The objective of this study was to evaluate the impact of smoking habits on safety of trandolapril assessed by interrogation and by visual analogue scales (VAS). A total of 3402 hypertensive smokers (> or = 1 cigarette/d for at least 6 months) and non-smokers (no smoking or ceased at least 6 months previously) received trandolapril 2 mg/d for 4 weeks. The safety profile of trandolapril was assessed by both interrogation and by VAS. The VAS completed by the patients at D0 and D28 explored the following symptoms: asthenia, nausea, cough, headaches and dizziness. A significant change in cough VAS was previously defined by an at least 19 mm change. VAS analysis was performed on 2840 patients (1296 smokers and 1544 non-smokers), mean age 59 +/- 12 years. Smokers and non-smokers were significantly different for age 56 +/- 12 years vs. 62 +/- 12 years, sex ratio 74 per cent males vs. 45 per cent, history of hypertension 4.5 +/- 6.1 years vs. 5.3 +/- 6.5 years and cough VAS score at D0 35 +/- 26 mm vs. 20 +/- 21 mm. In the total population, 214 adverse events were reported by 177 patients (5.2 per cent). The most frequent adverse events were a cough (2.1 per cent), bronchitis (0.6 per cent), headaches (0.5 per cent), rhinitis (0.4 per cent), nausea (0.4 per cent) and asthenia (0.3 per cent). Cough was reported by 23 smokers (1.5 per cent) and by 49 (2.6 per cent) non-smokers (p = 0.02). In the VAS population, 151 adverse events were reported by 130 patients, 47 smokers (3.6 per cent) and 83 non-smokers (5.4 per cent, p = 0.03). The difference between the two groups was mainly due to a cough: 15 smokers (1.2 per cent) reported a cough vs. 38 non-smokers (2.5 per cent, p = 0.01) and 77 smokers (5.9 per cent) presented a significant change of cough VAS score vs. 124 non-smokers (8.0 per cent, p = 0.03). In this large scale study, 1.9 per cent of patients treated with trandolapril exhibited a cough. Smokers were less likely to present a cough. Use of VAS confirmed this trend.