Do statins raise the risk of diabetes?

Yes. Statins raise the chance of a new diabetes diagnosis a little, by about 10% at usual doses and more at high doses. The heart benefits are larger.

Who it's for

People with high heart risk gain most; those near the diabetes threshold face most of the added risk.

What to expect

About 1 extra diabetes case per 255 people treated for 4 years.

Watch out for

Higher doses carry more risk, mostly in people whose blood sugar is already borderline.

What guidelines say

The American Heart Association estimates statins add about 0.2% a year to the risk of newly diagnosed diabetes, depending on a group's underlying risk. For people whose statin is recommended by guidelines, it says the benefits greatly outweigh the risks6Guideline · 2019Statin Safety and Associated Adverse Events: A Scientific Statement From the American Heart Association.Restarting statin therapy in these patients can be challenging, but it is important, especially in patients at high risk of cardiovascular events, for whom prevention of these events is a priority. Overall, in patients for whom statin treatment is recommended by current guidelines, the benefits greatly outweigh the…Arterioscler Thromb Vasc Biol.

What the studies show

• A pooled analysis of individual data from 19 placeboplacebo A dummy treatment that looks like the real one, so people can't tell which they got.-controlled trials (123,940 people, median 4.3 years) found low or moderate-intensity statins linked to a 10% higher relative rate of new diabetes than a dummy pill (placebo): 1.3% vs 1.2% per year. High-intensity statins raised it 36% (4.8% vs 3.5% per year)1Meta-analysis · 2024 · 9,935 peopleEffects of statin therapy on diagnoses of new-onset diabetes and worsening glycaemia in large-scale randomised blinded statin trials: an individual participant data meta-analysis.Statins cause a moderate dose-dependent increase in new diagnoses of diabetes that is consistent with a small upwards shift in glycaemia, with the majority of new diagnoses of diabetes occurring in people with baseline glycaemic markers that are close to the diagnostic threshold for diabetes. Importantly, however, any…Lancet Diabetes Endocrinol.
• In that analysis, the size of the absolute gap depended mostly on how often blood sugar (HbA1c) was checked, not on the relative increase. Most new diagnoses were in people already close to the diabetes threshold1Meta-analysis · 2024 · 9,935 peopleEffects of statin therapy on diagnoses of new-onset diabetes and worsening glycaemia in large-scale randomised blinded statin trials: an individual participant data meta-analysis.Statins cause a moderate dose-dependent increase in new diagnoses of diabetes that is consistent with a small upwards shift in glycaemia, with the majority of new diagnoses of diabetes occurring in people with baseline glycaemic markers that are close to the diagnostic threshold for diabetes. Importantly, however, any…Lancet Diabetes Endocrinol. These figures compare groups, so one person's gain or loss depends on their starting risk.
• An earlier pooled analysis of 13 trials (91,140 people, mean 4 years) found a 9% higher risk. Treating 255 people for 4 years caused one extra case. The risk was highest in older participants2Meta-analysis · 2010 · 1,000 peopleStatins and risk of incident diabetes: a collaborative meta-analysis of randomised statin trials.Statin therapy is associated with a slightly increased risk of development of diabetes, but the risk is low both in absolute terms and when compared with the reduction in coronary events. Clinical practice in patients with moderate or high cardiovascular risk or existing cardiovascular disease should not change.Lancet.
• A pooled analysis of 5 trials (32,752 people, about 4.9 years) compared intensive with moderate doses. Intensive doses brought 12% higher odds of diabetes, or 2.0 extra cases per 1,000 patient-years. They also brought 6.5 fewer heart events per 1,000 patient-years3Meta-analysis · 2011 · 32,752 peopleRisk of incident diabetes with intensive-dose compared with moderate-dose statin therapy: a meta-analysis.In a pooled analysis of data from 5 statin trials, intensive-dose statin therapy was associated with an increased risk of new-onset diabetes compared with moderate-dose statin therapy.JAMA.
• Genetic data and trials agree. Statins added about 0.24 kg of body weight, and trial odds of diabetes were 12% higher, which suggests the effect comes from the drug's intended action5Meta-analysis · 2015 · 463 peopleHMG-coenzyme A reductase inhibition, type 2 diabetes, and bodyweight: evidence from genetic analysis and randomised trials.The increased risk of type 2 diabetes noted with statins is at least partially explained by HMGCR inhibition.Lancet.
• A review of 62 primary-prevention trials (120,456 people, 3.9 years) did not find a clear diabetes link. It did find small rises in muscle symptoms and liver problems4Meta-analysis · 2021 · 456 peopleAssociations between statins and adverse events in primary prevention of cardiovascular disease: systematic review with pairwise, network, and dose-response meta-analyses.For primary prevention of cardiovascular disease, the risk of adverse events attributable to statins was low and did not outweigh their efficacy in preventing cardiovascular disease, suggesting that the benefit-to-harm balance of statins is generally favourable. Evidence to support tailoring the type or dosage of…BMJ. Its result conflicts with the larger pooled analyses, which are stronger on this question.
• A study following postmenopausal women found a higher diabetes risk in statin users7Randomized trial · 2012 · 161,808 peopleStatin use and risk of diabetes mellitus in postmenopausal women in the Women's Health Initiative.Statin medication use in postmenopausal women is associated with an increased risk for DM. This may be a medication class effect. Further study by statin type and dose may reveal varying risk levels for new-onset DM in this population.Arch Intern Med. It was observationalobservational Studies that watch what happens to people rather than assigning a treatment. They can show links, not cause and effect., so it is weaker evidence.

Key studies

Safety

Blood sugar, weight, high blood pressure and triglycerides before treatment predicted who developed diabetes on atorvastatin8Randomized trial · 2011 · 3,798 peoplePredictors of new-onset diabetes in patients treated with atorvastatin: results from 3 large randomized clinical trials.High-dose atorvastatin treatment compared with placebo in the SPARCL trial is associated with a slightly increased risk of new-onset T2DM. Baseline fasting glucose level and features of the metabolic syndrome are predictive of new-onset T2DM across the 3 trials.J Am Coll Cardiol. Serious muscle injury occurs in under 0.1% of users and serious liver injury in about 0.001%6Guideline · 2019Statin Safety and Associated Adverse Events: A Scientific Statement From the American Heart Association.Restarting statin therapy in these patients can be challenging, but it is important, especially in patients at high risk of cardiovascular events, for whom prevention of these events is a priority. Overall, in patients for whom statin treatment is recommended by current guidelines, the benefits greatly outweigh the…Arterioscler Thromb Vasc Biol.

What we don't know

• Whether some statins carry more diabetes risk than others. Head-to-headHead-to-head A trial that compares two treatments directly with each other, rather than each with a placebo. results are inconclusive4Meta-analysis · 2021 · 456 peopleAssociations between statins and adverse events in primary prevention of cardiovascular disease: systematic review with pairwise, network, and dose-response meta-analyses.For primary prevention of cardiovascular disease, the risk of adverse events attributable to statins was low and did not outweigh their efficacy in preventing cardiovascular disease, suggesting that the benefit-to-harm balance of statins is generally favourable. Evidence to support tailoring the type or dosage of…BMJ,9Randomized trial · 2024 · 2,932 peopleEffect of rosuvastatin versus atorvastatin on new-onset diabetes mellitus in patients treated with high-intensity statin therapy for coronary artery disease: a post-hoc analysis from the LODESTAR randomized clinical trial.Among CAD patients receiving high-intensity statin therapy, the incidence of NODM was not significantly different between rosuvastatin and atorvastatin. However, a drug effect of the statin type on NODM was observed when the achieved LDL-C level was < 70 mg/dL.Cardiovasc Diabetol.
• How the small blood sugar rise occurs, beyond the drug's main action5Meta-analysis · 2015 · 463 peopleHMG-coenzyme A reductase inhibition, type 2 diabetes, and bodyweight: evidence from genetic analysis and randomised trials.The increased risk of type 2 diabetes noted with statins is at least partially explained by HMGCR inhibition.Lancet.