Patients treated for cholesterol lowering appear to have extra benefits.
Diabetes patients who are being treated with statins as secondary prevention of coronary artery disease appear to have a lowered incidence of infections, which are generally higher in diabetes.
Because diabetes increases the risk for just about every disease by a five-fold greater risk of an infection, diabetes patients also had a 23% reduced risk when compared with the general population, and a rate that was similar for patients without diabetes taking statins when compared with the general population studied.
The rate of pneumonia infections requiring hospitalization in people without diabetes was about 1.54 per 1,000-person years compared with a rate of 6.02 per 1,000-person years among people with a diabetes diagnosis. And the rate of all bacterial infections requiring hospitalization was 2.08 per 1,000-person years in the general population compared with a rate of 9.13 per 1,000-person years among patients who had a diabetes diagnosis.
Statin therapy has a protective function against infections only when presumably used in secondary prevention either in patients with or without diabetes and with previous cardiovascular disease.
Dr. G. Seghieri, who ran the study, speculated that because statin therapy appears to play a greater role in patients who already have cardiovascular disease, it may have caused confounding in various papers that reported uneven outcomes associated with statins. His poster presentation noted that when the researchers drilled down further into the data they found that statin therapy was even more of a preventive among patients who were taking the stains as a preventive measure for cardiovascular disease. In those patients, taking statins reduced the risk of an infection requiring hospitalization by 31%, but the reduction in patients taking statins for reasons other than coronary artery disease was 7%.
The results showed that while statins may produce a benefit in preventing infections, the work is not definitive: While the retrospective data can produce compelling numbers, prospective trials are lacking. Presently it is widely accepted that statins confer cardiovascular benefit — primary and secondary — but statin use is not an accepted form of treatment or prevention of pneumonia. And while statins do not necessarily prevent infections, current guidelines do indicate that most people with diabetes over the age of 40 should be on statin therapy.
For the study, they accessed four administrative datasets, including a registry of all recipients of regional health care in Tuscany who were alive at the end of 2010 — a cohort of 3,663,415 individuals; the regional hospital administrative discharge list showing first discharges from hospitals with hospital codes indication infections — a total of 192,375 individuals; the dataset of the diabetic population registry; and those with baseline exposure to statin therapy based on a regional dataset of drug prescriptions.
During the 5-year period of the retrospective study, the researchers identified 30,597 people who were hospitalized for pneumonia, and 44,571 who were hospitalized for any bacterial infection, which could have included pneumonia cases.
They found that at baseline, 166,141 individuals who did not have a diagnosis of diabetes were prescribed statins. Of that group, 33,679 had been diagnosed with coronary artery disease; and 132,462 were being treated with statins for non-cardiac disease-related conditions. There were 64,181 patients who had been diagnosed with diabetes, and 15,271 were also diagnosed with cardiovascular disease; 48,897 did not have a diagnosis of coronary disease in addition to diabetes.
The higher risk of infection in patients with diabetes is confirmed by this observational study, showing that the 5-year risk of pneumonia and bacterial infections was about 50% greater than with people who did not have diabetes.
Having diabetes was associated with a 48% greater risk of being hospitalized for infections when compared with people who did not have such a diagnosis, and being a person with diabetes increased the risk of having any bacterial infection by about 64%.
So the question comes up, should all patients with diabetes be treated with a statin?
So besides reducing the risk for infections, it has been shown in different populations that a positive log-linear relation exists between blood LDL cholesterol and the risk of CHD, and this association persists well below the range of typical cholesterol levels.
A large body of data has provided the evidence that LDL lowering with statins, in a variety of populations at risk for CVD, including patients with diabetes, reduced the relative risk for cardiovascular events. However, it is important to emphasize that treatment decisions should be based not on the reduction in relative risk, but on the reduction of absolute risk.
Therefore, in patients with a high absolute cardiovascular risk, even a modest reduction in relative risk provides substantial clinical benefits. In addition, other parameters should also be considered, namely life expectancy, concomitant diseases, and quality of life.
- This large, retrospective study found higher rates of hospitalization for infection among people with diabetes compared with those without.
- Among people with diabetes, however, that rate was significantly reduced by statin use.
- This study was published as an abstract and presented at the EASD conference and conclusions should be considered to be preliminary until published in a peer-reviewed journal.
Source Reference: Seghieri G, et al “Effect of diabetes and of therapy with statins on the hospitalisation risk for infections: A population study” EASD 2016; Abstract 315.