Prevalence and clinical profile of resistant hypertension among treated hypertensive subjects

Detecting Risk Of Postural hypotension (DROP): derivation and validation of a prediction score for primary care

OBJECTIVES

Falls are a common problem in older people. Postural hypotension contributes to falls but is often asymptomatic. In the absence of symptoms, postural hypotension is only infrequently checked for in clinical practice. We undertook this study to derive, validate and explore the prospective associations of a prediction tool to identify people likely to have unrecognised postural hypotension.

DESIGN AND SETTING

Cross-sectional and prospective multivariable cohort analysis.

PARTICIPANTS

1317 participants of the Invecchiare in Chianti study, a population-based cohort representative of the older Italian population.

PRIMARY OUTCOME MEASURES

Predictive value of score to suggest presence of postural hypotension.

METHODS

Subjects were randomised 1:1 to derivation or validation cohorts. Within the derivation cohort, univariable associations for candidate predictors of postural hypotension were tested. Variables with p<0.1 entered multivariable linear regression models. Factors retaining multivariable significance were incorporated into unweighted and weighted Detecting Risk Of Postural hypotension (DROP) scores. These scores were tested in the validation cohort against prediction of postural hypotension, cognitive decline and mortality over 9 years of follow-up.

RESULTS

Postural hypotension was present in 203 (15.4%) of participants. Factors predicting postural hypotension were: digoxin use, Parkinson's disease, hypertension, stroke or cardiovascular disease and an interarm systolic blood pressure difference. Area under the curve was consistent at 0.65 for all models, with significant ORs of 1.8 to 2.4 per unit increase in score for predicting postural hypotension. For a DROP score ≥1, five cases need to be tested to identify one with postural hypotension.Increasing DROP scores predicted mortality (OR 1.8 to 2.8 per unit rise) and increasing rates of decline of Mini Mental State Examination score (analysis of variance p<0.001) over 9 years of follow-up.

CONCLUSIONS

The DROP score provides a simple method to identify people likely to have postural hypotension and increased risks to health who require further evaluation.

Prevalence and characteristics of resistant hypertensive patients in an Asian population

BACKGROUND

Resistant hypertension is a well-recognized clinical challenge yet there are no reported data on its prevalence in Pakistan. These patients are subjected to a higher risk of developing hypertensive complications. The objective of our study was to evaluate the prevalence and determinants of resistant hypertension in an Asian cohort of hypertensive patients.

METHODS

This cross-sectional study was carried out among hypertensive patients visiting a tertiary care hospital in Karachi from September-December 2015. Patient data and characteristics were recorded using a pre-coded questionnaire. Morisky and Berlin questionnaires were used to assess compliance to medications and determine the risk of developing obstructive sleep apnea, respectively. Pearson's chi-square test was used to analyze statistical differences between hypertensive patients and related factors.

RESULTS

A total of 515 patients were included in the study. Overall, 12% of the total patients (n=62) were resistant hypertensives and 25% (n=129) had pseudo-resistant hypertension. Resistant patients were more often females, older and had a higher body mass index (all P<0.001). Use of painkillers and noncompliance to dietary recommendations were found to be significant determinants of resistant hypertension. Prevalence of comorbid conditions, including diabetes (p=0.33), hyperlipidemia (p=0.46), and chronic kidney disease (p=0.23), was not significantly higher in patients with resistant hypertension.

CONCLUSION

Nearly one in ten hypertensive patients had true resistant hypertension, and twenty-five percent of patients had pseudo-resistance. Resistance hypertensions is significantly associated with female gender, older age, obesity, dietary noncompliance and increased use of NSAIDs.

Is home blood pressure monitoring useful in the management of patients with resistant hypertension?

BACKGROUND

Ambulatory blood pressure (BP) monitoring (ABPM) is a cornerstone in resistant hypertension (RHT) management. However, it has higher cost and lower patients' acceptance than home BP monitoring (HBPM). Our objective was to evaluate HBPM usefulness in the management of patients with RHT.

METHODS

A total of 240 patients were submitted to 24-hour ABPM and 5-day HBPM (triplicate morning and evening measurements). Patients with uncontrolled office BP (≥140/90mm Hg) were classified as true RHT (daytime or home BP ≥135/85mm Hg) or white-coat RHT (daytime or home BP <135/85mm Hg), and patients with controlled office BP were classified as masked RHT (daytime or home BP ≥135/85mm Hg) or controlled RHT (daytime or home BP <135/85mm Hg). Sensitivity, specificity, predictive values, and likelihood ratios for HBPM were calculated. Agreement between the procedures was evaluated using kappa coefficients and the Bland-Altman method.

RESULTS

Mean office BP was 157±26/84±16mm Hg, mean daytime BP was 134±18/77±13mm Hg, and mean home BP was 143±20/76±14mm Hg. The ABPM and HBPM diagnoses were 35% and 48%, respectively, for true RHT; 36% and 23%, respectively, for white-coat RHT; 7% and 17%, respectively, for masked RHT; and 22% and 13%, respectively, for controlled RHT. HBPM overestimated systolic BP by 8.8 (95% confidence interval (CI) = 6.8-10.7) mm Hg and diastolic BP by 0.2 (95% CI = -1.0 to 1.4) mm Hg. The specificity, sensitivity, and positive and negative predictive values of HBPM in detecting controlled ambulatory BP were 91%, 55%, 89%, and 59%.

CONCLUSIONS

HBPM presented good agreement with ABPM and can be used as a complementary method in the follow-up of resistant hypertensive patients, particularly in those with controlled ambulatory BPs.

Characteristics, drug combinations and dosages of primary care patients with uncontrolled ambulatory blood pressure and high medication adherence

Most studies on the prevalence and determinants of resistant hypertension (RH) do not account for white coat hypertension, medication non-adherence, or use of suboptimal treatment dosages. We studied the characteristics, drug combinations, and dosages of patients on at least three antihypertensives of different classes who had uncontrolled blood pressure on 24-hour ambulatory blood pressure monitoring and high medication adherence measured by electronic monitoring. The data were collected as part of the baseline measures of a hypertension control trial. Of 140 monitored primary care patients, all with uncontrolled office blood pressure, 69 (49%) were on at least three antihypertensives of different classes. Of these 69, 15 (22%) were controlled on ambulatory blood pressure monitoring, 20 (29%) were uncontrolled and non-adherent, leaving only 34 (49%) adherent to their medications and having uncontrolled ambulatory hypertension (uncontrolled RH). Thirty-one (91%) of the 34 uncontrolled RH patients were prescribed a diuretic, of which 24 were on hydrochlorothiazide 25 mg. Less than half of the patients on angiotensin-converting enzyme inhibitor, angiotensin receptor blocker, or calcium channel blocker were prescribed maximal doses of these agents. Half of the RH can be attributed to white coat effect and poor medication adherence, and all of the remaining patients were on apparently suboptimal drug combinations and/or dosages. Primary care physicians need to be educated regarding the optimal treatment of RH.