PAVM persistence occurred in more than a third of smokers with more than 20 pack years
, compared with 12.2% of nonsmokers.
were calculated for both cigarette and huqqa smokers with the following formulas:
Some studies have shown that hearing loss increases with increase in pack years
while other studies have found that the so-called "dose effect" changes with age.
The amount of cigarettes you smoke is measured in pack years
. A pack year
is 20 cigarettes a day for one year.
Demographic Profile of the Patients All Non- Patients Smokers Smokers P (n = 200) (n = 100) (n = 100) value Age 41.1 [+ or -] 43.3 [+ or -] 39.6 [+ or -] 0.23 11.6 11.7 11.2 ASA status I 128 58 70 0.10 II 72 42 30 Procedure Upper 112 62 50 0.65 Abdomen 88 45 43 Lower Abdomen Pack Years
18.3 [+ or -] 0 >0.01 10.4 Table 2.
Subjects were eligible for the study if they were: aged [greater than or equal to]40 years; current or former smokers (history [greater than or equal to]20 pack years
); and had no history of asthma or any other lung diseases.
A study by Ali Ahmed, M.D., M.P.H., senior researcher and professor of cardiovascular disease at the University of Alabama at Birmingham's School of Medicine, showed that older people who smoked less than 32 "pack years
"- 3.2 packs (20 cigarettes per pack) a day for no more than 10 years or less than one pack a day for 30 years - and gave up smoking 15 or fewer years ago lowered their risks of developing heart failure or dying from heart failure, heart attacks and strokes to the same level as those who had never smoked.
Last year, for instance, the National Comprehensive Cancer Network (NCCN) recommended that people 50 (not 55) or older who have at least 20 (not 30) pack years
of smoking plus one additional risk factor, such as having chronic obstructive pulmonary disorder or a close relative with lung cancer, also be screened.
Number of pack years
= (number of cigarettes per day/20) x number of years smoked.
The guidelines, released in May, recommend yearly CT scans for people age 55-74 who have smoked for 30 pack years
or more (e.g, one pack a day for 30 years or two packs a day for 15 years) or who have quit within the past 15 years.
were calculated by multiplying number of packs per day with the years of smoking.
Group I (5 to 9 pack years
) and group II (= 10 pack years