Passive smoking increases platelet activation in healthy people

"It is well known that passive smoking is harmful for cardiovascular health, but the mechanism has not yet been discovered," said Dr Kaya. "We investigated the effects of passive smoking on the levels of three parameters – mean platelet volume (MPV), carboxyhemoglobin (COHb) and lactate - in an effort to further understand this mechanism. We also looked at the correlation between the three parameters."

Mean platelet volume (MPV) is a well established indicator of platelet activation that is increased in acute thrombotic events. It is suspected that carbon monoxide (CO) plays a major role in cigarette smoke-induced cardiovascular diseases. When CO binds with (Hb) in it is called COHb. Lactate accumulates in the blood when the supply of oxygen to blood cells is limited.

For the study, 55 healthy nonsmoker volunteers (males 30%; mean age 26±5 years) were prospectively enrolled. for measurements of MPV, COHb and lactate were taken at baseline and after spending one an hour in a .

The of all three parameters were statistically higher after subjects were exposed to passive smoking (see figure 1). COHb increased from 0.8±0.3% at baseline to 1.2±0.4% after one hour in a smoking room (p=0.001). Lactate increased from 0.70±0.2mmol/L to 2.2±0.9mmol/L (p=0.001). MPV increased from 7.8±0.4 femtolitres (fL) to 8.5±0.6fL (p= 0.001). Dr Kaya said: "These results show that passive smoking increases platelet activation and increases CO and lactate levels in the blood."

The researchers found significant correlations between MPV and COHb levels (r= 0.55, p=0.0001) and between MPV and lactate levels (r= 0.65, p=0.0001) after smoking. There was also a remarkable relation between COHb and lactate levels after smoking (r= 0.78, p=0.0001). Dr Kaya said: "Previous studies have suggested that the chemicals in cigarette smoke, especially nicotine and CO, increase platelet-activating factor. The correlations found in our study suggest that the CO in cigarette smoke also increases MPV levels. It is likely that levels increased because oxygen levels in the blood dropped as CO increased."

He concluded: "We have shown that 1 hour exposure to passive smoking increases platelet activation, which could be the mechanism by which it contributes to increased risk of thrombotic events in healthy people. It is likely that prolonged exposure to passive smoking could have even greater effects. Healthy people should avoid exposure to passive smoking so that they do not increase their risk of thrombotic events."

add to favorites email to friend print save as pdf

Related Stories

Addressing how cigarettes cause cardiovascular disease

Oct 10, 2011

Although cigarette smoking has long been linked to cardiovascular disease, scientists are still on the lookout for insights into how smoking causes this disease. A team of researchers at Pacific Northwest ...

Recommended for you

New treatment for inherited cholesterol

4 hours ago

At the London Olympics in 2012, South African swimmer Cameron van den Burgh dedicated his world record-breaking win in the 100m breast stroke to one of his biggest rivals and closest friends, Alexander Dale ...

Alternate approach to traditional CPR saves lives

11 hours ago

A new study shows that survival and neurological outcomes for patients in cardiac arrest can be improved by adding extracorporeal membrane oxygenation (ECMO) when performing cardiopulmonary resuscitation (CPR). The study ...

User comments