Excess stroke among hypertensive men and women attributable to undertreatment of hypertension

Background and Purpose-Most population-based studies indicate that a consid erable proportion of hypertensive subjects are undertreated and that undert reatment is more prevalent among hypertensive men than among hypertensive w omen. The aim of our study was to investigate the consequences of undertrea tment of hypertension for women and men in terms of stroke occurrence. Methods-Approximately 45 000 men and women aged greater than or equal to 20 years were examined in 2 population-based studies in the Netherlands. A co hort of 2616 hypertensive subjects (pharmacologically treated hypertensives and untreated hypertensives who needed pharmacological treatment according to the severity of their hypertension and the coexistence of additional ca rdiovascular risk factors) was selected for a follow-up study. Follow-up (m ean duration, 4.6 years) was complete for 2369 (91%) of the enrolled hypert ensive subjects. Results-Compared with treated and controlled hypertensives, the relative ri sks of stroke for treated and uncontrolled hypertensives and for untreated hypertensives who needed treatment were 1.30 (95% CI, 0.70 to 2.44) and 1.7 6 (95% CI, 1.05 to 2.94), respectively. These relative risks and the preval ence of (undertreated) hypertension in the total population of 45 000 subje cts were used to estimate the number of strokes in the Netherlands attribut able to undertreatment. Among hypertensive men and women aged greater than or equal to 20 years in the Netherlands, the proportions of strokes attribu table to treated but uncontrolled blood pressure were 3.1% (95% CI, -5.2% t o 18.7%) and 4.1% (95% CI, -7.2% to 20.7%), respectively. For untreated hyp ertensive men and women who should have been treated, these proportions wer e 22.8% (95% CI, 0.8% to 38.4%) and 25.4% (95% CI, 0.5% to 42.5%), respecti vely. Conclusions-Increasing the detection of hypertension and improving adherenc e to current guidelines might prevent a considerable proportion of the inci dent strokes among hypertensives. The potential impact of achieving control of blued pressure in patients already being treated on the reduction of st rokes requires further investigation.