Associations of Cigarette Smoking With Subclinical Inflammation and Atherosclerosis: ELSA‐Brasil (The Brazilian Longitudinal Study of Adult Health)

Abstract

BackgroundThere is a need to identify sensitive biomarkers of early tobacco‐related cardiovascular disease. We examined the association of smoking status, burden, time since quitting, and intensity, with markers of inflammation and subclinical atherosclerosis.Methods and ResultsWe studied 14 103 participants without clinical cardiovascular disease in ELSA‐Brasil (Brazilian Longitudinal Study of Adult Health). We evaluated baseline cross‐sectional associations between smoking parameters and inflammation (high‐sensitivity C‐reactive protein [hsCRP]) and measures of subclinical atherosclerosis (carotid intima–media thickness, ankle‐brachial index, and coronary artery calcium [CAC]). The cohort included 1844 current smokers, 4121 former smokers, and 8138 never smokers. Mean age was 51.7±8.9 years; 44.8% were male. After multivariable adjustment, compared with never smokers, current smokers had significantly higher levels of hsCRP (β=0.24, 0.19–0.29 mg/L; P<0.001) and carotid intima–media thickness (β=0.03, 0.02–0.04 mm; P<0.001) and odds of ankle‐brachial index ≤1.0 (odds ratio: 2.52; 95% confidence interval, 2.06–3.08; P<0.001) and CAC >0 (odds ratio: 1.83; 95% confidence interval, 1.46–2.30; P<0.001). Among former and current smokers, pack‐years of smoking (burden) were significantly associated with hsCRP (P<0.001 and P=0.006, respectively) and CAC (P<0.001 and P=0.002, respectively). Among former smokers, hsCRP and carotid intima–media thickness levels and odds of ankle‐brachial index ≤1.0 and CAC >0 were lower with increasing time since quitting (P<0.01). Among current smokers, number of cigarettes per day (intensity) was positively associated with hsCRP (P<0.001) and CAC >0 (P=0.03) after adjusting for duration of smoking.ConclusionsStrong associations were observed between smoking status, burden, and intensity with inflammation (hsCRP) and subclinical atherosclerosis (carotid intima–media thickness, ankle‐brachial index, CAC). These markers of early cardiovascular disease injury may be used for the further study and regulation of traditional and novel tobacco products.

Carotid intima-media thickness in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil): a narrative review

“…Table 1 [12][13][14][15][16][17][18][19][20] shows the main aims, findings and conclusions of articles focusing on the association with traditional risk factors and Table 2 21-32 shows the main aims, findings and conclusions of articles focusing on the association with novel cardiovascular risk factors or other conditions.…”

Lifestyle and biological factors influence the relationship between mental health and low-grade inflammation

“…Similarly, even mental wellbeing as measured in our paper has been associated with lower odds of smoking initiation and higher odds of successful smoking cessation 60 . Again, smoking has been previously associated with the circulating levels of inflammatory markers, both in cross-sectional 61,62 and in longitudinal studies 63 In this study, we modelled the relation between subclinical inflammation and mental status hypothesizing that the latter could influence the former. Although there is contrasting evidence on the directionality of this relationship [41][42][43][77][78][79] , one of these studies supported a bi-directional effect between mental health and inflammation 79 .…”

Unprocessed red meat intakes are associated with increased inflammation, triglycerides and HDL cholesterol in past smokers

“…55 Finally, it seems a bit unexpected that unprocessed red meat does not increase CRP and triglycerides or decrease HDL cholesterol in current smokers; however, it is not surprising that unprocessed red meat may make modest contributions to inflammation and disturbed lipid levels when compared to cigarette smoking in current smokers. Cigarette smoking can significantly increase circulating inflammation 18,56 and triglycerides and reduce HDL cholesterol. 21,57 Our results demonstrated that smoking status is an effect modifier.…”