Effect of smoking reduction and cessation on cardiovascular risk factors.

This open study examined the effect of smoking reduction and smoking cessation on established cardiovascular risk factors. Fifty-eight healthy adult smokers (smoking >or=15 cigarettes/day for at least 3 years) were provided with nicotine nasal spray (to be used ad libitum) and asked to stop smoking. The primary goal during the first 8 weeks, however, was to reduce their daily smoking by at least 50%. Subjects were then followed for another 8 weeks; at this point, 33 participants had successfully stopped smoking. Cardiovascular risk factors including fibrinogen, hemoglobin, hematocrit, triglycerides, and cholesterol were measured at baseline and at 9 and 17 weeks. After 8 weeks of smoking reduction, the mean number of cigarettes smoked per day had decreased from 21.5 +/- 0.6 (baseline) to 10.8 +/- 0.6 (p < 0.001). This was accompanied by significant improvements in fibrinogen (from 2.9 +/- 0.1 g/l at baseline to 2.6 +/- 0.1 g/l, p = 0.011), white blood cells (from 7.0 +/- 0.4 to 6.2 +/- 0.3 x 10(9)/l, p = 0.005) and the high-density/low-density lipoprotein (HDL/LDL) ratio (0.33 +/- 0.03 to 0.37 +/- 0.03, p < 0.005). Following 8 weeks of abstinence from smoking, the mean white blood cell count was further reduced (to 6.1 +/- 0.3 x 10(9)/l, p = 0.026 vs. baseline) and there were also significant improvements in HDL (from 1.16 +/- 0.06 mmol/l at baseline to 1.32 +/- 0.06, p < 0.001) and LDL (from 3.78 +/- 0.16 mmol/l at baseline to 3.52 +/- 0.17, p = 0.015). In conclusion, 8 weeks of smoking reduction resulted in clinically significant improvements in established cardiovascular risk factors. These improvements were even greater after an additional period of abstinence from smoking.