Statins for primary prevention: do benefits outweigh DM risk?

Takeaway

• Statin use was associated with significantly increased time- and dose-dependent risk of new-onset diabetes mellitus (DM).
• Data suggest caution in use of high-dose statins for long-term primary prevention.  

Why this matters

• Indications for statin use in primary and secondary prevention have been expanding, but safety regarding increased DM risk is controversial.

Study design

• From national health insurance data, comparison of 638,625 statin users with 1,523,494 never-users, all aged ≥40 years with hypercholesterolemia.
• Propensity-score matching identified 518,491 matched pairs of statin users and nonusers with similar baseline characteristics.
• Funding: National Evidence-based Healthcare Collaborating Agency, Seoul, Korea.

Key results

• In average 3.9-year follow-up, new-onset DM occurred in 13.4 vs 6.9/1000 person-years among statin users and nonusers, respectively (adjusted HR [aHR], 1.88; 95% CI, 1.85-1.93).
• DM risk increased by statin use duration, with aHR, 2.62 (2.56-2.67) for >2 years vs 1.25 (1.21-1.28) for <1 year.  
• By statin intensity, aHR was 2.31 (2.26-2.37) for high vs 1.75 (1.71-1.78) for low.  
• By cumulative dose, aHR was 2.52 (2.47-2.57) for third tertile vs 1.06 (1.02-1.10) for first tertile.

Limitations

• Record-based data.  
• Nonrandomized, observational.
• No data on high-density lipoprotein cholesterol, triglycerides.
• Possible survivor bias.
• Single country.