Cigarette smoke is a risk factor for severity and treatment outcome in patients with culture-positive tuberculosis

Figures & data

Table 1 Demographic characteristics of subjects with negative (n=114) and positive (n=245) cultures from 2010 to 2012

	Negative cultures, n (%)	Positive cultures, n (%)
Sex
Female	39 (34)	70 (29)
Male	75 (66)	175 (71)
Age, years
Mean ± SD	57±18	59±21
Range	20–96	16–94
BMI, kg/m^2
Mean ± SD	22±4	22±4
Range	13–40	12–33
Marital status^a
Unmarried	16 (14)	42 (17)
Married	98 (86)	203 (83)
Smoking status
Nonsmokers	66 (58)	146 (60)
Current smokers	17 (15)	32 (13)
Former smokers	31 (27)	67 (27)
Alcohol consumption
No	78 (68)	179 (73)
Yes	36 (32)	66 (27)
Education
Less than high school	61 (53)	129 (53)
High school or equivalent	27 (24)	77 (31)
More than high school	26 (23)	39 (16)
Socioeconomic status
High	3 (2)	2 (1)
Middle	93 (82)	204 (83)
Low	18 (16)	38 (16)
HIV infection
Yes	0	0
No	114 (100)	245 (100)
Pulmonary cavity
Yes	0	63 (26)
No	114 (100)	182 (74)
CXR grading
Mean ± SD	–	33±29
Range	–	3–140
Sputum positive to negative, days
Mean ± SD	–	242±108
Range	–	32–773
Treatment outcome
Alive	–	212 (87)
Dead	–	33 (13)

Note: –, data not available.

Abbreviations: SD, standard deviation; BMI, body mass index; CXR, chest X-ray.

Figure 1 Smoking and the success rate of treating tuberculosis and CXR grading.

Notes: (A) Proportion of success rate of treating tuberculosis (TB) in patients with positive cultures who were nonsmokers, former smokers, and current smokers (No, treatment failure; Yes, treatment success). (B) Chest X-ray (CXR) grading of patients with TB-positive cultures who were nonsmokers, former smokers, and current smokers. *P<0.05.

Table 2 Estimated ORs (95% CI) of the risk for tuberculosis patients with positive cultures among former smokers and current smokers

Smoking status	OR (95% CI)a
Nonsmokers	1
Former smokers	1.00 (0.71–1.89)
Current smokers	1.36 (1.03–2.36)*

Notes:

a Adjusted for age, sex, and BMI;

* P<0.05.

Abbreviations: ORs, odds ratios; CI, confidence interval; BMI, body mass index.

Table 3 Hazard ratios of sputum-culture conversion duration (days) in subjects with tuberculosis-positive cultures

Smoking status	Sputum-culture conversion, hazard ratio (95% confidence interval)a
Never-smokers	1
Former smokers	0.83 (0.58–1.17)
Current smokers	1.12 (1.03–1.39)*

Notes:

a Adjusted for age, sex and body mass index;

* P<0.05.