Type 2 diabetes: safety and efficacy of pioglitazone monotherapy

Takeaway

• This meta-analysis supports pioglitazone as an effective treatment option for the management of type 2 diabetes mellitus (T2DM) because of its potential to lower hyperglycaemia, adverse lipid metabolism and blood pressure (BP).

Why this matters

• Pioglitazone, the only thiazolidinedione drug in clinical practice, is under scrutiny because of reported adverse effects, but its unique insulin sensitising action provides rationale to remain as a therapeutic option for T2DM management.

Study design

• 16 studies involving 2681 patients with T2DM met eligibility criteria after a search across electronic databases.
• Efficacy outcomes: mean changes in glycated haemoglobin (HbA1c) level, fasting blood sugar (FBS) level, body weight (BW) and homeostasis model assessment-insulin resistance (HOMA-IR).
• Safety outcomes: changes in BP, lipid parameters and incidences of adverse events.
• Funding: None.

Key results

• Both pioglitazone and comparative monotherapies were equally effective in reducing:
  • HbA1c level (mean difference [MD], 0.05%; P=.56; I², 81%);
  • HOMA-IR (weighted mean difference [WMD], 0.05; P=.86);
  • BP (WMD, −1.05 mmHg; P=.52); and
  • triglycerides level (WMD, −0.71 mmol/L; P=.16).
• Pioglitazone monotherapy significantly reduced FBS level (MD, 0.24 mmol/L; P=.04; I², 65%) and increased BW (WMD, 2.06 kg; P<.0001) vs comparative monotherapies.
• Pioglitazone monotherapy was equally effective as comparative monotherapies in increasing high-density lipoprotein level (WMD, 0.02 mmol/L; 95% CI, −0.06 to 0.10).
• Pioglitazone monotherapy was significantly associated with increased risk for oedema (risk ratio [RR], 2.21; P=.0001) and decreased risk for hypoglycaemia incidence (RR, 0.51; P=.003).

Limitations

• Heterogeneity among studies.
• Small sample size.