Statins raise the risks for increased glucose levels and the development of type 2 diabetes among people who don’t have it at baseline, but those risks are outweighed by the cardiovascular benefit, new data suggested.
The findings come from an analysis of individual participant data from a total of 23 randomized trials of statin therapy involving 154,664 individuals. In people without diabetes at baseline, statin therapy produces a dose-dependent increase in the risk for diabetes diagnosis, particularly among those whose glycemia marker levels are already at the diagnostic threshold.
Statins also tend to raise glucose levels in people who already have diabetes, but “the diabetes-related risks arising from the small changes in glycemia resulting from statin therapy are greatly outweighed by the benefits of statins on major vascular events when the direct clinical consequences of these outcomes are taken into consideration,” wrote the authors of the Cholesterol Treatment Trialists’ (CTT) Collaboration in their paper, published online in The Lancet Diabetes & Endocrinology.
Moreover, they say, “since the effect of statin therapy on measures of glycemia within an individual is small, there is likely to be little clinical benefit in measuring glucose concentrations and A1c values routinely after starting statin therapy with the aim of making comparisons to values taken before the initiation of a statin. However, people should continue to be screened for diabetes and associated risk factors and have their glycemic control monitored in accordance with current clinical guidelines.”
The CTT is co-led by Christina Reith, MBChB, PhD, and David Preiss, PhD, FRCPath, MRCP, both of the Nuffield Department of Population Health, University of Oxford, England.
In an accompanying editorial,
Dr. Gerstein and Dr. Pigeyre also said “these findings emphasize the importance of holistic care. As people at risk for cardiovascular outcomes are also at risk for type 2 diabetes, any prescription of a statin should be accompanied by promoting proven strategies to prevent or delay diabetes, such as modest weight reduction and increased physical activity. Finally, these findings emphasize the importance of always being alert for harmful adverse effects, even with the most beneficial and successful preventive therapies.”
Statins Raise Diabetes Risk, Glucose Levels Slightly
The meta-analysis of trials in the CTT Collaboration included individual participant data from 19 double-blind randomized, controlled trials with a median follow-up of 4.3 years comparing statins with placebo in a total of 123,940 participants, including 18% who had known type 2 diabetes at randomization. Also analyzed were another four double-blind trials of lower- vs higher-intensity statins involving a total of 30,724 participants followed for a median of 4.9 years, with 15% having diabetes at baseline.
In the 19 trials of low- or moderate-intensity statins vs placebo, statins resulted in a significant 10% increase in new-onset diabetes compared with placebo (rate ratio, 1.10), while high-intensity statins raised the risk by an also significant 36% (1.36). This translated to a mean absolute excess of 0.12% per year of treatment.
Compared with less intensive statin therapy, more intensive statin therapy resulted in a significant 10% proportional increase in new-onset diabetes (1.10), giving an absolute annual excess of 0.22%.
In the statin vs placebo trials, differences in A1c values from placebo were 0.06 percentage points higher for low- or moderate-intensity statins and 0.08 points greater for high-intensity statins.
Nearly two thirds (62%) of the excess cases of new-onset diabetes occurred among participants in the highest quarter of the baseline glycemia distribution for both low-intensity or moderate-intensity and high-intensity statin therapy.
And among participants who already had diabetes at baseline, there was a significant 10% relative increase in worsening glycemia (defined by adverse glycemic event, A1c increase of ≥ 0.5 percentage points, or medication escalation) with low- or moderate-intensity statins compared with placebo and a 24% relative increase in the high-intensity trials.
The Nuffield Department of Population Health has an explicit policy of not accepting any personal honoraria payments directly or indirectly from the pharmaceutical and food industries. It seeks reimbursement to the University of Oxford for the costs of travel and accommodation to participate in scientific meetings. Dr. Reith reported receiving funding to the University of Oxford from the UK National Institute for Health and Care Research Health Technology Assessment Programme and holding unpaid roles on the Clinical Data Interchange Standards Consortium as a board member and WHO as a scientific advisor. Dr. Preiss reported receiving funding to his research institution (but no personal funding) from Novartis for the ORION 4 trial of inclisiran, Novo Nordisk for the ASCEND PLUS trial of semaglutide, and Boehringer Ingelheim and Eli Lilly for the EMPA-KIDNEY trial and being a committee member for a National Institute for Health and Care Excellence guideline.
Dr. Gerstein holds the McMaster-Sanofi Population Health Institute Chair in Diabetes Research and Care. He reported research grants from Eli Lilly, AstraZeneca, Novo Nordisk, Hanmi, and Merck; continuing medical education grants to McMaster University from Eli Lilly, Abbott, Sanofi, Novo Nordisk, and Boehringer Ingelheim; honoraria for speaking from AstraZeneca, Eli Lilly, Novo Nordisk, DKSH, Zuellig Pharma, Sanofi, and Jiangsu Hanson; and consulting fees from Abbott, Eli Lilly, Novo Nordisk, Pfizer, Carbon Brand, Sanofi, Kowa, and Hanmi. Pigeyre had no disclosures.
A version of this article appeared on Medscape.com.