We reached out to 3,725 unique individuals of 7,356 potentially eligible patients (2,625 via EHR messaging and 1,100 via mailed invitation; Fig. 1). A total of 541 patients met study inclusion criteria and answered the survey (14% response rate); due to missing data or skip pattern failures, 523 were retained for the final analytic sample. We examined sociodemographic variables (age, sex at birth, race and ethnicity) that were associated with non-response (data not shown). Individuals who were more likely to complete the survey were non-white and older than 80 years.
The population weighted and unweighted characteristics of our enrolled sample are summarized in Table 1. Fifty-four percent of our participants endorsed using cannabis at some point after their cancer diagnosis (hereafter referred to as cannabis users). Forty-two percent endorsed using during treatment and an additional 26.6% reported considering cannabis use at some point since their cancer diagnosis. In addition, 71.8% endorsed using cannabis at any time over the course of their life. In unadjusted analyses, the following sociodemographic characteristics were associated with cannabis use at any time following diagnosis: younger age (61.4 vs 65.8, p = 0.001), driven by a higher percentage of 18- to 44-year-olds who reported cannabis use (16.3% vs. 8.1%). A significantly higher proportion of those who used cannabis endorsed “finding it difficult to get by on my present income” (12.4% vs 4.4%, p = 0.016). Finally, there was an association with primary source of health insurance and cannabis use with a notable difference in the percentage of those that used cannabis and had Medicaid compared to those that did not use cannabis and had Medicaid (15.1% vs 5.7%, p = 0.005). There was also a higher percentage with private health insurance plans among those who did not use cannabis compared to those who did use cannabis (38.8% vs 31.8%, p = 0.005). There were no other significant differences based on demographic characteristics between the two groups (Table 1).
Table 1
Participant characteristics by endorsement of cannabis use anytime since their cancer diagnosis
Category
|
Level
|
Weighted
|
Unweighted
|
|
|
Overall
|
Yes
|
No
|
p
|
Overall
|
Yes
|
No
|
p
|
n
|
-
|
7218
|
3972
|
3246
|
|
523
|
287
|
236
|
|
Age, mean (SD)
|
-
|
63.38 (16.36)
|
61.40 (16.68)
|
65.80 (15.66)
|
0.001
|
63.72 (17.34)
|
61.42 (17.68)
|
66.51 (16.52)
|
0.001
|
Age, categorical, % (n)
|
|
|
|
|
0.006
|
|
|
|
0.002
|
18 to 44
|
12.6 (910)
|
16.3 (646)
|
8.1 (264)
|
|
14.0 (73)
|
18.1 (52)
|
8.9 (21)
|
|
45 to 54
|
35.3 (2549)
|
35.5 (1409)
|
35.1 (1140)
|
|
33.1 (173)
|
33.4 (96)
|
32.6 (77)
|
|
65 to 74
|
33.5 (2420)
|
33.7 (1340)
|
33.3 (1080)
|
|
32.7 (171)
|
32.8 (94)
|
32.6 (77)
|
|
75 or older
|
18.6 (1340)
|
14.5 (577)
|
23.5 (762)
|
|
20.3 (106)
|
15.7 (45)
|
25.8 (61)
|
|
Sex assigned at birth, % (n)
|
|
|
|
|
0.707
|
|
|
|
0.722
|
Male
|
44.2 (3187)
|
45.5 (1807)
|
42.5 (1380)
|
|
41.5 (217)
|
42.9 (123)
|
39.8 (94)
|
|
Female
|
52.7 (3804)
|
52.7 (2092)
|
52.7 (1712)
|
|
54.5 (285)
|
54.7 (157)
|
54.2 (128)
|
|
(Missing)
|
3.1 (226)
|
1.8 (73)
|
4.7 (154)
|
|
4.0 (21)
|
2.4 (7)
|
5.9 (14)
|
|
Gender, % (n)
|
|
|
|
|
0.437
|
|
|
|
0.444
|
Male
|
43.4 (3129)
|
44.8 (1779)
|
41.6 (1350)
|
|
40.7 (213)
|
42.2 (121)
|
39.0 (92)
|
|
Female
|
52.3 (3777)
|
51.6 (2050)
|
53.2 (1727)
|
|
54.1 (283)
|
53.7 (154)
|
54.7 (129)
|
|
Transgender
|
0.2 (11)
|
0.3 (11)
|
0.0 (0)
|
|
0.2 (1)
|
0.3 (1)
|
0.0 (0)
|
|
None of the above
|
0.4 (28)
|
0.7 (28)
|
0.0 (0)
|
|
0.4 (2)
|
0.7 (2)
|
0.0 (0)
|
|
(Missing)
|
3.8 (273)
|
2.6 (104)
|
5.2 (169)
|
|
4.6 (24)
|
3.1 (9)
|
6.4 (15)
|
|
Race x Ethnicity, % (n)
|
|
|
|
|
0.191
|
|
|
|
0.168
|
Hispanic or Latino
|
2.7 (194)
|
3.2 (129)
|
2.0 (65)
|
|
2.3 (12)
|
2.8 (8)
|
1.7 (4)
|
|
Not Hispanic or Latino, White
|
89.5 (6458)
|
90.5 (3594)
|
88.3 (2864)
|
|
88.5 (463)
|
89.9 (258)
|
86.9 (205)
|
|
Not Hispanic or Latino, Black
|
0.3 (25)
|
0.0 (0)
|
0.8 (25)
|
|
0.4 (2)
|
0.0 (0)
|
0.8 (2)
|
|
Not Hispanic or Latino, Asian
|
0.4 (26)
|
0.0 (0)
|
0.8 (26)
|
|
0.4 (2)
|
0.0 (0)
|
0.8 (2)
|
|
Not Hispanic or Latino, Other
|
3.5 (251)
|
2.9 (114)
|
4.2 (137)
|
|
3.8 (20)
|
3.1 (9)
|
4.7 (11)
|
|
(Missing)
|
3.7 (264)
|
3.4 (136)
|
3.9 (128)
|
|
4.6 (24)
|
4.2 (12)
|
5.1 (12)
|
|
Income, % (n)
|
|
|
|
|
0.081
|
|
|
|
0.082
|
Less than $35,000
|
21.8 (1570)
|
25.1 (996)
|
17.7 (575)
|
|
21.8 (114)
|
25.1 (72)
|
17.8 (42)
|
|
$35,000 to $74,999
|
25.6 (1848)
|
27.0 (1073)
|
23.9 (775)
|
|
25.4 (133)
|
26.8 (77)
|
23.7 (56)
|
|
$75,000 or more
|
42.1 (3041)
|
38.9 (1546)
|
46.0 (1494)
|
|
41.5 (217)
|
38.3 (110)
|
45.3 (107)
|
|
(Missing)
|
10.5 (759)
|
9.0 (357)
|
12.4 (401)
|
|
11.3 (59)
|
9.8 (28)
|
13.1 (31)
|
|
Feelings about household income, % (n)
|
|
|
|
|
0.016
|
|
|
|
0.022
|
Living comfortably on present income
|
49.9 (3600)
|
47.3 (1877)
|
53.1 (1722)
|
|
49.3 (258)
|
46.7 (134)
|
52.5 (124)
|
|
Getting by on present income
|
27.3 (1971)
|
28.1 (1114)
|
26.4 (856)
|
|
27.3 (143)
|
28.2 (81)
|
26.3 (62)
|
|
Finding it difficult on present income
|
8.8 (636)
|
12.4 (492)
|
4.4 (144)
|
|
8.8 (46)
|
12.2 (35)
|
4.7 (11)
|
|
Finding it very difficult on present income
|
5.7 (409)
|
6.4 (254)
|
4.8 (155)
|
|
5.5 (29)
|
6.3 (18)
|
4.7 (11)
|
|
(Missing)
|
8.3 (602)
|
5.9 (235)
|
11.3 (368)
|
|
9.0 (47)
|
6.6 (19)
|
11.9 (28)
|
|
Occupation Status, % (n)
|
|
|
|
|
0.087
|
|
|
|
0.083
|
Employed
|
31.0 (2236)
|
29.1 (1155)
|
33.3 (1081)
|
|
30.8 (161)
|
29.3 (84)
|
32.6 (77)
|
|
Unemployed
|
3.0 (219)
|
3.8 (149)
|
2.2 (70)
|
|
3.3 (17)
|
4.2 (12)
|
2.1 (5)
|
|
Homemaker
|
2.9 (208)
|
3.5 (139)
|
2.1 (69)
|
|
2.9 (15)
|
3.5 (10)
|
2.1 (5)
|
|
Student
|
1.1 (82)
|
1.4 (57)
|
0.8 (25)
|
|
1.3 (7)
|
1.7 (5)
|
0.8 (2)
|
|
Retired
|
44.6 (3221)
|
42.1 (1671)
|
47.8 (1550)
|
|
44.0 (230)
|
41.1 (118)
|
47.5 (112)
|
|
Disabled
|
11.4 (821)
|
14.6 (579)
|
7.5 (242)
|
|
10.9 (57)
|
13.9 (40)
|
7.2 (17)
|
|
Other (Specify):
|
1.9 (138)
|
2.5 (98)
|
1.2 (39)
|
|
1.9 (10)
|
2.4 (7)
|
1.3 (3)
|
|
(Missing)
|
4.1 (294)
|
3.1 (123)
|
5.3 (170)
|
|
5.0 (26)
|
3.8 (11)
|
6.4 (15)
|
|
Highest level of education completed, % (n)
|
|
|
|
|
0.273
|
|
|
|
0.297
|
Less than high school
|
2.0 (146)
|
2.1 (83)
|
1.9 (63)
|
|
1.9 (10)
|
2.1 (6)
|
1.7 (4)
|
|
High school diploma
|
8.9 (645)
|
9.3 (371)
|
8.5 (274)
|
|
9.0 (47)
|
9.4 (27)
|
8.5 (20)
|
|
Some college
|
25.8 (1865)
|
29.4 (1166)
|
21.5 (698)
|
|
25.2 (132)
|
28.6 (82)
|
21.2 (50)
|
|
Vocational training or 2-year degree
|
3.9 (283)
|
4.6 (184)
|
3.1 (99)
|
|
3.8 (20)
|
4.5 (13)
|
3.0 (7)
|
|
4-year college degree or more
|
56.0 (4039)
|
52.5 (2084)
|
60.2 (1955)
|
|
55.8 (292)
|
52.6 (151)
|
59.7 (141)
|
|
(Missing)
|
3.3 (239)
|
2.1 (84)
|
4.8 (155)
|
|
4.2 (22)
|
2.8 (8)
|
5.9 (14)
|
|
Has health coverage, % (n)
|
|
|
|
|
0.532
|
|
|
|
0.433
|
Yes
|
93.3 (6735)
|
93.6 (3719)
|
92.9 (3015)
|
|
92.4 (483)
|
92.7 (266)
|
91.9 (217)
|
|
No
|
3.2 (228)
|
3.6 (144)
|
2.6 (84)
|
|
3.3 (17)
|
3.8 (11)
|
2.5 (6)
|
|
(Missing)
|
3.5 (255)
|
2.7 (109)
|
4.5 (146)
|
|
4.4 (23)
|
3.5 (10)
|
5.5 (13)
|
|
Primary source of health coverage, % (n)
|
|
0.005
|
|
|
0.005
|
|
|
|
0.004
|
Private plan through employer, family member, or buys for self
|
34.9 (2522)
|
31.8 (1261)
|
38.8 (1260)
|
|
34.4 (180)
|
31.7 (91)
|
37.7 (89)
|
|
Medicare
|
40.8 (2943)
|
39.2 (1558)
|
42.7 (1385)
|
|
40.7 (213)
|
38.7 (111)
|
43.2 (102)
|
|
Medicaid or other state program
|
10.9 (785)
|
15.1 (599)
|
5.7 (185)
|
|
10.7 (56)
|
15.0 (43)
|
5.5 (13)
|
|
TRICARE (formerly CHAMPUS), VA, or Military
|
3.9 (282)
|
4.6 (183)
|
3.1 (100)
|
|
3.6 (19)
|
4.2 (12)
|
3.0 (7)
|
|
Some other source
|
1.1 (80)
|
1.7 (66)
|
0.4 (13)
|
|
1.1 (6)
|
1.7 (5)
|
0.4 (1)
|
|
(Valid skip)
|
6.7 (483)
|
6.4 (253)
|
7.1 (230)
|
|
7.6 (40)
|
7.3 (21)
|
8.1 (19)
|
|
(Missing)
|
1.7 (123)
|
1.3 (52)
|
2.2 (72)
|
|
1.7 (9)
|
1.4 (4)
|
2.1 (5)
|
|
Differences between the two groups on measures of pain, perception of general health and mood, are displayed in Table 2. Of these variables, higher pain severity, pain interference, and depressive symptomatology were all associated with cannabis use in univariate analyses (all p ≤ 0.001). General health was not associated with endorsement of cannabis use.
Table 2
Pain, General Health and Depression by Cannabis Use Since Diagnosis
Category
|
Level
|
Weighted
|
Unweighted
|
|
|
Overall
|
Yes
|
No
|
p
|
Overall
|
Yes
|
No
|
p
|
n
|
|
7218
|
3972
|
3246
|
|
523
|
287
|
236
|
|
Pain on average in the past week, % (n)
|
|
|
|
|
< 0.001
|
|
|
|
0.001
|
Mild: [0, 3]
|
64.4 (4645)
|
58.9 (2339)
|
71.1 (2306)
|
|
63.9 (334)
|
58.9 (169)
|
69.9 (165)
|
|
Moderate: [4, 6]
|
22.5 (1623)
|
28.7 (1140)
|
14.9 (484)
|
|
22.2 (116)
|
28.2 (81)
|
14.8 (35)
|
|
Severe: [7, 10]
|
8.0 (576)
|
9.8 (390)
|
5.8 (187)
|
|
8.2 (43)
|
10.1 (29)
|
5.9 (14)
|
|
(Missing)
|
5.2 (373)
|
2.6 (104)
|
8.3 (269)
|
|
5.7 (30)
|
2.8 (8)
|
9.3 (22)
|
|
During the past week, how has pain interfered with enjoyment of life, % (n)
|
|
|
|
|
< 0.001
|
|
|
|
< 0.001
|
Mild: [0, 3]
|
66.0 (4764)
|
60.2 (2389)
|
73.2 (2374)
|
|
65.6 (343)
|
60.3 (173)
|
72.0 (170)
|
|
Moderate: [4, 6]
|
19.0 (1370)
|
24.7 (982)
|
11.9 (388)
|
|
18.7 (98)
|
24.4 (70)
|
11.9 (28)
|
|
Severe: [7, 10]
|
9.5 (684)
|
11.8 (467)
|
6.7 (216)
|
|
9.6 (50)
|
11.8 (34)
|
6.8 (16)
|
|
(Missing)
|
5.6 (401)
|
3.4 (134)
|
8.2 (267)
|
|
6.1 (32)
|
3.5 (10)
|
9.3 (22)
|
|
During the past week, how has pain interfered with general activity, % (n)
|
|
|
|
|
0.001
|
|
|
|
0.001
|
Mild: [0, 3]
|
66.3 (4786)
|
61.8 (2454)
|
71.8 (2332)
|
|
66.0 (345)
|
61.7 (177)
|
71.2 (168)
|
|
Moderate: [4, 6]
|
17.5 (1260)
|
21.0 (834)
|
13.1 (426)
|
|
17.0 (89)
|
20.6 (59)
|
12.7 (30)
|
|
Severe: [7, 10]
|
12.1 (872)
|
16.2 (643)
|
7.0 (228)
|
|
12.2 (64)
|
16.4 (47)
|
7.2 (17)
|
|
(Missing)
|
4.2 (300)
|
1.0 (41)
|
8.0 (259)
|
|
4.8 (25)
|
1.4 (4)
|
8.9 (21)
|
|
General health, % (n)
|
|
|
|
|
0.118
|
|
|
|
0.113
|
Excellent
|
8.5 (613)
|
9.9 (394)
|
6.7 (219)
|
|
8.6 (45)
|
10.1 (29)
|
6.8 (16)
|
|
Very Good
|
28.1 (2026)
|
24.7 (980)
|
32.3 (1047)
|
|
28.1 (147)
|
24.7 (71)
|
32.2 (76)
|
|
Good
|
47.1 (3400)
|
49.7 (1974)
|
43.9 (1425)
|
|
46.5 (243)
|
49.5 (142)
|
42.8 (101)
|
|
Fair Poor
|
12.9 (928)
|
14.4 (570)
|
11.0 (357)
|
|
12.6 (66)
|
13.9 (40)
|
11.0 (26)
|
|
(Missing)
|
3.5 (251)
|
1.4 (54)
|
6.1 (197)
|
|
4.2 (22)
|
1.7 (5)
|
7.2 (17)
|
|
PHQ-2 Scorea % (n)
|
|
|
|
|
0.001
|
|
|
|
0.001
|
Less than 3
|
83.5 (6030)
|
86.2 (3425)
|
80.3 (2605)
|
|
82.8 (433)
|
85.7 (246)
|
79.2 (187)
|
|
3 or greater
|
9.8 (704)
|
10.7 (424)
|
8.6 (280)
|
|
9.8 (51)
|
10.8 (31)
|
8.5 (20)
|
|
(Missing)
|
6.7 (483)
|
3.1 (123)
|
11.1 (360)
|
|
7.5 (39)
|
3.5 (10)
|
12.3 (29)
|
|
a Note: PHQ-2 scores of 3 or greater are indicative of the likely presence of a Major Depressive Disorder (and would warrant further clinical assessment) |
The most commonly endorsed reasons for current cannabis use included: sleep disturbance (54.7%, n = 1663), pain (47.1%, n = 1432), mood changes, stress, anxiety or depression (42.6%, n = 1296), and recreation (35.6%, n = 1083; Table 3). Among those who reported using cannabis during or after cancer treatment, the majority did so multiple times per week or more (Table 4). The four most preferred routes of administration endorsed were: eating (i.e., candy, brownies) (44.5%, n = 1355), smoking (34.7%, n = 1056), taking by mouth (e.g., tincture, pills) (32.6%, n = 991), and applying topically (23.7%, n = 720; Fig. 2).
Table 3
Self-Reported Reasons for Cannabis Use
Reasons
|
%a (population weighted n)
|
Difficulty sleeping
|
54.7 (1663)
|
Pain
|
47.1 (1432)
|
Mood changes, stress, anxiety, or depression
|
42.6 (1296)
|
Used recreationally or for enjoyment
|
35.6 (1083)
|
Lack of appetite
|
24.5 (747)
|
Digestive problems (e.g., nausea, vomiting, diarrhea, constipation)
|
23.1 (702)
|
Used as treatment for cancer
|
16.6 (506)
|
Neuropathy (numbness or tingling)
|
16.2 (491)
|
Lack of energy
|
7.8 (237)
|
Sweating symptoms (e.g., hot flashes, night sweats)
|
6.2 (188)
|
Difficulty concentrating
|
5.0 (152)
|
Lack of sexual interest of activity
|
3.5 (107)
|
Skin problems
|
0.9 (28)
|
a Note: participants were informed to “select all that apply” so numbers exceed 100%. |
Table 4
Frequency of cannabis use during and after treatment
During treatment, how often cannabis used (n = 3042)
|
% (population weighted n)
|
Once a month or less
|
17.0 (518)
|
A few times a month
|
10.5 (318)
|
A few times a week
|
22.9 (696)
|
Daily or almost daily
|
29.5 (898)
|
More than once a day
|
19.3 (587)
|
After treatment, how often cannabis used (n = 2339)
|
|
More than once a day
|
13.6 (413)
|
Daily or almost daily
|
24.3 (740)
|
A few times a week
|
21.3 (647)
|
A few times a month
|
13.2 (402)
|
Once a month or less
|
7.7 (236)
|
Only tried it once or twice
|
10.2 (310)
|
Logistic regression analyses were conducted to examine variables significantly associated with cannabis use at anytime since cancer diagnosis. Covariates included in these analyses were age, sex, race/ethnicity, education level completed, household income, occupational status, prior cannabis use, opioid use, and health coverage status. Results indicate that participants with moderate past week average pain severity were more likely to use cannabis (OR = 2.4 [95% CI = 1.3–4.6], p = 0.002). In this model, non-Hispanic ethnicity and prior cannabis use were also associated with an increased likelihood of cannabis use (p < 0.001). A second logistic regression was conducted to examine the extent to which self-rated health status was associated with current cannabis use; this model controlled for the same variables. Results did not identify a relationship between self-reported poor or fair health (versus excellent health) and cannabis use (OR = 0.6 [95% CI = 0.2–1.6], p = 0.316). A final model examined the extent to which depressive symptomatology was associated with cannabis use. After controlling for covariates, depressed mood (as indicated by a score of 3 or greater on the PHQ-2) was not associated with an increased risk of cannabis use (OR = 0.8 [95% CI = 0.4–1.7], p = 0.566, Fig. 3).