HYPERTENSION BURDEN AND BLOOD PRESSURE CONTROL IN A TERTIARY CARDIO-ONCOLOGY SERVICE

Abstract

Background Hypertension among oncology patients is linked to increased risk of acute cardiotoxicity events and adverse long-term cardiovascular outcomes. Blood pressure control in this cohort presents unique challenges, given the interplay of disease pathophysiology and cancer therapies. This study describes hypertension burden and blood pressure control in a large outpatient cardio-oncology cohort. Methods We performed a retrospective review of a random subset of patients presenting to outpatient cardio-oncology clinic in a large tertiary centre in London, United Kingdom, from an extract of all patients accessing the service between November 2016 to January 2024. Patients without an oncological diagnosis were excluded. Patient demographics (age, sex, ethnicity), underlying primary malignancy, and baseline morbidity profile were defined from electronic health records at the first in-person clinic visit. Hypertension diagnosis and prescribed antihypertensive medications were defined from electronic hospital or linked primary care records at time of the first clinical consultation. Blood pressure was calculated as the mean of the last three clinic measurements taken on separate days. Elevated blood pressure was defined as an average systolic reading above 140mmHg and/or mean diastolic reading greater than 90mmHg. Ambulatory blood pressure testing was extracted from clinical results. Continuous variables are presented as mean (standard deviation) and count variables as number (percentage). Results A total of 566 patients median age 64.5 years, 51% males] were evaluated (table 1). The most common malignancies were breast cancer (n=134/566, 24%), colorectal cancer (n=66/566, 12%), and leukemia (n=56/566, 10%). Metastatic disease was present in one-fifth (n=114/566) of patients. Diabetes was recorded in 23% (n=129/566) of patients, coronary artery disease in 19% (n=109/566), and atrial fibrillation in 18% (n=100/566). Diagnosed hypertension was identified in over 40% of patients (n=236/566). Those with diagnosed hypertension were more likely to be male (59%, n=140/236), had higher body mass index, and higher rate of cardiometabolic conditions than those without hypertension. Among those with hypertension, 45% (n=106/236) had suboptimal blood pressure control, 10% (n=23/236) were not on any antihypertensive medications, while 29% (n=68/ 236) were on one, 39% (n=92/236) on two, 19% (n=45/ 236) on three, and 3% (n=8/236) on four different antihypertensive classes. Among the total population, 27% (n=153/566) had elevated average blood pressure measurements, of these 31% (n=47/152) did not have diagnosed hypertension. Ambulatory blood pressure monitoring was performed in 21 patients, of whom three had no pre-existing diagnosis of hypertension, while the remainder had a known diagnosis. Conclusion Hypertension is common and often suboptimally managed in oncology patients. Blood pressure control in oncology patients should be prioritised to alleviate the shortand long-term burden of cardiovascular disease in this cohort.