Gepaard gaande met allerhande waarschuwingen en ‘maren’ doet de wetenschap kond van een positieve eigenschap van roken: zware rokers hebben veel minder last van terugval na de behandeling van hart- en vaatziekten dan lichte rokers of niet-rokers.
Volgens de wetenschappers zou het kunnen liggen aan de inname van koolmonoxide bij het roken. Ze vinden dat daar meer onderzoek naar moet worden gedaan.
“In a paradoxical way, smoking may actually be helping or in some way protecting against restenosis [renarrowing of the arteries], but clearly the long-term effects of smoking are going to be deleterious”
People with peripheral artery disease (PAD) have a narrowing or blockage in the arteries, which means that not enough oxygen gets to the arms or legs. Generally, the condition is treated with angioplasty, during which a physician inserts a small catheter through the blood vessel and threads it to the site of the obstruction, where it is inflated to prop open the vessel. Sometimes a stent, or wire-mesh cylinder, is left inside the artery to prevent it from closing up again.
However according to the study, up to 60 percent of the patients who have the procedure will experience restenosis, which is a natural response of the body to this kind of injury, and will have to go through the whole process again.
The researchers looked at 650 patients with PAD who had angioplasty (with or without stents) to open arteries leading to the legs. The patients were grouped according to their smoking status: nonsmokers; light smokers (one to nine cigarettes a day); habitual smokers (10 to 20 cigarettes daily); or heavy smokers (more than 20 cigarettes daily).
At the end of both six months and a year, the researchers found: heavy smokers had a 16 percent rate of renarrowing at six months and 29 percent at one year; those who smoked 10 to 20 cigarettes a day had rates of 20 percent and 35 percent, respectively; and for nonsmokers, the rates were 28 percent at six months and 54 percent at one year.
It’s not the cigarettes per se but the carbon monoxide that appears to account for these results, the researchers said.
“Most probably it’s the CO which exerts the protective effect,” Schillinger said. Carbon monoxide is known to dilate blood vessels and also suppress the growth of smooth muscle cells in the wall of the artery.