Table 1.
(a): Characteristics of 340 CARDIA participants that never reported smoking tobacco with participation at the Year 30 MRI sub-study excluding participants with a history of stroke or TIA. (b): Characteristics of 308 CARDIA participants that ever reported smoking tobacco with participation at the Year 30 MRI sub-study excluding participants with a history of stroke or TIA.
| Never Tobacco Smoking:Variable | All | Never | Ever Cannabis Usea | p-valueb | ||
|---|---|---|---|---|---|---|
| 1 day to 0.5 cannabis years | 0.5 to < 2 cannabis years | > 2 cannabis years | ||||
| N (%) | 340 (100.0%) | 75 (22.1%) | 175 (51.5%) | 59 (17.4%) | 31 (9.1%) | |
| (a) | ||||||
| Demographics | ||||||
| Age years, mean (SD) | 55 (3) | 55 (4) | 55 (4) | 56 (4) | 56 (4) | 0.14 |
| Race, N (Col. %)c | 0.032 | |||||
| Black women | 67 (19.7%) | 20 (26.7%) | 37 (21.1%) | 4 (6.8%) | 6 (19.4%) | |
| Black men | 48 (14.1%) | 12 (16.0%) | 21 (12.0%) | 9 (15.3%) | 6 (19.4%) | |
| White women | 110 (32.4%) | 23 (30.7%) | 63 (36.0%) | 20 (33.9%) | 4 (12.9%) | |
| White men | 115 (33.8%) | 20 (26.7%) | 54 (30.9%) | 26 (44.1%) | 15 (48.4%) | |
| Education years, mean (SD) | 16 (2) | 16 (3) | 17 (2) | 16 (2) | 16 (2) | 0.24 |
| Study center, N (Col. %) | <0.001 | |||||
| Birmigham, AL | 97 (28.5%) | 37 (49.3%) | 43 (24.6%) | 14 (23.7%) | 3 (9.7%) | |
| Minneapolis, MI | 109 (32.1%) | 27 (36.0%) | 53 (30.3%) | 24 (40.7%) | 5 (16.1%) | |
| Oakland, CA | 134 (39.4%) | 11 (14.7%) | 79 (45.1%) | 21 (35.6%) | 23 (74.2%) | |
| Substance use exposure | ||||||
| Tobacco smoking, N (Col. %) | n/a | |||||
| never smoker | 340 (100.0%) | 75 (100.0%) | 175 (100.0%) | 59 (100.0%) | 31 (100.0%) | |
| past smoker | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | |
| current smoker | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | |
| Cumulative tobacco exposure among ever smokers/ tobacco pack-yearse | 0 | 0 | 0 | 0 | 0 | n/a |
| Alcohol use | 13.4 (20.4) | 4.3 (9.3) | 11.7 (14.5) | 17.5 (17.0) | 36.7 (43.5) | <0.001 |
| Cumulative alcohol use among ever drinkers/ drink-yearsf, mean (SD) | ||||||
| Cum. lifetime binge episodesg/ binge drinking days, mean (SD) | 160 (464) | 72 (350) | 103 (236) | 158 (278) | 708 (1143) | <0.001 |
| Cannabis use status, N (Col. %)d | <0.001 | |||||
| never user | 75 (22.1%) | 75 (100.0%) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | |
| past user | 231 (67.9%) | 0 (0.0%) | 174 (99.4%) | 47 (79.7%) | 10 (32.3%) | |
| current user | 34 (10.0%) | 0 (0.0%) | 1 (0.6%) | 12 (20.3%) | 21 (67.7%) | |
| Cumulative cannabis exposure / cannabis yearsa, mean (SD) | 1.2 (3.6) | 0.0 (0.0) | 0.07 (0.08) | 1.2 (0.5) | 9.9 (7.9) | <0.001 |
| Illicit drug use | <0.001 | |||||
|
Current useh −Cocaine, crack, speed or methamphetamine, N (Col. %) |
7 (2.1%) | 0 (0.0%) | 1 (0.6%) | 0 (0.0%) | 6 (19.4%) | |
| −Heroin, N (Col. %) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | |
|
Anthropomorphic variable BMIi, mean (SD) |
28.0 (4.6) | 28.8 (4.5) | 27.5 (4.7) | 28.6 (4.7) | 27.9 (4.6) | 0.13 |
|
Psychological variable Depression, current CES-D > = 16/30j, N (Col. %) |
161 (12.6%) | 34 (11.3%) | 82 (11.8%) | 26 (14.7%) | 19 (18.3%) | 0.48 |
| Ever Tobacco Smoking: Variable | All | Never | Ever Cannabis Usea | p-valueb | ||
|---|---|---|---|---|---|---|
| 1 day to 0.5 cannabis years | 0.5 to < 2 cannabis years | > 2 cannabis years | ||||
| N (%) | 308 (100.0%) | 18 (5.8%) | 105 (34.1%) | 98 (31.8%) | 87 (28.2%) | |
| (b) | ||||||
| Demographics | ||||||
| Age years, mean (SD) | 55 (3) | 54 (4) | 55 (3) | 56 (3) | 55 (4) | 0.06 |
| Race, N (Col. %)c | <0.001 | |||||
| Black women | 72 (23.4%) | 10 (55.6%) | 26 (24.8%) | 22 (22.4%) | 14 (16.1%) | |
| Black men | 69 (22.4%) | 2 (11.1%) | 19 (18.1%) | 12 (12.2%) | 36 (41.4%) | |
| White women | 3 (16.7%) | 42 (40.0%) | 34 (34.7%) | 12 (13.8%) | 91 (29.5%) | |
| White men | 76 (24.7%) | 3 (16.7%) | 18 (17.1%) | 30 (30.6%) | 25 (28.7%) | |
| Education years, mean (SD) | 15 (3) | 15 (3) | 156 (3) | 15 (2) | 14 (2) | <0.001 |
| Study center, N (Col. %) | 0.002 | |||||
| Birmigham, AL | 75 (24.4%) | 12 (66.7%) | 27 (25.7%) | 19 (19.4%) | 17 (19.5%) | |
| Minneapolis, MI | 141 (45.8%) | 5 (27.8%) | 46 (43.8%) | 48 (49.0%) | 42 (48.3%) | |
| Oakland, CA | 92 (29.9%) | 1 (5.6%) | 32 (30.5%) | 31 (31.6%) | 28 (32.2%) | |
| Substance use exposure | ||||||
| Tobacco smoking, N (Col. %) | <0.001 | |||||
| never smoker | ||||||
| past smoker | 226 (73.4%) | 14 (77.8%) | 82 (78.1%) | 81 (82.7%) | 49 (56.3%) | |
| current smoker | 82 (26.6%) | 4 (22.2%) | 23 (21.9%) | 17 (17.3%) | 38 (43.7%) | |
| Cumulative tobacco exposure among ever smokers/ tobacco pack-yearse, mean (SD) | 11.0 (12.5) | 7.9 (13.5) | 9.7 (12.64) | 10.3 (11.1) | 13.9 (13.2) | 0.002 |
| Alcohol use | 0.50 | |||||
| Cumulative alcohol use among ever drinkers/ drink-yearsf, mean (SD) | 30.6 (40.1) | 11.3 (16.9) | 18.7 (25.8) | 29.0 (32.2) | 50.80 (55.2) | |
| Cum. lifetime binge episodesg/ binge drinking days, mean (SD) | 509 (969) | 126 (255) | 195 (443) | 456 (721) | 1029 (1’444) | <0.001 |
| Cannabis use status, N (Col. %)d | <0.001 | |||||
| never user | 18 (5.8%) | 18 (100.0%) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | |
| past user | 220 (71.4%) | 0 (0.0%) | 104 (99.0%) | 81 (82.7%) | 35 (40.2%) | |
| current user | 70 (22.7%) | 0 (0.0%) | 1 (1.0%) | 17 (17.3%) | 52 (59.8%) | |
| Cumulative cannabis exposure / cannabis yearsa, mean (SD) | 2.5 (4.0) | 0.0 (0.0) | 0.1 (0.1) | 1.3 (0.5) | 7.3 (4.9) | <0.001 |
| Illicit drug use | 0.071 | |||||
|
Current useh −Cocaine, crack, speed or methamphetamine, N (Col. %) |
15 (4.9%) | 1 (5.6%) | 1 (1.0%) | 5 (5.1%) | 6 (9.2%) | |
| Heroin, N (Col. %) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | |
|
Anthropomorphic variable BMIi, mean (SD) |
28.0 (4.9) | 26.4 (5.7) | 27.9 (4.8) | 27.7 (4.8) | 28.9 (4.9) | 0.17 |
|
Psychological variable Depression, current CES-D > = 16/30j, N (Col. %) |
195 (16.5%) | 7 (14.9%) | 57 (13.9%) | 60 (15.8%) | 71 (20.6%) | 0.63 |
BMI body mass index, CARDIA coronary artery risk development in young adults study, Col. % column percentage, N number of participants, +-SD upper and lower limit of standard deviation.
aSelf-reported cumulative exposure to cannabis joints in cannabis-years; 1 cannabis-year of exposure = 365 days of cannabis use (1 year × 365 days/y).
bP-values are from Kruskal-Wallis rank test for age, years of education, pack-years, drink-years, age started smoking, and BMI, from a χ2 test for race, study site, current smoking status, CES-D, and cumulative binge drinking categories, and from a Fisher exact test for cannabis and illicit drug use categories. Significant p-values marked in bold.
cBy design, the CARDIA study sampled self-identified white men, white women, black men and black women in roughly equal numbers for participation in the study.
dCategories based on the answer to the question: “During the last 30 days, on how many days did you use marijuana?”
eSelf-reported cumulative exposure to cigarettes in pack-years: 1 pack-year of exposure = 7300 cigarettes (1 year × 365 days/y × 1 pack/d × 20 cigarettes/pack).
fCumulative alcohol use in drink-years: 1 drink-year is the total amount of ethanol consumed by a person who had 1 alcoholic drink per day for 1 year (1 drink-year = 17.24 ml of ethanol/drink x 1 drink/d x 365 days/y = 6292.6 ml of ethanol).
gBinge drinking days, defined as ≥5 drinks per day. If bingeing were to be constant over 30 years in one individual, 300 binge drinking days would correspond to 10 days of bingeing each year for 30 years.
hCurrent use, defined as any use within the last 30 days. Cocaine included all forms of cocaine, like crack, powder, free base; amphetamines included speed, uppers, and methamphetamines.
iCalculated as weight in kilograms divided by height in meters squared.
jSelf-reported depression was measured every five years, starting at the Year 5 visit, on the Center for Epidemiologic Studies Depression scale (CES-D)0.18 A score of ≥16 was the cut-off for both sexes, indicating clinically significant depressive symptoms.