The incidence of delirium in patients pretreated with statins who remain in an intensive care unit after cardiac surgery

LETTER TO THE EDITOR

Clínica Cardiológica Giffhorn - Curitiba (PR), Brazil

Corresponding author

"Something is impossible only until someone doubts and proves the opposite".

Albert Einstein

Dear Editor,

I read, with great interest, the article "The incidence of delirium in patients pretreated with statins who remain in an intensive care unit after cardiac surgery," published by Cruz et al. in the Brazilian Journal of Intensive Therapy (Revista Brasileira de Terapia Intensiva) volume 24, number 1, pages 52 to 57.⁽¹⁾ The subject is highly relevant.

In 1970, Akira Endo synthesized inhibitors of hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase (statins) from fungal metabolites that inhibit cholesterol synthesis to counteract parasites. The compound was called compactin.

In animal models (except rats), the new inhibitors were effective in diminishing total cholesterol by approximately 30%. After the reduction of medication levels due to the occurrence of lymphomas and with the development of lovastatin, broader use in humans was able to begin in 1987.^(2,3)

Statins have demonstrated powerful effects on the overall reduction of cholesterol (by the inhibition of hepatic cholesterol synthesis) and on the subsequent increase in the number of hepatic LDL receptors. Hypercholesterolemia causes endothelial dysfunction, and the statins can even result in the removal cholesterol from arterial walls.⁽⁴⁾

Pleiotropic effects are so named because they encompass effects unrelated to those involving LDL production as a result of therapy with statins and are perhaps related to actions in the vascular wall.

Among the pleiotropic effects, we can list effects on sepsis, deep vein thrombosis, endometriosis, and chronic obstructive pulmonary disease (COPD) as well as neuroprotective effects. These effects have not yet been fully explained but remain much discussed. In addition, included here are studies related to delirium in the immediate postoperative (IPO) period after cardiac surgery.

I would like to ask the author about the patients who used alcohol or psychiatric drugs or who were elderly (over 65 years) during the preoperative period. Was there a greater presence of delirium in the IPO period? Mariscalco et al. observed that these groups presented greater risks.⁽⁵⁾ The other question would be regarding the patients who underwent aneurysm correction or aortic dissection: do they present a greater number of delirium cases?

In light of today's knowledge and despite the anti-inflammatory, immunomodulator, and antithrombotic effects of statins, the "Holy Grail" (the statins) has not yet been discovered or unveiled. Additionally, because "happiness, health, and eternal youth" are facing the collateral effects to be considered in treatment.⁽⁶⁾

Sincerely,

Hélcio Giffhorn

REFERENCES

• 1. Cruz JN, Tomasi CD, Alves SC, Macedo RC, Giombelli V, Cruz JG, et al. Incidência de delirium durante a internação em unidade de terapia intensiva em pacientes pré-tratados com estatinas no pós-operatório de cirurgia cardíaca. Rev Bras Ter Intensiva. 2012;24(1):52-7.
• 2. Lyons KS, Harbinson M. Statins: in the beginning. J R Coll Physicians Edinb. 2009;39(4):362-4.
• 3. Fonseca FAH. A guerra do colesterol. In: A história dos lípides. São Paulo: Planmark Editora; 2011.
• 4. Adam O, Laufs U. Antioxidative effects of statins. Arch Toxicol. 2008;82(12):885-92.
• 5. Mariscalco G, Cottini M, Zanobini M, Salis S, Dominici C, Banach M, et al. Preoperative statin therapy is not associated with a decrease in the incidence of delirium after cardiac operations. Ann Thorac Surg. 2012;93(5):1439-47.
• 6. Jeger R, Dieterle T. Statins: have we found the Holy Grail? Swiss Med Wkly. 2012;142:w13515. Review.

The incidence of delirium in patients pretreated with statins who remain in an intensive care unit after cardiac surgery

Hélcio Giffhorn

Publication Dates

• Publication in this collection
  05 Nov 2012
• Date of issue
  Sept 2012