Multi-morbidity and blood pressure trajectories in hypertensive patients: A multiple landmark cohort study

Abstract

Background Our knowledge of how to better manage elevated blood pressure (BP) in the presence of comorbidities is limited, in part due to exclusion or underrepresentation of patients with multiple chronic conditions from major clinical trials. We aimed to investigate the burden and types of comorbidities in patients with hypertension and to assess how such comorbidities and other variables affect BP levels over time. Methods and findings In this multiple landmark cohort study, we used linked electronic health records from the United Kingdom Clinical Practice Research Datalink (CPRD) to compare systolic blood pressure (SBP) levels in 295,487 patients (51% women) aged 61.5 (SD = 13.1) years with first recorded diagnosis of hypertension between 2000 and 2014, by type and numbers of major comorbidities, from at least 5 years before and up to 10 years after hypertension diagnosis. Time-updated multivariable linear regression analyses showed that the presence of more comorbidities was associated with lower SBP during follow-up. In hypertensive patients without comorbidities, mean SBP at diagnosis and at 10 years were 162.3 mm Hg (95% confidence interval [CI] 162.0 to 162.6) and 140.5 mm Hg (95% CI 140.4 to 140.6), respectively; in hypertensive patients with ≥5 comorbidities, these were 157.3 mm Hg (95% CI 156.9 to 157.6) and 136.8 mm Hg (95% 136.4 to 137.3), respectively. This inverse association between numbers of comorbidities and SBP was not specific to particular types of comorbidities, although associations were stronger in those with preexisting cardiovascular disease. Retrospective analysis of recorded SBP showed that the difference in mean SBP 5 years before diagnosis between those without and with ≥5 comorbidities was −9 mm Hg (95% CI −9.7 to −8.3), suggesting that mean recorded SBP already differed according to the presence of comorbidity before baseline. Within 1 year after the diagnosis, SBP substantially declined, but subsequent SBP changes across comorbidity status were modest, with no evidence of a more rapid decline in those with more or specific types of comorbidities. We identified factors, such as prescriptions of antihypertensive drugs and frequency of healthcare visits, that can explain SBP differences according to numbers or types of comorbidities, but these factors only partly explained the recorded SBP differences. Nevertheless, some limitations have to be considered including the possibility that diagnosis of some conditions may not have been recorded, varying degrees of missing data inherent in analytical datasets extracted from routine health records, and greater measurement errors in clinical measurements taken in routine practices than those taken in well-controlled clinical study settings. Conclusions BP levels at which patients were diagnosed with hypertension varied substantially according to the presence of comorbidities and were lowest in patients with multi-morbidity. Our findings suggest that this early selection bias of hypertension diagnosis at different BP levels was a key determinant of long-term differences in BP by comorbidity status. The lack of a more rapid decline in SBP in those with multi-morbidity provides some reassurance for BP treatment in these high-risk individuals.

Quality of Care for Patients with Hypertension in selected Health Centres in Rwamagana District, Rwanda

“…Our study findings are consistent with Danish and UK studies which showed a positive association between comorbidity and hypertension control. [30,35,36] Patients with comorbidity may have higher risk perceptions of cardiovascular diseases compared to those without comorbidity. [37,38] These patients may be motivated to engage in healthy behaviours and comply with management regimens that are essential for controlling their hypertension than their counterparts without comorbidity.…”

Sodium-based paracetamol: impact on blood pressure, cardiovascular events, and all-cause mortality

“…Fourth, SBP recordings are often known to be susceptible to measurement error; however, as suggested by previous research, summary measures using averaging are a validated method of alleviating distorted conclusions due to measurement error issues. 15 , 16 Fifth, more precise time-to-event modelling of the outcome and patient censoring are necessary for association analyses. However, because survival DL modelling has not been appropriately developed for association estimation, nuanced evaluation of risk with time-to-event DL modelling should be explored in future studies.…”

Associations between long-term blood pressure trajectory and all-cause and CVD mortality among old people in China

“…Potential confounders were identified based on existing literature rather than deferring to statistical criteria ( 23 , 24 ). We assessed demographic characteristics, socio-economic status, lifestyle behavior change, and health status ( 25 , 26 ), which were reported from face-to-face interviews during each follow-up survey. Demographic characteristics and socio-economic variables included sex (male/female), ethnicity (Han nationality/others), average household income (<5,000/5,000–19,999/>20,000 yuan), place of residence (city/town/rural), main occupation before retired (professional and technical personnel governmental/institutional or managerial personnel/agriculture, forest, animal husbandry/fishery worker/industrial worker/ commercial or service worker/military personnel/housework/others), marriage status (currently married and living with spouse/separated/divorced/widowed/never married).…”