The relationship of glycaemic control and triglycerides in patients with diabetes mellitus: a PreCIS Database Study.

AIMS: A common therapeutic approach in patients with type 2 diabetes mellitus who have elevated triglycerides (TGs) is to treat the hyperglycaemia before specifically targeting high TG. The aims of the current study were (i) to determine whether there was a relationship between glycated haemoglobin (HgbA1c) and TG levels at the baseline visit and (ii) to analyse the relationship between DeltaHgbA1c and DeltaTG after treatment.

METHODS: Among 650 consecutive diabetic patients seen in the Cleveland Clinic Preventive Cardiology Department, 372 had both baseline and post-treatment HgbA1c and TG values. We analysed the relationship between baseline HgbA1c and TG as well as between the change in HgbA1c and the change in TG. For analysis, patients were divided into nine groups by tertiles of HgbA1c (< or =6.6, 6.7-7.8 and >7.8%) and TG (< or =1.75, 1.76-3.89 and >3.89 mmol/l) at baseline.

RESULTS: At baseline, there was a small correlation between HgbA1c and TG (r(2) = 0.051; p < 0.001). For the entire group, there was a significant correlation between DeltaHgbA1c and DeltaTG from baseline to follow-up (r(2) = 0.077; p < 0.001). Analyses by tertiles showed that DeltaTG were only associated with changes in two groups: HgbA1c tertile 3 (>7.8%) and TG tertiles 2 (r(2) = 0.24; p < 0.0001) and 3 (r(2) = 0.187; p = 0.003). For every 1% change in the top tertile HgbA1c, there was a 9.3% change in TG (tertile 2) and a 9.8% change in TG (tertile 3).

CONCLUSIONS: These observations suggest that for patients with diabetes mellitus and elevated TG, the effect of HgbA1c reduction has limited effects on TG reduction. Patients may benefit from TG-specific therapy initiated earlier rather than waiting to see effects of glycaemic control.