Page 166 - HIVMED_v21_i1.indb

Page 4 of 8 Original Research

120 Never smoker Former smoker Current smoker a 120 Never smoker Former smoker Current smoker b
100 100
23 21 19 29 80 26 21
80
Propor on (%) 60 15 13 16 15 Propor on (%) 60 19 13

40
62 66 65 56 40 55 66
20 20

0 0
< = 34 35–44 45–54 > = 55 Men Women
Age groups in years (p = 0.649) Gender (p = 0.022)

120 Never smoker Former smoker Current smoker c 120 Never smoker Former smoker Current smoker d
100 100
23 21 80 22 22
80
Propor on (%) 60 17 12 Propor on (%) 60 10 17

40
60 67 40 68 61
20 20

0 0
< 5 years > = 5 years < 396/mm 3 > = 396/mm 3
Diagnosed dura on of HIV (p = 0.040) CD4 count (p = 0.151)

CD4, cluster of differentiation 4; HIV, human immunodeficiency virus.
FIGURE 1: Smoking status in different subgroups defined by (a) age, (b) gender, (c) known duration of human immunodeficiency virus infection and (d) cluster of
differentiation 4 count.

by age category (p = 0.649). Smoking status was also Figure 3 shows the cross-classification of smoking exposure
marginally related to the known duration of HIV infection by self-reports and serum cotinine levels, revealing the lack
(p = 0.040) but not the CD4 count (p = 0.151) (Figure 1). of agreement between the two classification methods
(kappa = -0.014, p = 0.488). Among the 751 participants with
Exposure to second-hand smoke was high with significantly data available on serum cotinine levels, 158 (21.0%) were
higher rates in women (58.8%) compared with men (44.8%) current smokers based on self-reports, 108 (14.4%) were
(p = 0.001) (Table 1). The use of smokeless tobacco products former smokers, and 485 (64.6%) had never smoked. Among
was low, at < 3% for any sub-category, with no significant current smokers based on self-reports, 95 (60.1%) had cotinine
differences by gender or smoking status. levels lower than 10 ng/mL, indicative of low tobacco
exposure, while 45 (28.5%) had cotinine levels above
The median duration of diagnosed HIV infection was 6 100 ng/mL, indicative of moderate-to-heavy smoking.
years in current smokers, 5 years in non-smokers and 4 Among those who had never smoked, 300 (61.9%) had no
years in former smokers (p = 0.020). There were no significant exposure to tobacco based on cotinine levels, while 112
differences in the median CD4 counts by smoking status. In (23.1%) had cotinine levels compatible with moderate-to-
age- and gender-adjusted logistic regression models, none heavy smoking (Figure 3).
of the general and HIV-predictive characteristics was
associated with current smoking (Table 2). Discussion
Our data show that over one in five PLWHA currently smoke
Data on serum cotinine were available for 751 participants. tobacco, with men being more likely to do so than women
About a quarter of these participants had serum cotinine and with no indication that smoking habits were influenced
levels > 100 mg/mL, indicating exposure to tobacco smoke. either by the duration or by the time since HIV diagnosis and
Prevalence of high serum cotinine levels was similar across awareness of the nadir CD4 count. Furthermore, over half of
smoking status (current smokers: 28.5%, former smokers: the study samples (including those who had never smoked)
25.9% and never smokers: 23.1%) (p = 0.564) and did not were exposed to second-hand smoke, with such exposure
differ between men and women (p = 0.940), between those being higher in women. For participants with data
above and below median duration of diagnosed HIV available on serum cotinine concentrations, about a quarter
infection (p = 0.681) and between those above and below (including among self-declared never-smokers) had cotinine
median CD4 count (p = 0.505) (Figure 2). concentrations indicative of moderate-to-heavy tobacco

http://www.sajhivmed.org.za 158 Open Access