Abstract P379: Groceries for Black Residents of Boston to Stop Hypertension (GoFresh): A Randomized Clinical Trial

Background: Diet is a major cause of disparities in hypertension among Black adults. While the Dietary Approaches to Stop Hypertension (DASH) Eating Plan is proven to lower blood pressure (BP), access to DASH-patterned groceries is a major barrier for residents of urban food deserts.

Objective: To test whether dietitian-assisted, home-delivered, DASH-patterned groceries lower BP among Black adults with elevated BP who reside in Boston area food deserts.

Methods: The Groceries for Black Residents of Boston to Stop Hypertension (GoFresh) study is one of five projects in the RESTORE Network, an AHA-funded initiative focused on hypertension prevention. This individual level, parallel-arm trial will enroll up to 176 Black adults with a systolic BP (SBP) between 120 and <150 mm Hg, who reside in communities identified by the MA Department of Health as urban food deserts. Following a 1:1 randomization scheme, half of participants will be assigned to weekly sessions with a dietitian, who will assist in ordering DASH-patterned groceries online for home delivery. The remaining participants will receive an unrestricted monthly stipend (referent). Both interventions will last 3 months followed by a 9-month maintenance phase. The trial is powered to detect a difference in SBP (primary) of -5.8 mm Hg measured after 3 months (DASH vs stipend). Secondary outcomes are 24-hour ambulatory BP, body mass index, 24-hour urine sodium and potassium, hemoglobin A1C, lipids, and intake of fruits, vegetables, and saturated fat. Qualitative interviews will be conducted with 45 participants after 6 months to determine barriers and facilitators of long-term intervention maintenance. The study will establish a biorepository of blood and urine. A Community Advisory Board collaborates with the study team on all aspects of the trial.

Discussion: Findings from this study will inform ongoing work on scalable interventions to prevent hypertension among Black adults with implications for public and healthcare-based food supplementation programs.

Abstract 038: The Association Of Supine Hypertension Versus Standing Hypotension With Adverse Cardiovascular Events Among Middle-aged Adults

Background: Clinical management of orthostatic hypotension (OH) prioritizes the prevention of standing hypotension (HYP), sometimes at the expense of supine hypertension (HTN). It is unclear whether supine HTN is associated with adverse outcomes relative to standing HYP.

Objectives: To compare supine HTN and standing HYP among middle-aged adults with and without OH.

Methods: The Atherosclerosis Risk in Communities Study measured supine and standing blood pressure (BP) in adults aged 45-64 between 1987-1989. We defined OH as a positional drop in systolic BP ≥20 mmHg or diastolic BP ≥10 mmHg, supine HTN as a BP≥140/≥90 mmHg, and standing HYP as a BP≤105/≤65 mmHg. ARIC participants were followed >30 years. Coronary heart disease (CHD) and mortality were adjudicated; falls and syncope were based on hospital claims. We used adjusted Cox models that included both supine HTN and standing HYP.

Results: Of 12,580 participants (55% female, 26% Black, mean age 54±6) 5% had OH. Among those without OH (N=11936), 19% had supine HTN and 21% had standing HYP, while among those with OH (N=644), 11% had supine HTN and 34% had standing HYP. Supine HTN was associated with CHD (HR 1.49; 1.36, 1.63), syncope (HR 1.26; 1.15, 1.39), and all-cause mortality (HR 1.47; 1.38, 1.57), while standing HYP was only associated with all-cause mortality (HR 1.08; 1.00, 1.16) and to a lesser extent than supine HTN (P comparing coefficients <0.001) (Table). Associations did not differ for those with OH (P-interactions>0.25).

Conclusion: Supine HTN was associated with more adverse events than standing HYP, regardless of OH status, questioning conventional practices of prioritizing standing HYP among adults with OH.

Abstract P019: Clinical Impact Of A 3 Versus 5-minute Delay On Automated Office Blood Pressure Measurement

Background: Recent studies suggest that a reduced delay during automated office blood pressure (AOBP) measurement may be as accurate as a 5-minute delay. The clinical impact of this change compared to gold-standard assessments (i.e. 24-hour ambulatory BP monitoring, ABPM) has not been reported.

Objective: To compare the impact of a 3- vs 5-minute delay on AOBP and its relation with average awake-time ABPM.

Methods: Patients referred to a single hypertension (HTN) center had BP measurements with ABPM and one of two non-randomized, unattended AOBP protocols. Half of patients underwent AOBP with a 5-minute delay; the other half underwent AOBP with a 3-minute delay. All measurements were compared to the average awake-time ABPM. HTN was defined as SBP≥140 or DBP≥90 mmHg. We used linear regression adjusted for age, sex, and race to assess whether the 3-minute protocol was associated with a difference between mean AOBP and average awake-time ABPM.

Results: Among 100 participants (mean age 59.7±15.5 years, 58% women, 26% Black), the average awake-time BP was 132.6±14.8/77.4±11 for the 5-minute protocol and 134.4±17/78.2±11 for the 3-minute protocol. HTN misclassification between groups based on awake-ABPM was similar (14% for 5- versus 12% for 3-minute delay, p=0.51). Compared to 5-minute delay, 3-minute delay was not associated with a significant difference between mean AOBP and mean awake-time ABPM for SBP (2.3 mm Hg; 95% CI: -3.7, 8.2) or DBP (1.2 mm Hg; 95% CI: -2.5, 4.8).

Conclusion: Measuring AOBP with a 3-minute delay did not result in statistically different accuracy compared with average awake-time ABPM. However, this finding should be confirmed in a larger, clinic-based sample.

Abstract P207: The Feasibility Of A 6-week, Pharmacist-Led, Self-Monitored Blood Pressure Treatment Program

Background: Guidelines recommend concomitant out-of-office blood pressure (BP) measurements with telehealth counseling for titration. While high quality home BP measurement coupled with pharmacist care reduces the time needed to achieve BP goal, it remains unclear how rapidly BP titrations can be applied in clinical practice.

Objective: To examine the impact of home BP monitoring coupled with a rapid, biweekly, pharmacist-led BP medication titration program on BP control and patient safety.

Methods: Forty patients were referred if BP ≥140/90, using ≤2 anti-hypertensive medications, and failed a trial of lifestyle modification. The initial visit with the pharmacist included validation of home BP monitor compared with an Omron HEM-907XL. Patients monitored BP twice daily in the morning and evening for a week then had their medication regimen adjusted every 2 weeks until reaching their goal or completing a 6-week follow-up period.

Results: Of the 29 patients completing the program, mean enrollment SBP/DBP was 155.2 (SD, 15.8)/89.7 (SD, 11.5) mm Hg. The completion SBP/DBP was 132.1 (SD, 10.9)/ 77.6 (SD, 10). The number of HTN medications prescribed increased by an average of 0.3 (from 1.3 to 1.6) over the follow-up period. There were no incidences of falls or hypotension. One patient had a clinically significant electrolyte change requiring medication adjustment. Two patients had a clinically significant change in serum creatinine, but both stabilized after altering their hypertension medication regimen.

Conclusion: A 6-week, pharmacist-led, home BP monitoring program with rapid titration had high retention and increased the percentage of patients achieving BP goals without safety concerns.

Abstract P010: Performance Of Home Blood Pressure Monitors In The Clinical Setting

Background: Self-measured blood pressure (SMBP) monitoring is increasingly used for remote management of hypertension, but the real-world performance of home BP devices remains unsettled.

Objectives: To determine the performance of home BP devices among patients with hypertension using the American Medical Association’s (AMA) Self-Measured Blood Pressure Device Accuracy Test protocol.

Methods: Patients at a single hypertension clinic underwent up to five seated, same-arm BP readings using home monitors and an automated BP machine (Omron HEM-907XL). Following the AMA’s 3-step protocol, we used the home device for the first, second, and fourth measures and the office device for the third and fifth (if needed) measures. Device failure was defined as an absolute difference in systolic BP >10 mm Hg between the home and office monitors in either Step 2 or Step 3. Patient factors associated with failure were examined via logistic regression models adjusted for age, sex, and race.

Results: We evaluated 152 patients (mean age 60 ± 15 years, 58% women, 31% Black) seen between October 2020 and November 2021. Device failure occurred in 21.7% (95% CI: 15.8, 29.0) of devices tested, including 18.1% among Omron devices and 27.6% among non-Omron devices ( P = 0.08) ( Table ). Higher BMI was associated with higher odds of device failure (OR: 1.09; 95% CI: 1.01, 1.17) though age, sex, and race were not associated with device failure.

Conclusions: Over one-fifth of home devices failed accuracy testing using the AMA SMBP protocol. Higher BMI was associated with device failure. These findings confirm the importance of office-based monitor verification to ensure the accuracy of home BP monitoring.

Abstract MP59: Effects Of Sodium Reduction And Weight Loss On Lightheadedness And Falls In Older Adults: Results From TONE

Background: The Trial of Nonpharmacologic Interventions in the Elderly (TONE) demonstrated the efficacy of sodium reduction and weight loss to reduce hypertension medication use in older adults. However, adverse events related to lightheadedness and falls have not been reported.

Objective: To determine whether sodium reduction and weight loss are associated with greater risk of lightheadedness and falls among older adults.

Methods: TONE was a randomized trial of 60-80 year-old adults with systolic BP (SBP) and diastolic BP (DBP) below 145 and 85 mm Hg, respectively, while receiving treatment with a single antihypertensive medication. Participants were randomized to behavioral interventions focused on sodium reduction, weight loss, both, or neither (usual care); 3 months after randomization, the antihypertensive medication was withdrawn and only restored later during the study if needed for uncontrolled hypertension. Total follow-up was 36 months post-randomization. Two physicians independently adjudicated adverse event logs, masked to intervention assignment. The primary outcome was a composite of the first occurrence of adverse event related to falls (total N=95): 72 involved orthostatic symptoms (lightheadedness, dizziness, vertigo), while 23 involved hard events (fall or syncope). Hazard ratios were determined via Cox proportional hazards models.

Results: Among the 975 participants (mean age 66 yrs, 48% women, 24% black), mean SBP and DBP were 128 and 71 mm Hg. The cumulative incidence of adverse events at 30 months was 0.08, 0.13, 0.11, and 0.14 for usual care, reduced sodium, weight loss, or both, respectively ( Figure ). In adjusted multi-variable analyses, sodium reduction was associated with higher risk of an adverse event (HR 1.52; 95% CI: 1.02, 2.27), while weight loss was not associated with adverse events (HR 1.18; 0.77, 1.79).

Conclusions: In the context of antihypertensive medication withdrawal, sodium reduction was associated with a higher risk of fall-related adverse events, predominantly symptoms.

Abstract MP36: Effects Of Intensive Blood Pressure Treatment On Orthostatic Hypotension: An Individual-level Meta-analysis

Background: Intensive blood pressure (BP) treatment reduces the risk of cardiovascular disease, but there are ongoing concerns that it also might be harmful by increasing the risk of orthostatic hypotension (OH). However, individual trials have been inconclusive.

Methods: In this individual participant data meta-analysis, we systematically reviewed MEDLINE, EMBASE, and CENTRAL databases through October 7, 2019 for randomized trials of BP pharmacologic treatment (more intensive BP goal or active agent) on measured OH. OH was defined as a drop in SBP ≥20 mmHg or DBP ≥10 mmHg after changing positions from seated to standing. Ultimately, five trials of BP treatment goal were identified. Effects were examined overall and in subgroups of baseline characteristics, including diabetes, standing BP pre-randomization (<110 vs ≥110 mm Hg), and pre-randomization OH.

Results: There were 18,466 participants with 127,998 follow-up visits. Most trials demonstrated low risk of bias with minimal heterogeneity of effects across trials ( I 2 = 0.0%). Intensive BP treatment significantly lowered risk of OH (OR 0.93; 95% CI: 0.86, 0.99). Effects were strongest among adults without diabetes (OR 0.90 vs 1.10; P -interaction = 0.015) and adults with lower standing SBP (OR 0.66 for <110 mmHg vs 0.96 for ≥110 mmHg; P -interaction = 0.02). Effects did not differ by pre-randomization OH ( P -interaction = 0.80). In sensitivity analyses that included 4 additional placebo-controlled trials, overall and subgroup findings were unchanged ( Figure ).

Conclusion: OH prior to or in the setting of more intensive BP treatment should not be viewed as a reason to avoid or to de-escalate treatment for hypertension.

Repair of central slip avulsions using Mitek Micro Arc bone anchors. An in vitro biomechanical assessment

In this study we evaluated the pullout strength of the Mitek Micro Arc anchor for the reconstruction of central slip avulsions at the proximal interphalangeal joint of the finger. Forty paired fresh frozen cadaver fingers were randomized into treatment (anchor) and control groups (horizontal mattress repair) and subjected to tensile loading to failure. The mean (SD) failure loads of the repairs were: Mitek repair group 22.3 (4.7) N, and control group 24.7 (5.5) N. There were no statistically significant differences between the failure loads or the failure mechanisms of the two repairs. The pullout strength of the isolated anchor-bone complex was evaluated by refitting five anchors with stainless steel wire. The mean failure load of the isolated anchor was 400% higher than the tendon-suture-anchor complex, indicating that the weakest link of the system is not the bone-anchor interface.

Transferrin receptors in the human gastrointestinal tract. Relationship to body iron stores

Fluorescently labeled antibodies were used to identify transferrin receptors and mucosal transferrin in human gastrointestinal biopsy sections. Transferrin receptors were evident in the villous epithelium and the crypt areas of duodenum, ileum, and colon, predominantly in the basal-lateral area. In 7 subjects with low iron stores, the intensity of duodenal villous staining for receptor, on a scale of 0-4, was 2.1 +/- 0.3 (mean +/- SD). This value was significantly higher than the value in 13 subjects with normal iron stores (1.1 +/- 0.4). In 5 patients with hereditary hemochromatosis, duodenal transferrin receptor staining was not significantly different from that in the subjects with normal iron stores. Transferrin staining was found in the apical cytoplasm of epithelial cells in the duodenum, ileum, and colon, but observer assessment was not sufficiently reproducible to make a quantitative analysis. Our results suggest that iron deficiency is accompanied by an increase in transferrin receptors in duodenal absorptive cells, and the genetic lesion in hemochromatosis does not involve an increase in transferrin receptors in the intestinal mucosa compared with subjects with normal iron stores.

Dual-isotope method for determination of human zinc absorption: the use of a test meal of turkey meat

The percentage of 65Zn taken up (absorbed) from extrinsically labeled turkey meat was calculated from the amounts of 65Zn and a nonabsorbed 51Cr marker present in the body or in a single stool specimen after 1-2 d. 51CrCl3 proved to be a suitable marker for unabsorbed 65Zn and so the early determination of 65Zn absorption was possible. With stool counting, 65Zn absorption data from first stool samples after 1-2 d were accurate as judged by correlation with the amount of 65Zn in the body 7-10 d later (retention); results from subsequent stools gave lower absorption values due to the early excretion of some absorbed 65Zn. The dual-isotope method gave reproducible results when four successive tests of zinc absorption were carried out in a group of six subjects. The average (mean +/- SD) 65Zn absorption from turkey meals containing 31 mumol (2 mg) and 46 mumol (3 mg) of zinc was 39 +/- 8% and 29 +/- 6%, respectively, measured by stool counting; 65Zn absorption and retention correlated well in both studies. A series of different beverages was given in place of water with the turkey meal. Orange juice significantly reduced 65Zn absorption and milk also showed this tendency, but tea, whiskey, wine or beer had no significant effect on the absorption of 65Zn from the turkey meal. In groups of subjects the mean ratio of 65Zn absorption from extrinsically labeled turkey meat on two occasions (1.06) was not significantly different from that of the absorption of extrinsic to intrinsic 65Zn labels (1.16). The dual-isotope technique with either stool or body counting is suitable for the rapid determination of 65Zn absorption from extrinsically labeled turkey within 2 d.