Association between leukocyte telomere shortening and exposure to traffic pollution: a cross-sectional study on traffic officers and indoor office workers

Table 3 Telomere length by individual characteristics of indoor office workers (referents) and traffic officers

	Referents (n = 57)					Traffic officers (n = 77)
	n	mean^a	(95% CI)^a	p-value^b	p-value^c	n	mean^a	(95% CI)^a	p-value^b	p-value^c
Age
<30 year	16	1.44	(1.31-1.59)			36	1.22	(1.11-1.33)
30-40 year	19	1.21	(1.09-1.33)			31	1.04	(0.98- 1.11)
>40 year	22	1.14	(1.03-1.26)	0.001	-	10	1.03	(0.91-1.17)	0.01	-
Gender
Male	38	1.24	(1.15-1.34)			47	1.12	(1.04-1.20)
Female	19	1.23	(1.10-1.38)	0.90	0.74	30	1.12	(1.04-1.22)	0.91	0.71
Cigarette smoking
Never smokers	26	1.33	(1.20-1.48)			40	1.16	(1.07-1.26)
Ever smokers	31	1.17	(1.10-1.25)	0.04	0.06	37	1.08	(1.01-1.15)	0.17	0.33
Cigarettes/day^d
1-10 cig./day	9	1.19	(1.03-1.37)			5	1.27	(0.94-1.73)
11-20 cig./day	7	1.20	(1.05-1.38)			16	1.05	(0.96-1.14)
>20 cig./day	7	1.19	(0.96-1.47)	0.99	0.47	7	1.09	(0.98-1.22)	0.22	0.38
Pack-years
0 pack-years	26	1.33	(1.20-1.48)			40	1.15	(1.06-1.25)
0.1-10 pack-years	14	1.19	(1.07-1.32)			22	1.11	(1.00-1.23)
>10 pack-years	17	1.16	(1.05-1.28)	0.05	0.16	15	1.05	(0.97-1.14)	0.18	0.43
Exposure to environmental tobacco smoke^e
No	14	1.27	(1.10-1.46)			24	1.18	(1.06-1.31)
Yes	12	1.40	(1.17-1.68)	0.26	0.39	16	1.12	(0.98-1.30)	0.59	0.31
Alcohol consumption, n(%)^f
Occasional/never	24	1.26	(1.15-1.37)			40	1.20	(1.11-1.28)
Every week	14	1.28	(1.16-1.39)			18	1.15	(0.96-1.35)
Every day	16	1.24	(1.04-1.46)	0.93	0.27	13	1.05	(0.97-1.13)	0.13	0.41

^aStatistical analysis on telomere length were performed on log-transformed data to approximate normal distribution. Geometric means and 95% Confidence Intervals (CIs) are reported
^bp-values from t-test (two-class variables) or regression-based test for trend (variables with three categories) for differences in telomere length by subjects' characteristics
^cAge adjusted p-values from regression-based test for trend for differences in telomere length by subjects characteristics. Age was fitted as a continuous variable in the models.
^dData for current smokers are shown
^eData for never smokers are shown
^fSubject count not add up to the total number of participants due to missing values

ISSN: 1476-069X