Water-pipe smoking increases risk for coronary artery calcium progression
In a new study, adults who reported exclusive water-pipe smoking had a higher risk for coronary heart disease, based on the presence and extent of coronary artery calcium, compared with nonsmokers.
“Water-pipe smoking is a traditional way of smoking tobacco that is most common in Middle Eastern countries but is gaining popularity worldwide, especially among young adults,” Hassan A. Chami, MD, physician in the department of internal medicine at the American University of Beirut, Lebanon, and colleagues wrote in CHEST. “The water-pipe smoking epidemic is relatively recent, especially among young individuals; however, the overt health effects of smoking are generally delayed. It is therefore advantageous to examine the association between water-pipe smoking and measures of subclinical CHD, such as coronary artery calcium.”
The goal of the study was to evaluate the association of exclusive water-pipe smoking with coronary artery calcium (CAC) progression — a marker for coronary heart disease — in a community-based sample of exclusive water-pipe smokers (n = 175) in Lebanon and Qatar compared with nonsmokers (n = 170).
The researchers used a validated questionnaire to assess water-pipe smoking; multidetector CT scan to assess CAC score; and regression analyses adjusted for CHD risk factors to assess the association of water-pipe smoking with the presence and extent of CAC.
Water-pipe smokers and nonsmokers had similar baseline characteristics. Median age of water-pipe smokers was 53.7 years vs. 53.8 years for nonsmokers, BMI was 29.7 kg/m² among water-pipe smokers vs. 28.8 kg/m² among nonsmokers and 33.1% of water-pipe smokers were women vs. 31.8% of nonsmokers. Conversely, compared with nonsmokers, water-pipe smokers were more likely to report use of lipid-lowering medications (6.5% vs. 13.1% and a family history of heart disease (42.4% vs. 57.7%).
Water-pipe smokers reported smoking an average of 2.3 water pipes per day during an average of 27.9 years, for an average of 65 water-pipe-years. Nearly all water-pipe smokers reported smoking daily. However, none of the water-pipe smokers reported concurrent or previous use of cigarettes or other forms of tobacco smoking, whereas 45% of nonsmokers reported exposure to secondhand smoking.
The extent of CAC was signicantly associated with the extent of water-pipe smoking as measured by smoking duration ( = .17 per year; 95% CI, 0.05-0.29; P = .004) or the product of smoking duration and the number of water pipes smoked daily ( = 0.04 per water-pipe-year; 95% CI, 0.003-0.07; P = .03).
CAC was present in 41% of water-pipe smokers when compared with 28% of nonsmokers (P = .01), for an average CAC score ± SD of 90.6 ± 400.3 Agatston units (AUs) in water-pipe smokers vs. 52.4 ± 218.6 AUs in nonsmokers. Moreover, log(CAC) was signicantly higher among water-pipe smokers (P = .02).
The 10-year risk for coronary heart disease was 7.1% among water-pipe smokers vs. 4% among nonsmokers (P < .0001).
In analyses adjusted for potential confounders, water-pipe smokers had signicantly higher adjusted odds for CAC (OR = 2.20; 95% CI, 1.20-4.01; P = .01) and for classification in the highest CHD risk category — dened as CAC greater than 300 AUs (OR = 3.41; 95% CI, 1.08-10.77; P = .04) or CAC greater than 75% of age, gender and race-predicted (OR = 3.11; 95% CI, 1.55-6.24; P = .001) compared with nonsmokers.
“This study suggests that water-pipe smoking is a signicant risk factor for CHD and strengthens the evidence that links water-pipe smoking with important adverse health outcomes,” Chami and colleagues concluded. “Our ndings justify measures to curb water-pipe smoking and raise awareness about its adverse health effects. Prospective research that longitudinally evaluates CHD risk in water-pipe smokers would further enhance the evidence linking water-pipe smoking and CHD risk,” – by Jennifer Southall
Disclosures: The authors report no relevant financial disclosures. The study was supported by a grant from the Qatar National Research Fund, National Priorities Research Program.