Statins beneficial as primary CVD prevention in older adults, study suggests

Key takeaways:

• Statin therapy was tied to a 5-year CVD risk reduction in adults aged 75 years and older.
• Statin use did not increase the risk for major adverse events, such as liver dysfunction.

Statins were associated with a reduced risk for CVD and death in older adults, even those aged 85 years and older, data in Annals of Internal Medicine showed.

Researchers said the findings support the use of statin therapy as primary CVD prevention in this population.

In August, the U.S. Preventive Services Task Force said there is insufficient evidence to assess the benefits and harms of starting statin therapy in adults aged 76 years and older for primary prevention of CVD and mortality.

Previous studies on the potential benefits of statin therapy are limited by an underrepresentation of older populations, Wanchun Xu, MPhil, a PhD student in the department of family medicine and primary care at the University of Hong Kong in China, and colleagues noted.

“Therefore, it is crucial to understand the potential benefits and risks of statin therapy in old and very old adults to make informed decisions regarding statin treatment,” they wrote.

The researchers conducted a target trial emulation study using electronic health record data of adults aged 60 years and older who met indications for statin treatment but had no prior CVD diagnosis from January 2008 to December 2015.

Xu and colleagues compared the risk for CVD — such as myocardial infarction, stroke or heart failure — as well as mortality and major adverse events between statin initiators vs. noninitiators (intention-to-treat analysis) and continuous statin users vs. those who never used statins (per protocol analysis).

Overall, 97,462 participants who initiated statin therapy were matched to 97,462 participants who did not initiate therapy.

Among 42,680 matched participants aged 75 to 84 years and 5,390 matched participants aged 85 years or older, 9,676 and 1,600 of them developed CVDs over an average follow-up of 5.3 years, respectively.

The researchers reported that, among adults aged 75 to 84 years, the 5-year standardized risk reduction for overall CVD incidence associated with statin therapy was:

• 1.2% (95% CI, 0.57%-1.82%) in the intention-to-treat analysis; and
• 5% (95% CI, 1.11%-8.89%) in the per protocol analysis.

Meanwhile, among adults aged 85 years and older, the 5-year standardized risk reduction for overall CVD incidence associated with statin therapy was:

• 4.44% (95% CI, 1.4%-7.48%) in the intention-to-treat analysis; and
• 12.5% (95% CI, 4.33%-20.66%) in the per protocol analysis.

Additionally, statin use in adults aged 75 years and older did not increase the risk for myopathies and liver dysfunction, and the observed risk reductions were not limited to those with coronary heart disease risk equivalents like diabetes.

The researchers noted that the results may have been impacted by unmeasured confounders such as lifestyle factors, including diet and physical activity, as well as shared decision-making between patients and physicians.

Additionally, “we acknowledge the possibility of inherent information bias when using EHRs to define the variables in the analysis,” they wrote.

Future research using randomized controlled trials are warranted “to verify the findings from the observational studies and inform clinical decisions,” Xu and colleagues added.

Still, “our study results support the prescription of statin therapy for primary prevention of CVD in old and very old adults,” they concluded.