Effects of early use of pioglitazone in combination with metformin in patients with newly diagnosed type 2 diabetes.
BACKGROUND
Type 2 diabetes is characterised by a progressive decline in HbA1c control over time. Early combination therapy, rather than sequential introduction of individual oral glucose-lowering agents, has been proposed to prevent this gradual rise in HbA1c. This observational study assessed the effect of early dual combination oral glucose-lowering therapies within 6 months of diagnosis in newly diagnosed, drug-naïve patients with type 2 diabetes.


METHODS
This was an observational, open-label, non-randomised study in newly diagnosed patients with type 2 diabetes, aged 35-70 years, with HbA1c levels > 8.0% at diagnosis or > 7.0% at the 3-6-month follow-up. Patients were allocated to dietary management alone if the HbA1c level was 7.0-8.0% at diagnosis. Metformin combined with gliclazide, repaglinide, or pioglitazone was given at diagnosis if the HbA1c was > 8.0%. Similar treatments were introduced at 3-6 months if the HbA1c was > 7.0%. Over a 3-year period, HbA1c was measured at 3-monthly intervals. All patients underwent regular dietetic review. Target HbA1c was < or = 7.0%.


RESULTS
416 patients were considered eligible for inclusion, with a mean (+/- SD) age of 54.1 +/- 9.2 years, BMI of 33.5 +/- 6.1 kg/m2, and baseline HbA1c of 8.6 +/- 1.7%. A mixed model analysis of variance on the 178 patients who started with combination therapy, either immediately or after a 3-6 month period on diet, showed that metformin plus gliclazide, repaglinide, or pioglitazone was associated with a gradual increase in HbA1c values. Amongst those patients treated with the metformin/pioglitazone combination there was an estimated 0.1% increase in HbA1c/year. This was much less pronounced than the rises seen in HbA1c/year of 0.5% with the metformin/gliclazide and metformin/repaglinide combinations.


CONCLUSIONS
This preliminary analysis of an observational, non-randomised, open-label ongoing study has shown that early use of combination therapy at time of diagnosis or within the first 3-6 months following diagnosis with metformin plus pioglitazone in newly diagnosed type 2 diabetes results in a slower deterioration in glycaemic control than that with metformin combined with either gliclazide or repaglinide. This may be due to the beta-cell protective properties of pioglitazone. These results need to be confirmed by further studies with a more robust design and methodology.
Chalmers
J
J
Diabetes Centre, Victoria Hospital, Kirkcaldy, Fife, UK. john.chalmers@faht.scot.nhs.uk
Hunter
J E
JE
Robertson
S J
SJ
Baird
J
J
Martin
M
M
Franks
C I
CI
Whately-Smith
C R
CR
Mariz
S
S
Campbell
I W
IW
D000328:Adult; D001786:Blood Glucose / Q000032:analysis; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy*; D004359:Drug Therapy, Combination; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007004:Hypoglycemic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D008297:Male; D008687:Metformin / Q000008:administration & dosage / Q000627:therapeutic use*; D008875:Middle Aged; D000077205:Pioglitazone; D045162:Thiazolidinediones / Q000008:administration & dosage / Q000627:therapeutic use*; D016896:Treatment Outcome
D001786:Blood Glucose; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D008687:Metformin; D000077205:Pioglitazone; D045162:Thiazolidinediones