Background

Public statements about the effect of smoking on cardiovascular disease are predominantly based on investigations of coronary heart disease (CHD) and stroke, although smoking is recognized as a strong risk factor for peripheral artery disease (PAD). No study has comprehensively compared the long-term association of cigarette smoking and its cessation with the incidence of 3 major atherosclerotic diseases (PAD, CHD, and stroke).

Objectives

The aim of this study was to quantify the long-term association of cigarette smoking and its cessation with the incidence of the 3 outcomes.

Methods

A total of 13,355 participants aged 45 to 64 years in the ARIC (Atherosclerosis Risk In Communities) study without PAD, CHD, or stroke at baseline (1987 to 1989) were included. The associations of smoking parameters (pack-years, duration, intensity, and cessation) with incident PAD were quantified and contrasted with CHD and stroke using Cox models.

Results

Over a median follow-up of 26 years, there were 492 PAD cases, 1,798 CHD cases, and 1,106 stroke cases. A dose-response relationship was identified between pack-years of smoking and 3 outcomes, with the strongest results for PAD. The pattern was consistent when investigating duration and intensity separately. A longer period of smoking cessation was consistently related to lower risk of PAD, CHD, and stroke, but a significantly elevated risk persisted up to 30 years following smoking cessation for PAD and up to 20 years for CHD.

Conclusions

All smoking measures showed significant associations with 3 major atherosclerotic diseases, with the strongest effect size for incident PAD. The risk due to smoking lasted up to 30 years for PAD and 20 years for CHD. Our results further highlight the importance of smoking prevention and early smoking cessation, and indicate the need for public statements to take PAD into account when acknowledging the impact of smoking on overall cardiovascular health.

Background and aims

The ankle-brachial index (ABI) is a diagnostic test for screening and detecting peripheral artery disease (PAD), as well as a risk enhancer in the AHA/ACC guidelines on the primary prevention of atherosclerotic cardiovascular disease (ASCVD). However, our understanding of the association between ABI and cardiovascular risk in contemporary older populations is limited. Additionally, the prognostic value of ABI among individuals with prior ASCVD is not well understood.

Methods

Among 5,003 older adults at ARIC visit 5 (2011-2013) (4,160 without prior ASCVD [median age 74 years, 38% male], and 843 with ASCVD [median age 76 years, 65% male]), we quantified the association between ABI and the risk of heart failure (HF), and composite coronary heart disease and stroke (CHD/stroke) using multivariable Cox regression models.

Results

Over a median follow-up of 5.5 years, we observed 400 CHD/stroke events and 338 HF cases (242 and 199 cases in those without prior ASCVD, respectively). In participants without a history of ASCVD, a low ABI ≤0.9 (relative to ABI 1.11-1.20) was associated with both CHD/stroke and HF (adjusted hazard ratios 2.40 [95% CI: 1.55-3.71] and 2.23 [1.40-3.56], respectively). In those with prior ASCVD, low ABI was not significantly associated with CHD/stroke, but was with HF (7.12 [2.47-20.50]). The ABI categories of 0.9-1.2 and > 1.3 were also independently associated with increased HF risk. Beyond traditional risk factors, ABI significantly improved the risk discrimination of CHD/stroke in those without ASCVD and HF, regardless of baseline ASCVD.

Conclusions

Low ABI was associated with CHD/stroke in those without prior ASCVD and higher risk of HF regardless of baseline ASCVD status. These results support ABI as a risk enhancer for guiding primary cardiovascular prevention and suggest its potential value in HF risk assessment for older adults.

Background and aims

Peripheral artery disease (PAD) and lower levels of physical activity are both associated with higher mortality. Yet, their joint prognostic impact has not been systematically examined, especially in Hispanics/Latinos, and with objective measures. We aimed to examine the joint associations of PAD and physical activity with mortality in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL).

Methods

We studied 7,620 Hispanic/Latino adults aged 45-74 years at baseline (2008-2011) who underwent assessment of PAD with ankle-brachial index (ABI) and physical activity with hip-worn accelerometry. We calculated four physical activity measures: sedentary time, light activity, moderate/vigorous activity, and total activity counts. We quantified the relationship between ABI and mortality overall, and by tertiles of activity measures in restricted cubic splines, using multivariable Cox models accounting for sampling weights. We also assessed cross-categories of ABI and activity measures with mortality.

Results

During a median follow up of 7.1 years, 314 participants died. We observed a U-shaped association of ABI with mortality overall (e.g., hazard ratio 1.80 [95%CI 1.20-2.80] at ABI 0.7 vs 1.2). This U-shaped association was generally consistent after stratifying by activity measures, but an elevated mortality risk for higher ABI was not evident in the most active tertile based on sedentary time, time in light activity, and total activity counts. In the cross-category analysis of ABI and physical activity, the highest mortality risk was consistently seen in abnormal ABI (≤0.9 or >1.4) plus the least active tertile (e.g., HR 5.61 [3.31-9.51] for light activity), compared to referent ABI (0.9-1.4) plus the other more active two tertiles, with no interactions between ABI and activity measure.

Conclusions

Abnormal ABI and lower accelerometry-based physical activity were independently and jointly associated with mortality in Hispanics, suggesting the importance of simultaneously evaluating leg vascular condition and physical activity.