Purpose and method: A hospital based case-control study was designed to investigate what aspects of smoking and what co-factors of smoking are associated with the development of peripheral arterial disease (PAD). Cases were 291 smokers, newly referred with PAD, and controls were 828 age and sex matched smokers without PAD.
Results: Reported recent tobacco usage was similar in cases and controls but total tobacco exposure was associated with the risk of PAD-adjusted odds ratios (ORs) increasing with tertile of pack-years smoked to reach 1.63 (95% CI, 1.11-2.39; P = 0.011), for the highest tertile ( > 48 pack-years) compared with smokers in the lowest tertile (< 31 pack-years). Cases reported smoking significantly lower tar and nicotine yield cigarettes than controls, but tended to inhale more deeply, and had significantly higher plasma concentrations of cotinine. ORs for PAD were significantly and independently increased by systolic blood pressure > 160 mmHg (8.1 (5.2 13.0); P < 0.0001), history of hypertension (2.4 (1.5-3.2); P = 0.0003) and apolipoprotein B > 0.9 g/l(3.8 (2.3-7.6); P = 0.008).
Conclusions: Increased total exposure to tobacco and the ability to smoke tobacco in a way which maximises nicotine yield are associated with increased risk of smokers developing PAD. There is no evidence that smoking low tar cigarettes reduces this risk, whereas both hypertension (particularly systolic) and high levels of apolipoprotein B, increase this risk.