4 || 47.9 |
| 2 || 6.5-7.2 || 41.5 |
| 3 || 7.3-8.5 || 60.7 |
| 4 || >8.6 ||65.3|
However, one must note that this is a retrospective, observational cohort study, and by no means conclusive. We will have to ( as usual ) await larger controlled trials to prove the point.
I was impress that we now again have more evidence of a J-curve phenomena in the control of diabetes, in patients with severe heart failure.
Interesting. Looks like too much of a good thing, is a bad thing, in some situations.