The forced vital capacity (FVC) entered many symptom and disease models with a positive coefficient (odds ratio above 1.0), acting to correct the FEVi for body size. We preferred to enter the FEVi, FVC, height, weight, age, gender, and race variables separately into each model instead of entering the FEVi/FVC ratio or the percent predicted FEVi as indices of airways obstruction. For comparison with other studies, when we did enter the FEVi/FVC percent into each model (instead of the above variables separately), we obtained the following (significant) odds ratios for an incremental decrease of 10 percent: for chronic cough, 1.31; for chronic phlegm, 1.24; and for emphysema, 1.98.
Chronic cough and chronic phlegm were more likely in those with a low FEVi, and in those currently smoking. Chronic phlegm production was reported more frequently in men, those with coronary heart disease, and was positively associated with pack-years of smoking. allergy treatment
About 10 percent of CHS participants answered “yes” to the question “Do you ever have to stop for breath when walking at your own pace on the level?” (grade 3 dyspnea on exertion [DOE]). Our model of predictors of this symptom is consistent with the notion that dyspnea is a nonspecific symptom with multiple causes. Those with congestive heart failure (CHF) or coronary heart disease or emphysema were three to four times as likely to report this degree of dyspnea as participants without these diseases. The prevalence of CHF was 3 percent in men and 2 percent in women. Chronic bronchitis, asthma, advanced age, a low FEVi (or a low vital capacity), a large waist or hip size, pack-years of smoking, and lower education were also independently associated with DOE. Although the overall prevalence of DOE was higher in never-smoking women than never-smoking men (Table 1), there was no significant gender effect in this multivariate model.