Clinical guidelines for the treatment of hypertension in African Americans

Treatment retention on fingolimod compared with injectable multiple sclerosis therapies in African-American patients: A subgroup analysis of a randomized phase 4 study

BACKGROUND

Suboptimal persistence with injectable disease-modifying therapies (iDMTs; interferon beta-1a/b, glatiramer acetate) is common in patients with relapsing forms of multiple sclerosis (MS), reducing the effectiveness of these agents. Adherence to, and persistence with, an effective therapy is important for patient populations at increased risk of rapid disease progression. African-American individuals with multiple sclerosis may experience a more aggressive disease course than Caucasian patients, with a greater risk of developing ambulatory difficulties and other disabilities, and may also have a diminished response to some disease-modifying therapies compared with patients of other ethnicities. Retention on oral fingolimod and on iDMTs was evaluated in a post hoc analysis of data from African-American patients in the parallel-group, 48-week 'Prospective, Randomized, active-controlled, open-label study to Evaluate patient retention on Fingolimod versus approved first-line disease modifying thErapies in adults with Relapsing-remitting Multiple Sclerosis' (PREFERMS).

METHODS

In PREFERMS, patients with relapsing-remitting MS aged 18-65 years with an Expanded Disability Status Scale score ≤6 enrolled at 117 US study sites were treatment-naïve or had received only one iDMT class. Patients were randomized 1:1 (fingolimod 0.5 mg/day:preselected iDMT) using an interactive voice-and-web-response system without blinding, followed up quarterly, and allowed one study-approved treatment switch after 12 weeks, or earlier, for efficacy or safety reasons only. The primary outcome was patient retention on randomized treatment over 48 weeks. In this post hoc analysis of African-American patients in PREFERMS, outcome variables included rate of patient retention on randomized treatment, reasons for discontinuing randomized treatment, patient-reported treatment satisfaction, and safety. Clinical and radiographic outcomes such as annualized relapse rate, brain volume loss, and lesion count changes were also investigated.

RESULTS

In PREFERMS, 141 of 875 patients (16.1%) randomized to a study drug were African-American. Analysis of data for the full analysis set of 67 patients receiving fingolimod and 69 receiving iDMTs showed that the retention rate over 48 weeks was significantly higher with fingolimod than with iDMTs (80.6% [n = 54] vs 30.4% [n = 21]; between-group difference: 50.2%; 95% confidence interval 35.8-64.6%; p < 0.0001). The most common treatment switch was from an iDMT to fingolimod for injection-related reasons, and patient satisfaction was greater with fingolimod than with iDMTs. Adverse events were consistent with the respective prescribing information for each treatment.

CONCLUSION

In PREFERMS, fingolimod was associated with better treatment retention than iDMTs in African-American patients. Optimal outcomes in the management of multiple sclerosis depend on good persistence with treatment, and this is particularly important in patient populations at increased risk of a rapidly progressing disease course.

Evaluation of living kidney donors: variables that affect donation

Approximately 10000 deceased donor organs are available yearly for 85 000 US patients awaiting kidney transplant. Living kidney donation is essential to close this gap and offers better survival rates. However, nationally, 80% of potential donors evaluated fail to donate. Nurse coordinators who perform predonation screening and education need additional insight into the large number of potential donors who fail to complete the donation process. Reasons for nondonation in donor candidates undergoing medical evaluation, and variables affecting nondonation at Vanderbilt University Medical Center between 2004 and 2009 are examined. Multivariable logistic regression models are used to test the effects of age and race on donation status and reasons for nondonation. Summary data are frequencies, percentages, and means (SD). The sample included 706 candidates (63% female, 80% white; mean age, 40 [SD, 12] years). Almost half (46%) received clearance to donate. Undiagnosed hypertension (14%), abnormal glucose tolerance (10%), and protein-urea (9%) were the most prevalent medical reasons for nondonation. About 13% of candidates changed their minds during evaluation. Analyses demonstrated an increased likelihood of older candidates (P < .001) and a decreased likelihood of white candidates (P = .007) being excluded from donation. Within the nondonation group, increased age was associated with undiagnosed hypertension and abnormal glucose tolerance (both race-adjusted, P = .01). Younger candidates (race-adjusted, P = .003) and African Americans (age-adjusted, P = .04) were more likely to decide against donation. The most prevalent medical reasons for nondonation could be identified through enhanced prescreening, and improved preevaluation education could decrease nondonation rates.

Ethnic differences in the effects of the DASH diet on nocturnal blood pressure dipping in individuals with high blood pressure

BACKGROUND

Ethnic differences in nocturnal blood pressure (BP) dipping may contribute to the increased risk for adverse cardiovascular events noted in African Americans (AAs). The DASH (Dietary Approaches to Stop Hypertension) diet has been shown to be efficacious in lowering clinic and ambulatory BP; however, the effect of the DASH diet on BP dipping is unclear.

METHODS

One hundred and eighteen men and women with high clinic BP (systolic BP (SBP) 130-159; diastolic BP 85-99) and above ideal body weight were randomized to a DASH diet intervention or to a usual diet control (UC) condition. Measures of 24-h ambulatory BP were obtained at baseline and at the end of the 4-month intervention period.

RESULTS

At baseline, AAs (n = 43) displayed blunted nocturnal SBP dipping compared to Caucasians (CAs; n = 75) and were more likely to be categorized as nondippers (<10% nocturnal decline in SBP, AAs: 51% vs. CAs: 27%). AAs randomized to the DASH diet intervention showed a significant improvement in SBP dipping postintervention compared to AAs in the UC condition (P = 0.04), whereas there was no appreciable change in SBP dipping in CAs (P = 0.72). Following the intervention, ethnic differences in SBP dipping were no longer statistically significant (nondipper status: AAs: 44% vs. CAs: 32%; P = 0.19).

CONCLUSIONS

Our study provides preliminary evidence suggesting that in overweight men and women with high BP, AAs may be especially likely to benefit from augmented SBP dipping associated with consumption of the DASH diet.

An evaluation of the efficacy of olmesartan medoxomil in Black patients with hypertension

Blacks appear to have a more modest blood pressure (BP) response to angiotensin receptor blocker (ARB) monotherapy than non-Blacks. This post-hoc analysis compared the BP-lowering efficacy of olmesartan medoxomil (OM), losartan potassium (LOS), and valsartan (VAL) in Black versus non-Black participants in a randomized, forced-titration study. Patients were randomized to OM 20, LOS 50, and VAL 80mg/day or placebo for 4 weeks and uptitrated to 40, 100, and 320mg/day doses, respectively, by study end. The primary end point was the mean change from baseline in diastolic BP (DBP) at week 8. All treatments produced significant reductions in mean DBP and systolic BP (SBP) in Blacks (n=150; P < .001). BP <140/90mm Hg was achieved in 35.0%, 15.6%, 29.7%, and 5.0% of Blacks receiving OM, LOS, VAL, and placebo, respectively, and in 41.0%, 21.1%, 28.8%, and 14.5% of non-Blacks receiving OM, LOS, VAL, and placebo, respectively, after 8 weeks. BP-lowering efficacy of the three agents was similar at 3 months. OM had the greatest early efficacy, with numerically greater mean reductions in DBP and SBP, and a higher proportion of Black and non-Black patients achieving goal BP of 140/90mm Hg at week 8.

Correlates of support for living donation among African American adults

CONTEXT

Living donation is studied with much less intensity among African Americans than among the general population. Examination of barriers to living donation can lead to effective strategies to educate dialysis patients and their families about this alternative.

OBJECTIVE

To explore the correlates of likelihood of becoming a living donor among community-recruited African American adults.

DESIGN/PARTICIPANTS

Cross-sectional data were gathered via self-administered questionnaire from 425 African American adults, age 18 years and older, who were recruited from 9 churches in Atlanta.

MAIN OUTCOME MEASURES

Self-reported likelihood of becoming a living donor to a close family member, an extended family member or friend, or a stranger.

RESULTS

More than three-quarters of participants were willing to act as living donors to a close family member or spouse and two-thirds to friends or extended family. For likelihood of donating to a friend or extended family member, only willingness to engage in deceased donation was significantly associated; to a stranger, both willingness to engage in deceased donation and attitudes toward donation were significantly associated. Knowledge of and personal experiences with donation and/or transplantation were not significantly associated with likelihood of any type of living donation.

CONCLUSIONS

Findings indicate widespread support for living donation to a close family member or spouse. These findings have important implications for dialysis patients who must decide whether to approach friends and/or family about the possibility of serving as a living donor and emphasize the need for interventions to help facilitate this process.

Correlates of Support for Living Donation among African American Adults

Context

Living donation is studied with much less intensity among African Americans than among the general population. Examination of barriers to living donation can lead to effective strategies to educate dialysis patients and their families about this alternative.

Objective

To explore the correlates of likelihood of becoming a living donor among community-recruited African American adults.

Design/Participants

Cross-sectional data were gathered via self-administered questionnaire from 425 African American adults, age 18 years and older, who were recruited from 9 churches in Atlanta.

Main Outcome Measures

Self-reported likelihood of becoming a living donor to a close family member, an extended family member or friend, or a stranger.

Results

More than three-quarters of participants were willing to act as living donors to a close family member or spouse and two-thirds to friends or extended family. For likelihood of donating to a friend or extended family member, only willingness to engage in deceased donation was significantly associated; to a stranger, both willingness to engage in deceased donation and attitudes toward donation were significantly associated. Knowledge of and personal experiences with donation and/or transplantation were not significantly associated with likelihood of any type of living donation.

Conclusions

Findings indicate widespread support for living donation to a close family member or spouse. These findings have important implications for dialysis patients who must decide whether to approach friends and/or family about the possibility of serving as a living donor and emphasize the need for interventions to help facilitate this process.

Endothelial dysfunction in African-Americans

The journey of atherosclerosis begins with endothelial dysfunction and culminates into its most fearful destination producing ischemia, myocardial infarction and death. The excess cardiovascular disease morbidity and mortality in African-Americans is one of the major public health problems. In this review, we discuss vascular endothelial dysfunction as a key element for excess cardiovascular disease burden in this target population. It can be logical window of future atherosclerotic outcomes, and further efforts should be made to detect it at the earliest in African American individuals even if they are appearing healthy as the therapeutic interventions if instituted early, might prevent the subsequent cardiac events.

Efficacy and safety of fixed combinations of irbesartan/hydrochlorothiazide in hypertensive women: the inclusive trial

OBJECTIVE

This post hoc analysis of the Irbesartan/Hydrochlorothiazide Blood Pressure Reductions in Diverse Patient Populations (INCLUSIVE) trial evaluated the efficacy and safety of irbesartan/hydrochlorothiazide (HCTZ) in a diverse population of hypertensive women.

METHODS

INCLUSIVE was a multicenter, prospective, open-label, single-arm trial. Adult subjects had uncontrolled systolic blood pressure (SBP 140-159 mm Hg; 130-159 mm Hg for those with type 2 diabetes mellitus [T2DM]) after > or =4 weeks of antihypertensive monotherapy. Treatment was sequential: placebo (4-5 weeks), HCTZ 12.5 mg (2 weeks), irbesartan/HCTZ 150/12.5 mg (8 weeks), and irbesartan/HCTZ 300/25 mg (8 weeks). Mean changes from baseline to treatment end in SBP and diastolic blood pressure (DBP), BP goal attainment, and safety were assessed.

RESULTS

Treatment with irbesartan/HCTZ was associated with significant mean reductions in BP (intent-to-treat population, n = 370; SBP/DBP: -22.9/-10.3 +/- 14.7/8.8 mm Hg). Improvements in SBP were observed in all subgroups (p < 0.001): Caucasian (n = 207) -23.5 +/- 13.5 mm Hg; African American (n = 93) -21.0 +/- 17.2 mm Hg; Hispanics/Latino (n = 66) -23.6 +/- 14.3 mm Hg; age <65 years (n = 281) -22.5 +/- 14.7 mm Hg; age > or =65 years (n = 89) -24.3 +/- 14.5 mm Hg; T2DM (n = 97) -19.0 +/- 15.1 mm Hg; and metabolic syndrome (n = 187) -22.1 +/- 14.6 mm Hg. Overall, 82% (95% confidence interval [CI] 78%-86%) of women achieved their SBP goal, 86% (95% CI 83%-90%) achieved their DBP goal, and 76% (95% CI 71%-80%) achieved their dual SBP/DBP goal. Treatments were well tolerated in all groups.

CONCLUSIONS

Irbesartan/HCTZ treatment was effective and well tolerated in a diverse population of women whose BP was previously uncontrolled on monotherapy.

Contribution of dairy products to dietary potassium intake in the United States population

OBJECTIVE

Adequate dietary potassium intake is associated with a reduced risk of cardiovascular and other chronic diseases. The Dietary Guidelines for Americans 2005 identifies milk and milk products as a major contributor of dietary potassium and lists dairy products, along with fruits and vegetables, as food groups to encourage. This paper further examines the impact of dairy consumption on the potassium intake of the United States (US) population.

METHODS

Using data from the National Health and Nutrition Examination Survey (NHANES) 1999-2002 we determined potassium intakes for various age groups of individuals who met the recommended number of dairy servings compared to those who did not. We also examined the impact of dairy servings consumed on mean and median potassium intakes and compared intakes to the age-appropriate Adequate Intakes (AI).

RESULTS

For all age groups, mean and median potassium intakes did not meet the respective AI. Mean potassium intakes were significantly greater in those subjects who met dairy intake recommendations compared to those who did not for all age groups. Mean and median potassium intakes increased with increasing dairy intake but were below current intake recommendations for all age groups analyzed. For adults age 19 to 50, 16.1% consumed the recommended number of dairy servings per day. For those 51 and older, 10.7% met current dairy intake recommendations.

CONCLUSIONS

Consumption of dairy products is below current recommendations which contributes in part to suboptimal dietary potassium intakes among a large proportion of the US population. Since adequate potassium intake is associated with decreased risk of chronic disease, consumption of a variety of potassium-rich foods, including fruits, vegetables and low-fat and fat free dairy products, should continue to be encouraged.

Hypertension and kidney disease: a deadly connection

Kidney disease may be the cause or a consequence of hypertension. Hypertension affects 25% of the adult population in the United States. Similarly, chronic kidney disease (CKD) and end-stage renal disease (ESRD) have been steadily increasing in incidence because of the increasing age of the US population and rise in the incidence of risk factors, including hypertension. Substantial evidence supports the notion that elevated blood pressure is the most significant risk factor for developing CKD. Microalbuminuria has been shown to be the early marker of hypertensive renal disease. Furthermore, therapy to reduce microalbuminuria was associated with delayed progression of renal disease. Black Americans are at higher risk for developing hypertensive nephrosclerosis than whites. Hypertension is a major risk factor for cardiovascular events in patients with CKD and ESRD and those who have undergone renal transplantation. Studies have documented that elevated serum creatinine and CKD are risk factors for a cardiovascular event. Tight blood pressure control has been shown to reduce microalbuminuria and proteinuria and to delay progression of renal disease. Tailoring antihypertensive medication to the clinical setting to achieve a blood pressure goal is critical in reducing complications from this deadly connection.

Predictors of blood pressure response to angiotensin receptor blocker/diuretic combination therapy: a secondary analysis of the irbesartan/hydrochlorothiazide blood pressure reductions in diverse patient populations (INCLUSIVE) study

The secondary analysis of the Irbesartan/Hydrochlorothiazide Blood Pressure Reductions in Diverse Patient Populations (INCLUSIVE) clinical trial investigated whether baseline demographic and clinical variables are predictive of different degrees of blood pressure reduction following an angiotensin II receptor blocker/diuretic treatment regimen. Irbesartan/hydrochlorothiazide and other angiotensin receptor blocker combinations with a diuretic have been shown to be effective in reducing systolic blood pressure in a diverse patient population previously uncontrolled on monotherapy. Ordinary least squares regression analysis was performed on the intent-to-treat population of the INCLUSIVE study to identify variables predictive of variations in blood pressure changes in response to irbesartan/hydrochlorothiazide combination therapy. Higher baseline systolic blood pressure, female sex, type 2 diabetes, and statin therapy were found to be predictive of additional blood pressure lowering with this combination. The impact of higher baseline systolic blood pressure and diabetic state on changes in systolic blood pressure were diminished in female patients compared with male patients. In conclusion, a significant correlation may exist between certain clinical/demographic characteristics and the extent of the therapeutic response with irbesartan/hydrochlorothiazide treatment.

Initial combination therapy with irbesartan/hydrochlorothiazide for hypertension: an analysis of the relationship between baseline blood pressure and the need for combination therapy

Hypertension treatment guidelines recommend initiating 2-drug therapy whenever blood pressure (BP) is > or =20 mm Hg systolic or > or =10 mm Hg diastolic above goal. This post hoc pooled analysis of 2 multicenter, randomized, double-blind, active-controlled forced-titration studies in 1235 patients with moderate and severe hypertension examined how baseline BP levels relate to the need for combination therapy by comparing the antihypertensive efficacy and tolerability of once-daily fixed-dose irbesartan/hydrochlorothiazide (HCTZ) 300/25 mg compared with irbesartan 300-mg or HCTZ 25-mg monotherapies. In study 1, patients with severe hypertension (seated diastolic BP [SeDBP] > or =110 mm Hg) were treated for 7 weeks with irbesartan or irbesartan/HCTZ combination therapy, with forced-titration after week 1. In study 2, patients with moderate hypertension (seated systolic BP [SeSBP] 160-180 mm Hg or SeDBP 100-110 mm Hg) were treated for 12 weeks with irbesartan/HCTZ, irbesartan monotherapy, or HCTZ monotherapy, with forced-titration after week 2. The relationship between baseline BP and the likelihood of achieving BP goals (SeSBP <140 mm Hg or SeDBP <90 mm Hg; SeSBP <130 mm Hg or SeDBP <80 mm Hg) as well as the antihypertensive response was evaluated at week 7/8. The need for combination therapy increased with increasing baseline BP and lower BP goals across the range of BP levels studied, with a comparable adverse effect profile to monotherapy. These results suggest that the likelihood of achieving an early BP goal for a given BP severity should be considered when choosing initial combination therapy vs monotherapy.

Racial disparities in living kidney donation: is there a lack of willing donors or an excess of medically unsuitable candidates?

BACKGROUND

Live kidney donation is safe for healthy donors and an effective treatment for patients with end-stage renal disease. Many potential donors are referred for live kidney donation, but only a small percentage donate. This study aims to determine reasons for nondonation and establish if racial differences exist.

METHODS

A retrospective database and chart review of all patients that were referred for potential live kidney donation from January 1, 2000 to December 31, 2004 was conducted.

RESULTS

In all, 30.3% of referred potential live kidney donors were lost to follow-up. Primary reasons for nondonation (n=1,050) included unsuitable donor health (43.1%) and recipient-based causes (41.3%). Immunologic incompatibility accounted for 9.7% of all nondonations. Racial differences indicated more African Americans had incompatible blood types (P=0.01) or ineligible recipients (26.7% vs. 14.4%, P<0.01). More non-African Americans donated (13.2% vs. 4.6%, P<0.01) or were halted because the potential recipient received another organ (living/cadaveric) (20.0% versus 7.9%, P<0.01). Nondonation due to overall donor health (including diabetes and hypertension) did not differ between races, but subanalysis indicated more African American nondonation was due to high body mass index (P=0.01).

CONCLUSIONS

Determining the reason behind nondonation is a first step towards understanding low rates of live kidney donation. More African American donor referrals are lost to follow-up while rates of other reasons were similar among races. This may indicate that African Americans are not more frequently medically unsuitable, but that the divergence in rates of live kidney donation is caused by a disparity in willingness to donate among African Americans.

Hypertension and kidney disease: A deadly connection

Kidney disease may be the cause or a consequence of hypertension. Hypertension affects 25% of the adult population in the United States. Similarly, chronic kidney disease (CKD) and end-stage renal disease (ESRD) have been steadily increasing in incidence because of the increasing age of the US population and rise in the incidence of risk factors, including hypertension. Substantial evidence supports the notion that elevated blood pressure is the most significant risk factor for the development of CKD. Microalbuminuria has been shown to be the early marker of hypertensive renal disease. Furthermore, therapy to reduce microalbuminuria was associated with delay in the progression of renal disease. Black Americans are at higher risk for developing hypertensive nephrosclerosis than whites. Hypertension is a major risk factor for cardiovascular events in patients with CKD and ESRD and those who have undergone renal transplantation. Studies have documented that elevated serum creatinine and CKD are risk factors for a cardiovascular event. Tight blood pressure control has been shown to reduce microalbuminuria and proteinuria and to delay progression of renal disease. Tailoring the choice of antihypertensive medication to the clinical setting to achieve a blood pressure goal is critical in reducing complications from this deadly connection.

Are Racial Differences in Antihypertensive Responsiveness Reflected in Usage After Stroke?

OBJECTIVE

We sought to evaluate whether differential antihypertensive responsiveness in blacks is reflected in discharge antihypertensive prescription patterns among patients hospitalized with an ischemic cerebrovascular event.

METHODS

We analyzed use of discharge antihypertensive medications among patients hospitalized with an ischemic cerebrovascular event in the California Acute Stroke Prototype Registry, examining rates in black patients compared with all other races combined. Generalized estimating equations were used to identify factors independently associated with receipt of any antihypertensive medication overall and with use of specific types of antihypertensives.

RESULTS

Data were collected on 794 consecutive patients treated at 11 hospitals. No significant differences were observed between rates of antihypertensive use in black patients (74%) when compared with all others (69%), either for overall use or for any specific category of antihypertensive, although there was a trend toward more frequent use of diuretics in black patients (P = .12). Results were similar when analysis was limited to those with a history of hypertension.

CONCLUSIONS

In spite of a known differential response to antihypertensives in blacks, we found no differences in discharge antihypertensive prescription patterns in black patients hospitalized with transient ischemic attack and ischemic stroke compared with other races.

High performance liquid chromatographic analysis of MS23 piperidine analog MSP001 in rat plasma

MSP001 is a newly synthesized piperidine analog of the lead antihypertensive compound MS23 that dually targets cAMP-specific type 4 phosphodiesterase and L-type calcium channels. We validated an analytical protocol for MSP001 in rat plasma using high performance liquid chromatographic method. A C18 column and a phosphate/acetonitrile buffer were used to perform the chromatographic separation. UV detection was carried out at 307 nm, a wavelength at which an absorption peak was detected for this group of compounds. The calibration curve for MSP001 was linear in the range from 25 to 10,000 ng/ml. The limit of quantification (LOQ) was 25 ng/ml. The results demonstrate that this method has high linearity (R=0.99995), compound specificity, and acceptable precision/accuracy. The protocol is suitable for in vivo pharmacokinetic studies on the compound.