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Few studies describe clinical outcomes of hypertension phenotypes in unselected
cohorts including those who never achieve controlled BP and few separately
describe renal outcomes. A recent retrospective study used electronic health records
in a large, ethnically diverse population to evaluate and compare the risk of renal,
cardiovascular, and mortality outcomes among individuals with controlled resistant
hypertension (cRH), uncontrolled resistant hypertension (uRH), and nonresistant
hypertension (non-RH) [ 20 ]. Data were derived using office BP among 470,386
individuals enrolled to a prepaid integrated health plan in the USA, of which 60,327
(12.8%) were identified as having aTRH. With the exception of sleep apnea, indi-
viduals with diagnosed secondary causes of hypertension were excluded. Definition
of aTRH was office BP ≥140/90 mmHg with three different antihypertensive medi-
cations or needing four or more antihypertensive medications irrespective of
BP. There was no ABPM available and pseudoresistance was partly excluded by
assessing medication adherence from pharmacy dispensation data. A subset of
patients intolerant of diuretics were included in the aTRH cohort; however, 97% of
the aTRH population were using a diuretic. When compared to the non-RH group,
the aTRH group had greater prevalence of diabetes (48% vs 30%), CKD defined as
eGFR <60 mL/min/1.73 m^2 (45% vs 24%), ischemic heart disease (41% vs 22%),
and cerebrovascular disease (16% vs 9%). There was no significant difference in
comorbidities between controlled and uncontrolled aTRH groups. A total of 114,364
events occurred comprising all-cause death, ischemic heart disease events, conges-
tive heart failure, stroke, and incident end-stage renal disease. Both unadjusted and
adjusted event rates were greater in the aTRH group for all measured outcomes.
Uncontrolled aTRH was associated with a greater stroke risk (HR, 1.23; 95% CI,
1.14–1.31) and greater end-stage renal disease risk (HR, 1.25; 95% CI, 1.18–1.33).
This study concluded that compared to non-RH, aTRH had greater risks of incident
ischemic heart disease, heart failure, stroke, and end-stage renal disease. Among
those with aTRH, there was a further increased risk of stroke and end-stage renal
disease for uncontrolled versus controlled BP.
Clinical Outcomes in Observational Studies
of CKD Populations
A retrospective Italian study evaluated the burden of RH in 300 patients referred for
management of CKD stages 2 to 5 [ 15 ]. Staging of CKD used Kidney Disease:
Improving Global Outcomes (KDIGO) guidelines [ 25 ] and eGFR was calculated by
serum creatinine in the 4-variable Modified Diet in Renal Disease equation [ 26 ].
Home BP or ABPM were used to exclude pseudoresistance by white coat hyperten-
sion. Adherence to medication and dietary salt restriction were assessed by ques-
tionnaire, pill counts, and 24-h urinary sodium. True RH was diagnosed as office BP
≥130/80 mmHg despite three antihypertensive drugs at optimal dose including a
diuretic, or as controlled BP using four or more drugs. Five hundred and fifty
patients were screened, and 250 were excluded for pseudoresistance due to white
A. Odudu et al.