Rationale & ObjectiveBlood pressure (BP) control is essential for preventing cardiorenal complications in chronic kidney disease (CKD), but most patients fail to reach BP target. We assessed longitudinal patterns of antihypertensive drug prescription and systolic BP (SBP). Study DesignProspective observational cohort study Setting & Population2755 hypertensive patients with CKD stages 3–4, receiving care from a nephrologist, from the French CKD-REIN cohort study ExposurePatient factors, including sociodemographic characteristics, medical history, and laboratory data, and provider factors, including number of primary-care physician and specialist encounters. OutcomesChanges in antihypertensive drug class prescription during follow-up: add-on, or withdrawal. Analytical ApproachHierarchical shared-frailty models to estimate hazard ratios (HR) to deal with clustering at the nephrologist level, and linear mixed models to describe Systolic BP trajectory. ResultsAt baseline, median age was 69, mean eGFR, 33 ml/min/1.73m2; 66% of patients were men, 81% had BP ≥130/80 mmHg and 75% were prescribed ≥2 antihypertensive drugs. During a median 5-year follow-up, the rate of changes of antihypertensive prescription was 50 per 100 person-years, 23 per 100 for add-ons and 25 per 100 for withdrawals. After adjusting for risk factors, Systolic BP, and the number of antihypertensive drugs, poor medication adherence was associated with increased HR for add-on, 1.35 (95% confidence interval, 1.01-1.80), while a shorter education level was associated with increased HR for withdrawal, 1.23 (1.02-1.49) for 9-11 years versus ≥12 years. More frequent nephrologist visits (≥4 versus none) were associated with higher HRs of add-on and withdrawal (1.52; 95% CI 1.06-2.18 and 1.57; 1.12-2.19, respectively), while associations with visit frequency to other physicians varied with their specialty. Mean Systolic BPdecreased by 4 mmHg following drug add-on but tended to rise thereafter. LimitationsLack of information on prescriber, and drug dosing. Conclusions: In patients with CKD and poor BP control, changes in antihypertensive drug prescriptions are common and relate to clinician preferences and patients’ tolerability. Sustainable reduction in Systolic BPafter add-on of a drug class is infrequently achieved.
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