TABLE 2 ] .
Study Type | Cohort Size, Location, Racial Features | Subjects With Cancer and Control Subjects | How Cannabis Use Assessed and Quantitateda | Approximate Cannabis Use Among Cannabis Smokers | Years of Cannabis Use | Main Findings and Observations | Reference |
Case-control cohort | 403 New Zealand residents |
79 lung cancer 324 control |
Duration of cannabis use, joint-y, pack-y tobacco use | 12 of 79 cases with > 10.5 joint-y compared with four of 324 control subjects | 2001-2005 | After adjustment for family history and pack-y tobacco, relative risk for lung cancer was 1.08 (95% CI, 1.02-1.15) per joint-y cannabis smoking | 16 |
Cross-sectional | 29,195 National surveys on drug use and health, United States Adjusted for race/ethnicity |
Lung cancer by duration of cannabis use: Never = 9 ≤ 1 y = 23 2-10 y = 23 ≥ 11 y = 67 |
Duration of cannabis use (y); daily tobacco use also ascertained for use in models | Not reported | 2005-2007 | After adjustment, cannabis use of ≥ 11 y associated with OR for lung cancer development of 7.87 (95% CI, 1.28-48.4) | 18 |
Longitudinal evaluation over 40 y of single cohort | 49,321 Swedish men born in 1949-1951 conscripted in 1969-1970 for military service |
189 lung cancer 49,132 control |
Ever or never use of cannabis, lifetime frequency of cannabis use, No. tobacco cigarettes per day | 5,156 ever cannabis users 831 of 5,156 (16%) reported > 50 times of use 515 of 831 (62%) also smoked > 10 cigarettes/d |
1969-2009 | After adjusting for tobacco and alcohol consumption, smoking cannabis > 50 times was associated with a hazard ratio of 2.12 (95% CI, 1.08-4.14) for lung cancer development over 40 y; ever use was not associated with an increased hazard ratio for lung cancer | 17 |
Analysis of pooled data from six case-control studies | 5,144 International Lung Cancer Consortium: United States, Europe, New Zealand 79% white, 11% black |
2,159 lung cancer 2,985 control |
Lifetime cannabis use, joint-y; 86% of habitual cigarette smokers also used cannabis | 10% of patients with lung cancer were habitual cannabis users 6% with ≥ 10 joint-y |
1999-2013 | Little or no association between intensity, duration, or cumulative use of cannabis and risk of lung cancer development; pooled OR for association between cannabis smoking (habitual vs nonhabitual) and lung cancer risk was 0.95 (95% CI, 0.66-1.38) | 19 |
Pack-y = 1 pack/d tobacco cigarettes × 20 cigarettes/pack × 365 d/y; joint-y = 1 joint/d × 365 d/y.