Background Arterial stiffness is defined as the loss of compliance of the elastic arteries in the human body and is associated to ageing. Hypertension is the leading global risk factor for cardiovascular disease and is related to a higher frequency of cardiovascular events. A high proportion of the hypertensive population is not aware of their condition or is not provided with adequate blood pressure treatment. The aim of this work is to assess the 4-year rate of change in arterial stiffness according to antihypertensive treatment at baseline in a population of British civil servants and to estimate the differences in the risk of major cardiovascular events between the different categories of change.

Methods Carotid-femoral Pulse Wave Velocity (cf-PWV) is the gold-standard to assess arterial stiffness and it was measured both at baseline (Phase 9, 2008–9) and follow-up (Phase 11, 2011–12) in 4998 participants of the cohort (3680 men; 1318 women). It was measured using the Sphygmacor ® Atcor tonometric device. Major cardiovascular events were defined as myocardial infarction, stroke and coronary heart disease. The information about these outcomes was extracted from the NHS Hospital Episode Statistics. 5-year change models were fitted using linear mixed model regression.

Results There were 1842 (36.9%) controlled hypertensive, 871 (17.4%) untreated hypertensive and 557 (11.1%) uncontrolled hypertensive participants in the total sample. A model adjusted for sociodemographic characteristics, comorbidities and health behaviours showed that compared to non-hypertensives, mean PWV increase was 0.04 m/s (95%CI: -0.04,0.17 p:0.51) for controlled hypertensives, 0.20 m/s (95%CI: 0.06,0.35 p<0.001) untreated hypertensives and 0.25 (95%CI: 0.03,0.47 p<0.05) for uncontrolled hypertensives. The risk of major adverse cardiovascular events was almost four times in uncontrolled hypertensive participants (HR: 3.72; 95%CI 2.47–5.59) and three times in controlled hypertensives (HR: 2.48; 95%CI 1.92–3.21) compared to normotensive participants. A significant difference was not found in untreated hypertensive participants.

Conclusion The rate of arterial stiffening over time and the risk of major adverse cardiovascular effects is higher in uncontrolled participants of the Whitehall II study, compared with normotensive participants. This is additional evidence of the need for improved strategies for blood pressure control in hypertensive patients.