Effect of smoking on lung function, respiratory symptoms and respiratory diseases amongst HIV-positive subjects: a cross-sectional study

Table 3 ORs and 95% CIs of each variable versus respiratory symptoms, respiratory diseases and subject classification

	Cough^a	Sputum^b	Any respiratory symptom^c	Normal lung function without symptom^d
Former smoker	0.8 (0.3, 2.6)	1.7 (0.5, 5.3)	1.0 (0.3, 2.8)	0.9 (0.3, 2.5)
Current smoker	4.3 (1.5, 12.0)**	5.0 (1.9, 13.3) **	4.9 (2.0, 11.8) ***	0.3 (0.1, 0.6) **
Former marijuana user	0.7 (0.3, 2.1)	0.6 (0.2, 1.7)	-	-
Current marijuana user	1.5 (0.5, 4.6)	1.3 (0.5, 3.5)	-	-
White	1.1 (0.4, 3.5)	-	-	-
On HAART	5.5 (1.4, 21.5)*	-	2.7 (0.9, 8.1)	-
Undetectable viral load	0.3 (0.1, 0.9)*	-	-	-

All the results were from multiple logistic regression analysis. Non-smoker group was the reference group in all the analysis. Reference group for other variables was non-marijuana user, non-white subject, subject who was not on HAART and subject who had detectable viral load respectively.
- The variable had p > 0.2 in uni-variate analysis and was not selected into multiple logistic regression analysis.
*p < 0.05 for the OR. ** p < 0.01 for the OR. *** p < 0.001 for the OR.
^a Subject having no cough was reference group. Nagelkerke R² = 0.252.
^bSubject having no sputum was reference group. Nagelkerke R² = 0.177.
^cSubject having no respiratory symptom at all was reference group. Respiratory symptom was defined as cough, sputum or breathlessness. Nagelkerke R² = 0.194.
^d Subject having either abnormal lung function or any respiratory symptom was reference group. Abnormal lung function was defined as either FEV₁/FVC < 70% or %FEV₁<80% or %FVC < 80%, either pre- or post-salbutamol test. Nagelkerke R² = 0.128.

ISSN: 1742-6405