PULSE PRESSURE DYNAMICS: UNRAVELING THE IMPACT ON TARGET ORGAN DAMAGE, INDEPENDENT OF MEAN ARTERIAL PRESSURE

Abstract

Objective: As individuals age, pulse pressure (PP) naturally increases due to arteriosclerosis and diffuse vascular stiffening. In the absence of an identifiable cause, a wide PP signals target organ damage (TOD) and adverse clinical outcomes. While hypertension is endemic in South Asia, there is paucity of data regarding determinants of PP and relationship with TOD in this region. We therefore aimed to explore the determinants of PP in an ambulatory patient population. Design and method: We analysed electronic medical records of subjects (n=8,362, 64% females 64%) attending a Medicine outpatient Department (OPD) at Shalamar Hospital, a tertiary care hospital, in Lahore, Pakistan during the period September 1st, 2021 to September 30th, 2023. Haemodynamic data included single measure of systolic and diastolic BP and heart rate. HTN was defined according to ESH and ACC guidelines. History of CVD included ishaemic heart disease and stroke. Relationshp between variables was analysed using univariate and multivariate analysis. Pp was analysed both as a continuous and categorical variable (>50, mm Hg). Results: Of the 8,362 subjects attending the OPD, 62% and 100% had a diagnosis of HTN as per ESH and ACC guidelines, respectively. PP>50, mm Hg was present in 56% and 45% of HTN as defined by ESH and ACC respectively. PP>50, mm Hg was associated with age (OR=2.7), female gender (OR=1.46), chronic kidney disease (CKD, OR= 3.6), CVD (OR=1.47) and diabetes mellitus (DM, OR=1.54). In a stepwise regression model, age, gender, heart rate, DM, CKD and CVD were associated with PP, independent of mean arterial pressure (R2=0.45, p<0.0001). Conclusions: To the best of our knowledge, this is the first large study, exploring the determinants of PP in Pakistan. While the study is retrospective, using single office BP measurements, it highlights the importance of PP as an independent predictor of TOD. Prospective studies are the need of the hour to elucidate the pathophysiology and outcome of high PP in this population.