Background: Cigarette smoking is described as ‘probably the most addictive and dependence-producing form of object-specific self gratification known to man’. It is estimated that about half of all regular cigarette smokers will eventually be killed by their habit^[1].[2]. Smoking increases the absolute number of deaths from lung cancer, cancer of other respiratory sites, chronic bronchitis/emphysema and cor pulmonale. Deaths from ischaemic heart disease and cerebrovascular disease are advanced by smoking ^[3]

Aims & Objectives: To investigate the relationship between monocyte to high-density lipoprotein cholesterol (HDL-C) ratio (MHR) and cigarette smoking.

Materials & Methods: About 50 participants who smoke and 50 healthy subjects with no history of smoking who presented to the Department of Medicine, Kempegowda Institute of Medical Sciences, Bangalore were enrolled in this study. Complete blood count and lipid profile were analysed in all study participants. Smoking habits were calculated according to number of cigarettes smoked per day, in pack years.

Results: According to Pearson’s correlation analysis there was a weak but positive correlation between pack year and MHR in the smokers group, and there was a moderate positive correlation between the number of cigarettes smoked daily and MHR in the group. MHR levels were significantly elevated in smokers 15.71 (12.02-20.00) compared to non-smokers 11.17 (8.50–14.16). 

Conclusions: Elevated MHR is a good indicator of a systemic inflammatory response in smokers. Smokers who have high MHR levels can easily be identified and could benefit from preventive treatment.

Keywords: smoking; monocyte to high-density lipoprotein cholesterol.

1. Carter, B.D.; Freedman, N.D.; Jacobs, E.J. Smoking and mortality—Beyond established causes. N. Engl. J. Med. 2015, 372, 2168–2170.
2. World Health Organisation: Report on the Global Tobacco Epidemic. Implementing Smoke-Free Environments. 2009. Available online: http://www.who.int/tobacco/mpower/2009/en (accessed on 25 December 2017).
3. Collishaw, N.E.; Lopez, A.D. Prevalence of cigarette smoking in developing countries. Tob. Control 1995, 4, 327.
4. Sgambato, J.A.; Jones, B.A.; Caraway, J.W.; Prasad, G.L. Inflammatory profile analysis reveals differences in cytokine expression between smokers, moist snuff users, and dual users compared to non-tobacco consumers. Cytokine 2017.
5. Lee, J.; Taneja, V.; Vassallo, R. Cigarette smoking and inflammation cellular and molecular mechanisms. J. Dent. Res. 2012, 91, 142–149.
6. Ancuta, P.; Wang, J.; Gabuzda, D. CD16+ monocytes produce IL-6, CCL2, and matrix metalloproteinase-9 upon interaction with CX3CL1-expressing endothelial cells. J. Leukoc. Biol. 2006, 80, 1156–1164.
7. Heeschen, C.; Weis, M.; Cooke, J.P. Nicotine promotes arteriogenesis. J. Am. Coll. Cardiol. 2003, 41, 489–496.
8. Wang, Z.; Wang, D.; Wang, Y. Cigarette smoking and adipose tissue: The Emerging role in progression of atherosclerosis. Mediat. Inflamm. 2017, 2017, 3102737.
9. Ghattas, A.; Griffiths, H.R.; Devitt, A.; Lip, G.Y.; Shantsila, E. Monocytes in coronary artery disease and atherosclerosis: Where are we now? J. Am. Coll. Cardiol. 2013, 62, 1541–1551
10. Gratchev, A.; Sobenin, I.; Orekhov, A.; Kzhyshkowska, J. Monocytes as a diagnostic marker of cardiovascular diseases. Immunobiology 2012, 217, 476–482
11. Murphy, A.J.; Chin-Dusting, J.P.; Sviridov, D.; Woollard, K.J. The anti inflammatory effects of high density lipoproteins. Curr. Med. Chem. 2009, 16, 667–675.

Dr Tharuni Latha. A

Postgraduates in Medicine, Kempegowda Institute of Medical Science Vvpuram Bangalore