Key Takeaway:
- Early statin use was linked to a 15% lower 10-year dementia risk in people with newly diagnosed type 2 diabetes.
- Later statin use was linked to a 10% lower risk compared with no statin treatment.
- The study shows an association, not causation, so further research is needed to confirm whether statins directly reduce dementia risk.
Starting statins soon after a type 2 diabetes diagnosis is associated with a modestly lower dementia risk, according to a large Danish study published in The Lancet Regional Health, underscoring the Statins dementia risk link.
Early statin use shows greater benefit
Researchers analysed national health-register data from 132,585 people diagnosed with type 2 diabetes between 2006 and 2019 who had never taken statins before their diagnosis.
Patients who began statin treatment within a year of their diabetes diagnosis had a 15% lower relative risk of dementia after 10 years than those who did not receive statins. Those who began treatment one to five years after diagnosis had a 10% lower relative risk.
The estimated 10-year absolute risk of dementia was 3.3% among people who started statins early, 3.5% among those who started treatment later and 3.9% among those who did not receive statins.
“In individuals developing type 2 diabetes, statins were associated with a lower risk of dementia, most pronounced in those with early initiation,” said Tummas Ternhamar, a medical doctor at Copenhagen University Hospital who led the research.
“Statins seem to be underused in patients with type 2 diabetes, despite their protective effects against cardiovascular disease,” Ternhamar said.
Study finds association, not cause
Statins are commonly prescribed to lower low-density lipoprotein cholesterol, or LDL-C, which can contribute to cardiovascular disease when levels are too high. People with type 2 diabetes face an increased risk of cardiovascular disease and may also have elevated LDL-C.
The 2024 Lancet Commission on dementia identified high LDL-C as a modifiable risk factor for dementia. Researchers examined whether treating cholesterol soon after a diabetes diagnosis might also be associated with better dementia outcomes.
However, the study is observational, meaning it identifies patterns in health data but cannot establish that statins directly prevent dementia, only an observed Statins dementia risk association. Other differences between people who received treatment and those who did not could have contributed to the results.
The findings therefore do not prove that statins cause a lower dementia risk, and further research is needed to determine whether the drugs have a direct protective effect against dementia.
Researchers urge timely cholesterol treatment
Isabel Goncalves, a cardiovascular disease researcher with the European Society of Cardiology who was not involved in the study, said the findings add to existing reasons for timely cholesterol treatment among people with type 2 diabetes.
“People with type 2 diabetes already have a higher risk of dementia and are advised to lower cholesterol to reduce their risk of heart attack and stroke,” Goncalves said.
“This study suggests that starting statins soon after a type 2 diabetes diagnosis may also be linked to a modest reduction in dementia risk, with greater benefit than delaying treatment,” she said.
Goncalves added that the findings could be important because statins are widely available and inexpensive.
Ternhamar said the results provide another potential reason to ensure that people with type 2 diabetes and high LDL-C receive timely statin treatment.
The study does not establish statins as a dementia treatment or prevention strategy, and the broader Statins dementia risk picture remains under investigation. Decisions about cholesterol-lowering therapy should be based on an individual’s medical circumstances and made with a health care professional.
