Impact of Changes in Regular Use of Marijuana and/or Tobacco On Chronic Bronchitis

Figures & data

TABLE 1.  Number of follow-up participants by smoking category, age, duration of follow-up and smoking history

Smoking Status	N	Age	Years first to last visit	Tobacco			Marijuana
				Baseline pack-years	Cigarettes / Day		Baseline joint-years	Joints / Day
					First Interview	Last Interview		First Interview	Last Interview
UNCHANGED
NS ≡ NS	77	32.2 (0.7)*	10.8 (0.4)	0.0 (0.0)	0.0 (0.0)	0.0 (0.0)	0.0 (0.0)	0.0 (0.0)	0.0 (0.0)
MS ≡ MS	72	31.8 (0.6)	9.4 (0.5)	3.7 (1.2)	0.0 (0.0)	0.0 (0.0)	62.1 (20.4)	4.5 (1.1)	3.0 (0.4)
TS ≡ TS	40	36.9 (1.1)	8.6 (0.6)	21.6 (2.3)	28.7 (2.4)	22.4 (2.7)	0.0 (0.0)	0.0 (0.0)	0.0 (0.0)
MTS ≡ MTS	40	33.4 (1.0)	8.6 (0.7)	16.2 (2.0)	19.9 (2.0)	22.5 (2.4)	41.0 (6.0)	3.5 (0.5)	2.7 (0.8)
CHANGED
MS ≡ NS	23	32.7 (1.2)	10.5 (0.6)	2.8 (1.2)	0.0 (0.0)	0.0 (0.0)	53.2 (14.6)	4.2 (0.8)	0.0 (0.0)
TS ≡ NS	9	37.4 (2.0)	11.8 (0.4)	21.6 (5.0)	29.4 (3.6)	0.0 (0.0)	0.1 (0.0)	0.0 (0.0)	0.0 (0.0)
MTS ≡ NS	9	33.2 (2.0)	8.3 (3.6)	11.2 (2.4)	5.3 (2.8)	0.1 (0.1)	52.5 (19.1)	3.2 (1.2)	0.0 (0.0)
MTS ≡ MS	10	37.0 (2.2)	9.1 (1.4)	15.2 (4.9)	15.6 (5.7)	0.0 (0.0)	42.8 (9.7)	7.2 (4.8)	2.3 (0.5)
MTS ≡ TS	12	33.3 (2.1)	10.4 (0.9)	13.7 (2.1)	17.0 (4.2)	18.3 (5.2)	58.1 (15.2)	2.5 (1.1)	0.0 (0.0)

*Mean (SEM)

Figure 1.  Prevalence of chronic respiratory symptoms in the entire longitudinal cohort (N = 299) by baseline smoking status.

Figure 2.  Prevalence of respiratory symptoms at the baseline visit (A) and the final visit (B) in only those follow-up participants whose smoking status did not change.

TABLE 2.  Odds ratios (OR) and 95% C.I. for having a chronic respiratory symptom (cough, sputum, wheeze, acute bronchitic episodes) at follow-up 
1) for continuing smokers of marijuana or tobacco compared to never smokers, 2) continuing smokers of marijuana or tobacco compared to former smokers (those who quit since baseline) and 3) former smokers of marijuana or tobacco compared to never smokers

		Cough	Sputum	Increased bronchitis episodes	Wheeze
Tobacco
Current vs. Never	OR	3.7	2	3.3	4
	95% C.I.	2.1, 6.6	1.1, 3.6	1.8, 6.2	2.3, 7.1
	p	<.0001	0.0185	0.0002	<.0001
Current vs. Former	OR	2.8	2.8		4.9
	CL	1.2, 6.6	1.05, 7.6		2.4, 10.x
	p	0.0162	0.0405	NS	<.0001
Former vs. Never	OR
	95% C.I.
	p	NS	NS	NS	NS
Marijuana
Current vs. Never	OR	1.7	2.1	2.3	3.4
	95% C.I.	1.01, 2.9	1.1, 4.0	1.2, 4.4	1.7, 6.6
	p	0.0447	0.0201	0.0117	0.0003
Current vs. Former	OR	3.3	4.2		2.1
	95% C.I.	1.3, 8.6	1.6, 11.2		1.04, 4.07
	p	0.0155	0.0039	NS	0.0369
Former vs. Never	OR
	95% C.I.
	p	NS	NS	NS	NS

Table 3.  Changes in chronic respiratory symptoms (lost or gained) in relation to persistent or changing smoking status from baseline to the last follow-up visit

		Symptoms
		Cough		Sputum		Acute Bronchitis		Wheeze
Smoking Status		Lost*	Gained†	Lost*	Gained†	Lost*	Gained†	Lost*	Gained†
Unchanged
NS (N = 77)		0/0 (0)§	5/77 (6.5)	2/3 (66.7)	3/72 (4.2)	1/1 (100)	1/76 (14.3)	3/4 (75)	5/73 (6.8)
MS (N = 72)		10/16 (62.5)	6/54 (11.1)	11/18 (61.1)	7/53 (13.2)	9/11 (81.8)	7/60 (11.7)	14/18 (77.8)	10/53 (19.2)
TS (N = 40)		7/11 (63.6)	5/29 (17.2)	8/11 (72.7)	2/29 (6.9)	3/4 (75)_	2/36 (5.5)	7/13 (53.8)	3/27 (11.1)
MTS (N = 40)		5/11 (45.4)	6/27 (22.2)	6/11 (54.5)	5/27 (18.5)	3/5 (60)	4/34 (11.8)	7/12 (58.3)	8/26 (30.8)
Changed
Baseline	Follow-up
MS	NS (N = 23)	3/4 (75)	0/18 (0)	3/4 (75)	0/18 (0)	2/2 (100)	2/21 (9.5)	3/4 (75)	2/19 (10.5)
TS	NS (N = 9)	4/4 (100)	0/5 (0)	3/3 (100)	0/6 (0)	4/4 (100)	0/5 (0)	2/3 (66.7)	1/6 (16.7)
MTS	NS (N = 9)	3/3 (100)	0/6 (0)	3/3 (100)	0/6 (0)	0/0 (0)	0/9 (0)	1/2 (50)	0/6 (0)
MTS	MS (N = 10)	0/1 (0)	4/9 (44.4)	1/3 (33.3)	2/7 (28.6)	0/1 (0)	0/9 (0)	2/4 (50)	1/5 (20)
MTS	TS (N = 12)	1/1 (100)	3/11 (27.2)	3/3 (100)	2/9 (22.2)	1/1 (100)	3/11 (27.2)	3/6 (50)	1/6 (16.7)

*Lost = the number of subjects who lost the designated symptom at follow-up (numerator) as a proportion of the number who had that symptom at baseline (denominator).

^†Gained = the number of subjects who gained the designated symptom at follow-up (numerator) as as a proportion of the number who had not had that symptom at baseline (denominator)

^§Numbers in parentheses represent percentages.