Effect of felodipine in hypertensive patients with mild cerebral insufficiency in a randomised double-blind study

Background and objective: Cognitive impairment occurs more frequently in hy pertensives than in normotensive individuals. Early signs of cognitive Impa irment are predictors of dementia in late life. Felodipine is capable of al most normalizing plasma viscosity, which is elevated in most of hypertensiv e patients, thus improving microcirculation. The aim of this study was to e valuate whether this haemorheologic property of felodipine in addition to i ts blood pressure lowering effect can improve cognitive performance in hype rtensive patients. Patients and methods: Randomized, double-blind comparison between felodipin e 10 mg and hydrochlorothiazide 50 mg amiloride 5 mg (HCT/amiloride) in pat ients 50-70 years of age with impaired cognitive function (c.l. test 1-2 po ints) and with resting blood pressure values of diastolic > 95 and less tha n or equal to 115 mmHg and/or systolic > 160 and less than or equal to 210 mmHg. Blood pressure measurements and evaluation of total short term storag e capacity were done at the beginning and after 12 weeks of treatment. Results: 31 patients (14 felodipine and 17 HCT/amiloride) were included in the per protocol analysis. Blood pressure values at the beginning and after 12 weeks of treatment were (mmHg): for felodipine systolic 168 +/- 4 and 1 50 +/- 6 (p < 0.01), diastolic 108 +/- 3 and 88 +/- 4 (p < 0.001). For amil oride/HCT systolic 173 +/- 8 and 150 +/- 10 (p < 0.01), diastolic 105 +/- 5 and 88 +/- 5 (p < 0.001). Short term storage capacity improved by 15 +/- 6 bits during felodipine treatment (p < 0.001) and by 9 +/- 9 bits during am iloride/HCT treatment (p < 0.05). Thus cognitive improvement was superior b y 67% in the felodipine group compared to amiloride/HCT (p<0.05). Conclusion: In this study a pronounced improvement of mental performance oc curred in patients treated with felodipine. Since the cognitive gain was si gnificantly superior to amiloride/HCT treatment there must be an additional blood pressure-independent effect of felodipine, such as enhancing microci rculation. Whether these properties possibly counteract the development of dementia in hypertensives has to be evaluated in long term studies in more patients.