To assess the effect of stressful life events (SLE) on the monitoring of patients with essential hypertension. Observational and prospective. Primary care. 236 hypertense patients selected by systematic randomised sampling. Age, sex, marital status, cultural level, kind of family, presence of SLE, social support, blood pressure, severity of hypertension, tobacco consumption, alcohol, presence of diabetes, hypercholesterolaemia, body mass index, compliance with hypertension treatment. RESULTS. Mean age was 63.51 (62.05; 64.96), with 66.1% being women and 33.9% men. 48.7% of the patients referred to some SLE during the follow-up. These reached a mean of 47.65 (33.16; 62.15) life change units (LCU). Patients with high-impact SLE (>150 LCU) had a significant increase of 10.91 mm Hg (0.43; 21.40) in their systolic blood pressure and of 9.48 beats per minute (3.78; 15.19) in their heart rate, after monitoring for possible factors of confusion. We observed a similar trend for diastolic pressure, but this did not reach statistical significance. The presence of SLE has a negative effect on systolic blood pressure in hypertense patients.