The Association of Water-Pipe Smoking and Coronary Artery Calcium in a Community-Based Sample

Background Water-pipe smoking is increasing in popularity, driven partly by a perception of reduced harm compared with cigarette smoking. This study evaluates the association of water-pipe smoking with coronary artery calcium (CAC), a marker of coronary heart disease (CHD) risk, in a community-based sample. Methods A total of 175 exclusive water-pipe smokers and 170 nonsmokers, ≥ 35 years of age, were recruited from the community in Lebanon and Qatar. Water-pipe smoking was assessed using a validated questionnaire. CAC score was assessed using multidetector CT scan. The association of water-pipe smoking with the presence and extent of CAC was evaluated using regression analyses adjusted for CHD risk factors. Results CAC was present in 41% of water-pipe smokers vs 28% of nonsmokers ( P  = .01), with an average CAC score ± SD of 90.6 ± 400.3 Agatston units (AUs) in water-pipe smokers and 52.4 ± 218.6 AUs in nonsmokers. In adjusted analyses, water-pipe smokers had significantly higher adjusted odds of having CAC (OR = 2.20; 95% CI, 1.20-4.01; P  = .01) and being in the high CHD risk category defined by CAC > 300 AUs (OR = 3.41; 95% CI, 1.08-10.77; P  = .04) or CAC > 75% of age, sex, and race-predicted (OR = 3.11; 95% CI, 1.55-6.24; P  = .001) than nonsmokers. CAC extent was significantly associated with water-pipe smoking extent measured by smoking duration (β = 0.17/year; 95% CI, 0.05-0.29; P  = .004) or the product of smoking duration and the number of water pipes smoked daily (β = 0.04/water-pipe-year; 95% CI, 0.003-0.07; P  = .03). Conclusions Exclusive water-pipe smoking was associated with the presence and extent of CAC, with twice the risk of having CAC and three times the risk of being in the high CHD risk category while accounting for other risk factors.