Nine hundred and twenty-two hypertensive patients were included in a substudy to the hypertension optimal (HOT) study which aimed to investigate the impact on quality of life of lowering the pressure and of intensified therapy. Patients were randomised to three diastolic BPs (DBPs) levels, i.e. less than or equal to 90 mmHg, less than or equal to 85 mmHg and less than or equal to 80 mmHg. Seven hundred and eighty one patients completed both baseline and follow-up questionnaires after 6 months (intention to treat, ITT population),while 610 patients were included in a per protocol (PP) analysis. The lower the DBP achieved, the greater the improvement in well-being (p < 0.05). The increase in well-being from baseline to 6 months was significant in target groups less than or equal to 80 mmHg (p<0.01) and less than or equal to 85 mmHg (p<0.05). Cardiac symptoms and dizziness improved in all groups but the sex life score deteriorated in the less than or equal to 80 and less than or equal to 85 mmHg groups in male patients. Headachezs were reduced in all groups (p<0.001), while swollen ankles (p<0.001), and dry cough in the less than or equal to 80 mmHg group (p<0.001) increased. Despite a slight increase in subjective symptoms, more intensive antihypertensive therapy was still associated with improvements in patients' well-being.