42 96
factors
[12,13].
Furthermore,
a
connection
between
ciga-
rette smoking and
the oxidative damage
to endothelial cells
caused
by
superoxide
and
other
reactive
oxygen
species
(ROS)
is
well
established.
The
dynamic
balance
between
oxidative and antioxidative
reactions
is heavily
impaired by
smoking,
and
the
final
result
is
a
net
increase
of
oxidative
stress
that
contributes
to
the
loss
of
cavernosal
integrity
[14].
Numerous
preclinical
studies
showed
the
role
of
specific
compounds
of
cigarette
smoke
in
increasing
superoxide
generation
by
both
endothelial
and
smooth
muscle
cells,
impairing
acetylcholine-induced
relaxation
of
arteries,
increasing
messenger
RNA
expression
of
Table
1
–
Characteristics,
outcomes,
and
covariates
of
studies
assessing
the
risk
of
smoking
for
erectile
dysfunction
Study
Sample
size,
n
Age
range,
yr
Classification
standard
of
smoking
Category
OR
(95%
CI)
Adjustment
for
covariates
Gades
et
al,
2005
[3]1329
40–79
Cigarettes
per
day,
no.
0
1
Age
and
the
occurrence
of
hypertension,
diabetes,
or
coronary
heart
disease
<
20
1.63
(0.72–3.67)
20
1.64
(0.82–3.27)
Austoni
et
al,
2005
[6]16
724
NA
Cigarettes
per
day,
no.
0
1
Age, marital
status,
education,
body mass
index,
alcohol
drinking,
physical
activity,
diabetes,
cardiovascular
disease,
hypercholesterolemia
1–10
1.00
(0.90–1.20)
10
1.40
(1.20–1.50)
Duration
of
smoking,
yr
0
1
<
10
1.2
(0.80–1.60)
10–20
1.6
(1.20–2.00)
>
20
1.6
(1.30–2.00)
Mirone
et
al,
2002
[7]2010
>
19
Cigarettes
per
day,
no.
0
1
Age
and
education
10
1.60
(1.00–2.40
>
10
1.60
(1.10–2.50)
Duration
of
smoking,
yr
0
1
20
1.20
(0.80–1.90)
>
20
1.60
(1.10–2.40)
Millett
et
al,
2006
[8]8367
16–59
Cigarettes
per
day,
no.
0
1
Age,
education,
presence
of
cardiovascular
disease
and
diabetes,
current
alcohol
consumption,
and
employment
20
1.24
(1.01–1.52)
>
20
1.39
(1.05–1.83)
He
et
al,
2007
[9]4763
35–74
Cigarettes
per
day,
no.
0
1
Age,
education,
alcohol
consumption,
physical
inactivity,
diabetes,
hypertension,
overweight,
and
hypercholesterolemia
1–10
1.27
(0.91–1.77)
11–20
1.45
(1.08–1.95)
>
20
1.65
(1.08–2.50)
Chew
et
al,
2009
[10]1580
>
21
Cigarettes
per
day,
no.
0
1
Age,
square
of
age,
and
cardiovascular
disease
1–10
1.30
(0.69–2.44)
11–20
1.69
(0.79–3.64)
>
20
1.57
(0.74–3.34)
Wu
et
al,
2012
[11]2686
20–79
Cigarettes
per
day,
no.
0
1
Age,
alcohol
drinking,
physical
activity,
hypertension,
diabetes,
dyslipidemia,
obesity,
and
education
<
20
1.16
(0.95–1.43)
20
1.18
(0.98–1.43)
Duration
of
smoking,
yr
<
11
1.18
(0.89–1.56)
11–17
0.95
(0.74–1.21)
17–23
1.07
(0.84–1.36)
23
1.60
(1.22–2.09)
Bortolotti
et
al,
2001
[22]9670
20–70
Cigarettes
per
day,
no.
<
15
1
Age,
education,
type
of
diabetes,
and
metabolic
control
15–24
1.20
(1.10–1.40)
25
1.40
(1.30–1.70)
Duration
of
smoking,
yr
<
10
1
10–20
1.40
(1.10–1.90)
>
20
1.70
(1.30–2.30)
CI =
confidence
interval; NA = not
available; OR = odds
ratio.
E U R O P E A N
U R O L O G Y
F O C U S
1
( 2 0 1 5
)
3 9 – 4 6
42