Hoge triglyceridespiegels geassocieerd met ischemische beroerte

Verhoogde niet-nuchtere triglyceridenspiegels zijn geassocieerd met een toegenomen kans op ischemische stroke (beroerte). Deze data zijn gepubliceerd in de Annals of Neurology, en afkomstig uit een analyse van de gegevens uit de Copenhagen City Heart Study. In deze studie zijn mannen en vrouwen betrokken waarvan de cholesterol- en triglyceridenspiegels vanaf 1976 bekend waren. Op dat moment gebruikten geen van de deelnemers aan het onderzoek cholesterolverlagende therapie.

Van de 7.579 vrouwen en 6.372 mannen kregen 837 mannen en 837 vrouwen een ischemische stroke gedurende een mediane follow-up duur van 26 jaar. Een associatie tussen verhoogd cholesterol en ischemische beroerte werd niet gezien in deze studie, behalve bij mannen met de hoogste cholesterolniveaus.

Huidige richtlijnen doen aanbevelingen over de optimale cholesterolniveaus voor de bescherming tegen ischemische beroertes maar niet over de optimale triglyceridenspiegels, hoewel de auteurs erop wijzen dat deze evenzeer een marker kunnen zijn voor atherogeniciteit zoals LDL cholesterol dat is.

Lees onderstaand het volledige artikel.

Elevated nonfasting triglycerides -- but not cholesterol levels -- were associated with an increased risk of ischemic stroke, a large Danish study found.Compared with women whose nonfasting triglyceride levels were below 1 mmol/L, the hazard ratio for ischemic stroke in women whose triglycerides were 5 mmol/L or higher was 3.9 (95% CI 1.3 to 11.1, P for trend <0.001), according to Marianne Benn, MD, PhD, of Copenhagen University Hospital, and colleagues. And for men, the hazard ratio for those with the highest levels of triglycerides was 2.3 (95% CI 1.2 to 4.3, P for trend =0.001) compared with those with the lowest levels, the researchers reported online in the Annals of Neurology. Current stroke prevention guidelines provide advice on target cholesterol, but not nonfasting triglycerides. Yet, Benn and colleagues pointed out, "Elevated nonfasting triglycerides are markers of elevated levels of cholesterol in lipoprotein remnants thought to be atherogenic in the same way as low-density lipoprotein (LDL) cholesterol, by accumulation in the arterial wall."

To explore a possible association between nonfasting triglycerides and ischemic stroke, the researchers analyzed data from the Copenhagen City Heart Study, which included 7,579 women and 6,372 men who had measurements of cholesterol and triglycerides at baseline between 1976 and 1978. Mean age was 54. Median level of nonfasting triglycerides at baseline was 1.3 mmol/L in women and 1.7 mmol/L in men. Corresponding levels of cholesterol were 6.2 mmol/L and 5.9 mmol/L, respectively.
 

At baseline, none of the participants were using lipid-lowering therapy. During a median follow-up of 26 years, 837 men and 837 women had ischemic strokes. Analysis of the ischemic stroke outcome according to levels of nonfasting triglycerides revealed that, compared with levels below 1 mmol/L, risk rose increasingly beginning with levels from 1 to 1.99 mmol/L, when for women the hazard ratio was 1.2 (95% CI 0.9 to 1.7). For men, the hazard ratio at that level of triglycerides also was 1.2 (95% CI 0.8 to 1.7). In contrast, higher levels of cholesterol were not associated with increased risk for women, and only in men whose cholesterol was 9 mmol/L or higher was risk increased, compared with men whose levels were below 5 mmol/L (HR 4.4, 95% CI 1.9 to 10.6). The investigators suggested that a likely reason for the risk associated with nonfasting triglycerides is that they "are a marker of elevated lipoprotein remnant cholesterol." Remnants, they explained, are particles of lipoprotein that form during the metabolism of the large lipoprotein particles known as chylomicrons, and particles of very-low-density lipoprotein. These particles are capable of penetrating arterial walls, where they can deposit cholesterol in the intima. Ultimately, this can lead to atherosclerosis. The researchers acknowledged that it was "difficult to explain" why cholesterol did not appear to be associated with risk of ischemic stroke except in men with the highest levels, since increases in both cholesterol and triglycerides increase the risk of other disorders such as myocardial infarction. The difference may relate to pathogenesis of the different conditions, they suggested. "Myocardial infarction is mainly a thrombotic disease and ischemic stroke is mainly an embolic disease, and this difference in etiology could be part of the explanation of the findings," they wrote. There also may be other factors contributing to ischemic stroke, such as disease of the heart valves.

Limitations to the study included the homogeneity of the population studied and blood sampling being done at inconsistent times of day. "Our findings suggest that levels of nonfasting triglycerides should be included in guidelines as a marker of elevated levels of remnant lipoprotein cholesterol," they
advised.
1. Varbo A, et al "Nonfasting triglycerides, cholesterol, and ischemic stroke in the general population" Ann Neurol 2011; DOI:10.1002/ana.22384.