Subjects over the age 60 with sustained sitting diastolic pressures of 95-115 mm Hg were randomised to a regime based on bisoprolol (n = 368) or nifedipine retard (n = 379) for 24 weeks. The goal diastolic pressure was < or =90 mm Hg and to achieve this, double-blind medication could be doubled (5/10 mg bisoprolol, 40/80 mg nifedipine retard) or hydrochlorothiazide 25 mg (unblinded) could be added to the higher dose. In an intention-to-treat analysis, 309 subjects in both the bisoprolol and nifedipine retard treated group provided at least a baseline and a second quality of life assessment (82%). An excess of symptoms was observed in the nifedipine group for oedema of the legs, nocturia, constipation, racing heart and heart thumping. Fewer patients reported wheeze in the nifedipine group. For quality of life, there were no statistically significant differences between the two groups after 8 weeks. However, when analysing the results of the last available assessment (usually at 24 weeks) there were significant (P < 0.05) improvements in tension/anxiety, anger/ hostility, vigour/activity, and confusion/bewilderment, assessed by the Profile of Mood States (POMS) in patients receiving bisoprolol in comparison to those receiving nifedipine retard. The Sickness Impact Profile and objective tests of cognitive function did not differ statistically between the two groups. Quality of life was maintained at a good level on both treatments with advantages for bisoprolol in certain areas. Journal of Human Hypertension (2000) 14, 205-212.