Cigarette use is a known risk factor for the development of coronary artery disease (CAD) as it adversely affects HDL cholesterol levels and promotes thrombogenesis. Smoking may also be associated with behavioral characteristics that potentiate the risk of CAD. A lack of cholesterol knowledge would indicate an aversion to a prevention-oriented lifestyle. Thus, our goal was to determine the association between tobacco use and knowledge of self-reported cholesterol among male physicians. Using the 1982 and follow-up questionnaires from the physician health study, we report the changes in the frequencies of awareness of self-reported total cholesterol and cardiovascular risk factors among the 22,067 participants. We classified physicians as being aware of their cholesterol if they reported a cholesterol level and unaware if the question was left unanswered. In 1997, 207 physicians were excluded, as the recorded cholesterol was not interpretable, leaving 21,860 for our follow up analyses. Using unadjusted logistic models, we determined the odds ratios (OR) and 95% confidence intervals (CI) of not reporting a cholesterol level in either 1982 or 1997 for each specified risk factor. We then evaluated whether the lack of cholesterol awareness at both time points was associated with the use of tobacco throughout the study. After 14-years of follow up, cholesterol awareness increased from 35.9 to 58.6 percent. During this period, the frequency of hypertension and hyperlipidemia treatment increased (13.5 to 40.5% and 0.57% to 19.6% respectively), as did the diagnosis of diabetes (2.40 to 7.79%). Behavioral characteristics such as a sedentary lifestyle and obesity also increased (27.8 to 42% and 43.5 to 53.5%, respectively), however the proportion of current smokers deceased from 11.1 to 4.05%. The percentages of individuals being unaware of their cholesterol decreased in all risk factor groups. However, individuals were likely to be unaware of their cholesterol at both time points if they were current smokers (1982 OR 1.44, CI 1.4-1.7; 1997 OR 1.71, CI 1.48-1.97), past smokers (1982 OR 1.12, CI 1.05-1.18; 1997 OR 1.13, CI 1.06-1.20), overweight (BMI 25 kg/m2) or sedentary. In addition, physicians who never quit smoking were likely to be unaware of their cholesterol throughout the study (OR 1.42, CI 1.21-1.67). Cholesterol awareness in general and among those with CAD risk factors improved after 14-years of follow-up. However, the likelihood of being unaware was greater among smokers at both time points. Therefore, smokers do not appear to take advantage of other preventive strategies that would minimize their risk of developing CAD.
Keywords: Disease prevention; cholesterol; lifestyle behavior; tobacco smoking.