Effects of Cigarette Smoking on Rate of Loss of Pulmonary Function in Adults: A Longitudinal Assessment

Abstract

Data from a random sample of 8,191 men and women selected in six U.S. cities and examined on three occasions over a 6-yr follow-up period were analyzed by longitudinal methods to describe the effects of smoking history and current smoking behavior on rate of loss of pulmonary function during adult life. Former smokers had age- and height-adjusted rates of decline (34.3 ml/yr for men and 29.6 ml/yr for women) comparable with those of never smokers (37.8 ml/yr for men and 29.0 ml/yr for women) but much smaller than those of continuing smokers (52.9 ml/yr for men and 38.0 ml/yr for women). The accelerated rate of loss of FEV1 among smokers depended linearly on the number of cigarettes smoked per day during the interval between examinations. The estimated increase in rate of loss associated with smoking was 12.6 ml/yr per pack/day for men and 7.2 ml/yr per pack/day for women. These longitudinal estimates of the effects of smoking were approximately 50% larger than estimates obtained from cross-sectional analysis of the initial pulmonary function examination. Men who started smoking had accelerated rates of loss (55.9 ml/yr) as did women (43.1 ml/yr). Smokers who stopped smoking between examinations had reduced declines (41.2 ml/yr for men and 28.7 ml/yr for women) compared with continuing smokers. The age-specific rates of loss suggest that the benefits of cessation may be greatest among the youngest smokers.(ABSTRACT TRUNCATED AT 250 WORDS)

Longitudinal Change in FEV1 and FVC in Chronic Spinal Cord Injury

“…As in able-bodied persons, continued smoking was associated with a greater loss of FEV 1 and FVC compared with neversmokers, and the rate of decline was similar to that of ablebodied individuals (26). In our previous cross-sectional analysis, we demonstrated with each pack-year smoked a decrease in FEV 1 of similar magnitude to our current study (4).…”

Forced vital capacity in two large outpatient populations with chronic spinal cord injury

“…From ®ndings by Dockery et al 18 we would project a four percentage-point mean FVC decrement in able-bodied people resembling our 45 years-and-older paraplegics who ever smoked in terms of their mean age, current smoking prevalence, and available pack-year data; whereas our subjects' observed decrement was seven percentage points. Although di erences between current and former smokers were not clear in the present analyses, the earlier separate NY and LA studies, 8,9 as well as numerous studies of able-bodied populations, 10,18,19 attest to long-term lung function bene®ts from stopping smoking.…”

“…Most studies of smoking e ects in able-bodied populations have focused on airway obstruction (ie, FEV 1 ) rather than FVC, but FVC losses have been observed cross-sectionally 17,18 and longitudinally. 19 Current information, though not de®nitive, is consistent with the possibility that losses are larger in SCI than in able-bodied populations. From ®ndings by Dockery et al 18 we would project a four percentage-point mean FVC decrement in able-bodied people resembling our 45 years-and-older paraplegics who ever smoked in terms of their mean age, current smoking prevalence, and available pack-year data; whereas our subjects' observed decrement was seven percentage points.…”

Sex differences in lung vulnerability to tobacco smoking

“…But, other cross-sectional studies, such as the Beijing respiratory health study [2], a Canadian study [14], the French Cooperative study [8], the Tucson Airways study [15] and both a cross-sectional and longitudinal study from Copenhagen [4,16] have reported a greater decline in lung function among females than males, associated with tobacco smoking. On the other hand, opposite results have been found in both cross-sectional and longitudinal studies, such as the Six Cities study [17], the Tucson Airways Study [18], the cross-sectional part of the Netherlands study [13], the Copenhagen study (after redefining exclusion criteria, but not adjusting for quantity smoked) [19], an Italian study [20] and the UCLA study from Los Angeles [21]. Comparisons between crosssectional and longitudinal studies are distorted, as those with better lung function are more likely to continue in longitudinal studies [13].…”