Table 2.
Association between tobacco use and self-reported heart disease in the Golestan Cohort Study
| Tobacco use† | All participants (%) |
HD cases (%) |
Participants without HD (%) |
Unadjusted OR (95% CI) |
Adjusted OR (95% CI) * |
|---|---|---|---|---|---|
| Water-pipe smoking | |||||
| Ever vs. never use | |||||
| Never | 49,489 (98.9) | 2990 (98.1) | 46,499 (99.0) | Reference | Reference |
| Ever | 525 (1.1) | 51 (1.9) | 474 (1.0) | 1.67 (1.25–2.24) | 1.09 (0.80–1.48) |
| Moderate-high vs. never-low use | |||||
| ≤ 50 water-pipe-years | 49,894 (99.8) | 3022 (99.4) | 46,872 (99.8) | Reference | Reference |
| > 50 water-pipe-years | 120 (0.2) | 19 (0.6) | 101 (0.2) | 2.92 (1.78–4.77) | 1.83 (1.10–3.07) |
| Cumulative use | |||||
| Never | 49,489 (98.9) | 2990 (98.3) | 46,499 (99.0) | Reference | Reference |
| ≤ 50 water-pipe-years | 405 (0.8) | 32 (1.0) | 373 (0.8) | 1.33 (0.93–1.91) | 0.87 (0.60–1.28) |
| 50.1 – 100 | 52 (0.1) | 6 (0.2) | 46 (0.1) | 2.03 (0.86–4.74) | 1.25 (0.52–3.03) |
| 100.1 – 180 | 43 (0.1) | 5 (0.2) | 38 (0.1) | 2.05 (1.03–2.80) | 1.49 (0.57–3.87) |
| > 180 | 25 (0.1) | 8 (0.3) | 17 (0.04) | 6.39 (2.65–15.41) | 3.75 (1.52–9.22) |
| P trend: <0.001 | P trend: 0.04 | ||||
| Cigarette smoking | |||||
| Ever vs. never use | |||||
| Never | 41,445 (82.9) | 2405 (79.7) | 39,040 (83.1) | Reference | Reference |
| Ever | 8555 (17.1) | 614 (20.3) | 7941 (16.9) | 1.26 (1.14–1.38) | 1.63 (1.45–1.83) |
| Moderate-high vs. never-low use | |||||
| ≤5 pack-years | 44,187 (88.4) | 2559 (85.3) | 41,628 (88.6) | Reference | Reference |
| > 5 pack-years | 5813 (11.6) | 460 (14.7) | 5353 (11.4) | 1.40 (1.26–1.55) | 1.76 (1.55–1.99) |
| Cumulative use | |||||
| Never | 41,445 (82.9) | 2405 (79.7) | 39,040 (83.1) | Reference | Reference |
| ≤5 pack-years | 2742 (5.5) | 154 (5.1) | 2588 (5.5) | 0.97 (0.82–1.14) | 1.26 (1.05–1.52) |
| 5.1 –10 | 1260 (2.5) | 73 (2.4) | 1187 (2.5) | 1.00 (0.79–1.27) | 1.43 (1.11–1.84) |
| 10.1 – 20.0 | 1798 (3.6) | 121 (4.0) | 1677 (3.6) | 1.17 (0.97–1.41) | 1.73 (1.41–2.13) |
| > 20 | 2755 (5.5) | 266 (8.8) | 2489 (5.3) | 1.73 (1.52–1.98) | 2.04 (1.74–2.38) |
| P trend: <0.001 | P trend: <0.001 | ||||
| Nass chewing | |||||
| Ever vs. never use | |||||
| Never | 46,264 (92.5) | 2775 (92.5) | 43,489 (92.5) | Reference | Reference |
| Ever | 3726 (7.5) | 225 (7.5) | 3501 (7.5) | 1.01 (0.88–1.16) | 0.85 (0.73–1.00) |
| Moderate-high vs. never-low use | |||||
| ≤50 nass-years | 48,026 (96.1) | 2859 (95.3) | 45,167 (96.1) | Reference | Reference |
| > 50 nass-years | 1964 (3.9) | 141 (4.7) | 1823 (3.9) | 1.22 (1.03–1.46) | 0.95 (0.79–1.15) |
| Cumulative use | |||||
| Never | 46,264 (92.5) | 2775 (92.5) | 43,489 (92.5) | Reference | Reference |
| ≤50 nass-years | 1762 (3.5) | 84 (2.8) | 1678 (3.6) | 0.78 (0.63–0.98) | 0.75 (0.60–0.95) |
| 50.1 –100 | 635 (1.3) | 43 (1.4) | 592 (1.3) | 1.14 (0.83–1.56) | 0.98 (0.71–1.36) |
| 100.1 –180 | 532 (1.1) | 35 (1.2) | 497 (1.0) | 1.10 (0.78–1.56) | 0.90 (0.62–1.28) |
| > 180 | 797 (1.6) | 63 (2.1) | 734 (1.6) | 1.35 (1.04–1.74) | 0.91 (0.69–1.20) |
| P trend: 0.09 | P trend: 0.24 | ||||
CI, confidence interval; HD, heart disease; OR, odds ratio. Numbers may not add up to the total numbers due to missing data in some variables.
All results for each tobacco product were adjusted for cumulative use of the other products listed in this table, as well as for age, sex, ethnicity, place of residence, education level, wealth, physical activity, body mass index, hypertension, and self-reported diabetes (these variables were as shown in Table 1).
Among HD cases, those who started the use of the tobacco product after receiving a diagnosis of HD were excluded from the analyses related to the respective product; 100 water-pipe-years, for example, indicates water-pipe use equivalent to use 10 times per day for 10 years (or use 5 times per day for 20 years).