Lifestyle-related risk factors, smoking status and cardiovascular disease

Cardiovascular disease represents one of the most important causes of morbidity and mortality in highly developed countries and is known to be associated with some lifestyle-related risk factors (e.g. alcohol consumption, smoking status, diet, physical activity, bodyweight). There is still incomplete information about their combined effect on cardiovascular risk in hypertensive patients with optimal pharmacological blood pressure control.

The objective of this study was to evaluate the correlation of some lifestyle behaviours, using a specific questionnaire, with development of cardiovascular disease in treated hypertensive patients.

617 hypertensive, non-diabetic participants (aged 53.1 ± 7.6 years, 44.9% male; mean age 53.1 ± 7.6 years) free of prevalent cardiovascular disease, cancer, liver cirrhosis and/or failure, chronic kidney disease more than grade 3 (glomerular filtration rate by the Modification of Diet in Renal Disease study <30 mL/min/1.73 m2) were analysed. Metabolic syndrome was defined according to the Third Report of the Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). Left ventricular hypertrophy was defined when left ventricular mass index was >51 g/m2. Carotid artery atherosclerosis was assessed as an increased intima medial thickness (IMT) by B-mode ultrasonography. IMT values between 0.9 and 1.3 mm were defined as 'thickening' and those >1.3 mm as 'plaque'. Assessment of smoking status, dietary and non-dietary factors was established by administration of a specific questionnaire.

In the initial population of examined patients, 288 were smokers and 329 were non-smokers. At baseline, the patients belonging to smoking group were less often overweight than those belonging to the non-smoking group, showing a lower initial body mass index (BMI) [27.54 ± 4.0 vs 28.28 ± 4.3; p < 0.029], lower plasma levels of high-density lipoprotein cholesterol (HDL-C) [48.14 ± 12.6 vs 51.39 ± 14.1 mg/dL; p < 0.006] and were more often affected by carotid artery atherosclerosis (93.9 % vs 86.1%; p < 0.002) than non-smoking patients. When analysed for dietary and other lifestyle-related risk factors, we found a higher prevalence of carotid atherosclerotic disease in patients consuming less than two meals per day than in those consuming more than two meals per day (96.6% vs 85.7%; p < 0.001), without any significant difference in the mean number of medications taken and in specific classes of medications. Total amount of cigarettes smoked, calculated as packs per year (39.14 ± 16.5 vs 20.81 ± 13.6; p < 0.0001) was higher in patients with a diagnosis of atherosclerotic disease of the carotid artery than in patients free of this disorder, whereas the average age at which people began smoking was lower (17.58 ± 6.3 vs 21.53 ± 10.2 years). In a binary model of logistic regression adjusted for BMI, HDL-C, smoking status and number of daily meals, only smoking status was confirmed to be strongly correlated to clinical evidence of carotid atherosclerosis (p < 0.025).

In hypertensive patients, in optimal blood pressure control, smoking status has been shown to be independently associated with an increased maximum arterial IMT (IMTmax). In particular, an increase of the IMT was associated with the total amount of cigarettes smoked (calculated as packs per year) and the average age at which people began smoking.