Statins are commonly prescribed for preventing cardiovascular diseases, such as heart attack and stroke. Now, a pooled analysis of published studies covering millions of participants finds that the cholesterol-lowering drugs may also prevent venous thromboembolism, a leading but avoidable cause of hospital deaths.
Researchers from the University of Leicester and the University of Bristol, both in the United Kingdom, report their findings in The Lancet Haematology.
They suggest that once other studies confirm their findings, they could lead to new guidelines for statin use to cover the prevention of vein blood clots, as well as cardiovascular disease.
Venous thromboembolism (VTE) is a life-threatening condition in which blood clots form in the vein.
VTE is a leading cause of death and disability. Estimates suggest that around 10 million cases occur worldwide every year, and it is one of the most preventable causes of hospital-related deaths.
Statins are drugs that can help to lower blood levels of low-density lipoprotein (LDL) cholesterol by reducing its production in the liver.
'Great promise beyond lipid-lowering effect'
Lead author Dr. Setor Kunutsor, of the School of Clinical Sciences at the University of Bristol, says that while statins are currently only approved for use in the primary and secondary prevention of cardiovascular disease, they have also shown "great promise beyond their established lipid-lowering effects and these include potential beneficial impact on multiple disease conditions."
- Estimates suggest that there are between 100,000-300,000 VTE-related deaths in the United States every year
- In the U.S. and Europe, deaths linked to VTE exceed those of breast cancer, prostate cancer, AIDS, and road crashes combined
- Up to 60 percent of VTE cases happen during or after hospital stays.
In their study background, Dr. Kunutsor and colleagues note that there have been suggestions that statins may prevent VTE, but "the evidence is uncertain."
To evaluate the extent to which statins have been linked with first VTE events, the researchers undertook a systematic review and meta-analysis of observational studies and randomized controlled trials. A meta-analysis is a study that pools and analyzes data from several studies of similar or compatible design.
They searched several well-known databases for studies up to July 2016 that reported links between statin use and first VTE outcomes.
The observational studies (investigations that follow people over a period of time) included in the analysis assessed the link between statin use and VTE, DVT, or PE in adults.
The randomized controlled trials included in the analysis had compared the effect of statin therapy against receiving no treatment or placebo use, and they had collected data on VTE, DVT, and PE outcomes.
Statins reduced VTE threat by 15-25 percent
Altogether, the researchers analyzed 36 studies with data on more than 3.2 million participants. They took into account age, country of origin, and whether there was a high or low risk of developing VTE.
The analysis showed that, compared with not using statins, there was a clear link between statin use and a reduced risk of VTE.
Results showed a 15-25 percent reduction in relative risk for VTE in those who used statins versus those who did not.
The authors note that due to limited data, they could not clearly show whether all types of statin were equally effective.
They also point out that further evidence must validate the findings before guidelines for statin use are expanded to include prevention of VTE, as well as cardiovascular disease.
"These results provide an extensive body of evidence on the clinical benefit of statin in the occurrence of VTE and may support a true protective effect."
Dr. Setor Kunutsor