Abstract P321: Hypertension-related Cardiovascular Mortality In Asian American Subgroups

Introduction: Cardiovascular disease (CVD) mortality rates are heterogenous among Asian American subgroups. To inform more precise prevention strategies, we identified patterns of hypertension-related CVD mortality in Asian American subgroups.

Methods: Among deaths with CVD (ICD-10: I00-I99) as the underlying cause and hypertensive disease (ICD-10: I10-I15) as underlying or contributing cause in 2018-2021 mortality data from CDC WONDER with concurrent population estimates from the IPUMS Current Population Survey, we calculated age standardized mortality rates (ASMR) and proportional mortality for non-Hispanic Asian (Asian Indian, Chinese, Filipino, Japanese, Korean, Vietnamese) and Hispanic adults, with non-Hispanic White as the reference.

Results: There were 37,746, 95,404, and 867,599 deaths in non-Hispanic Asian, Hispanic and non-Hispanic White groups, respectively. Among non-Hispanic Asian females, ASMR ranged from 41.6 (95% CI 40.0-43.3) per 100,000 population in Japanese to 52.6 (51.0-54.2) per 100,000 in Filipina women. Among non-Hispanic Asian males, ASMR ranged from 45.8 (43.3-48.2) per 100,000 in Korean to 81.0 (78.5-83.5) in Filipino men (Table). Proportional mortality was higher for all Asian American subgroups vs. non-Hispanic White individuals. Proportional mortality ratios ranged from 1.11 (Korean males) to 1.38 (Filipino males; Chinese and Filipina females), vs. non-Hispanic White individuals.

Conclusions: There was substantial variation in hypertension-related cardiovascular mortality among Asian American subgroups. All Asian subgroups had higher proportional mortality compared with non-Hispanic White individuals.

Abstract P108: Side Effects Of Initial Combination Versus Monotherapy For Patients With Hypertension

Clinical guidelines recommend initiating combination antihypertensive therapy for many patients with hypertension. However, data on the risk of side effects are limited. We evaluated side effects associated with initiating combination therapy versus monotherapy among patients with hypertension from Kaiser Permanente Southern California between 2008-2014. Patient characteristics, antihypertensive medication use, and possible side effects were collected using electronic health records. We examined the association of initial combination therapy and incidence of side effects including acute kidney injury, hypotension, injurious fall, hyperkalemia, hypokalemia, hyponatremia, or hyperuricemia using multivariable Cox Proportional hazards models. Of 164,805 patients, 44% initiated combination therapy (34% angiotensin converting enzyme inhibitor (ACEI)-thiazide diuretics (TD); 10% other combinations) and 56% initiated monotherapy (22% ACEIs; 16% TD; 11% beta blockers (BB); 7% calcium channel blockers). Incidence rates of side effects were between 3.8 for hyperkalemia to 55.5 for hypokalemia per 1000 person-yrs during median follow-up of 0.27-0.45 yrs. Initiation of ACEI-TD combination therapy was associated with a lower risk of hyperkalemia than ACEI monotherapy and a lower risk of hypokalemia than TD monotherapy ( Table ). Initiation of ACEI-TD combination therapy was associated with a higher risk of hyponatremia, hyperuricemia, and hypotension, but not associated with injurious falls when compared with other monotherapy groups. Monitoring for side effects following initiation of antihypertensive medication with combination therapy may be useful.

Abstract 270: Temporal Trends in Heart Failure Mortality in an Integrated Healthcare Delivery System, California and the US, 2001-2017

Background: In recent years declines in the rate of mortality attributable to cardiovascular diseases have slowed and mortality attributable to heart failure (HF) has increased.

Objective: To examine secular trends in mortality with HF as the underlying cause in Kaiser Permanente Southern California (KPSC), California, and the US among adults 45 years of age and older from 2001 and 2017.

Methods: KPSC mortality rates with HF as an underlying cause from 2001 to 2017 were derived through linkage with California State death files and were compared with rates in California and the US. Rates were age-standardized to the 2000 US Census population. Trends were examined overall and among men and women, separately, using best-fit Joinpoint regression models. Average annual percent change (AAPC) and 95% confidence intervals (CI) were calculated for the overall study period, and within earlier (2001-2011) and later (2011-2017) time periods.

Results: Between 2001-2017, age-adjusted mortality rates with HF as the underlying cause were lower comparing KPSC to California and the US. In KPSC, rates increased from 23.9 to 44.7 per 100,000 person-years (PY) in KPSC, representing an AAPC of 1.3% (95% CI 0.0%, 2.6%). (Table) During the same time period, HF mortality rates in California also increased from 33.9 to 46.5 per 100,000 PY (AAPC 1.5%, 95% CI 0.3%, 2.7%), while remaining unchanged in the US at 57.9 per 100,000 PY in 2001 and 2017 (AAPC 0.0%, 95% CI -0.5%, 0.5%). AAPCs were not statistically different comparing KPSC to both California and the US (all p > 0.05). Between 2001-2011, rates of HF mortality increased in KPSC (AAPC 1.3%, 95% CI 0.0, 2.6), non-significantly increased in California (AAPC 0.2%, 95% CI -0.8%, 1.2%) and decreased in the US (AAPC -2.1%, 95% CI -2.7%, -1.5%). Between 2011-2017, rates of HF mortality increased in KPSC (AAPC 1.3%, 95% CI 0.0%, 2.6%), California (AAPC 3.7%, 95% CI 1.0%, 6.5%), and the US (AAPC 3.6%, 95% CI 2.4%, 4.8%) except among KPSC women (AAPC 0.3% [95% CI -1.6%, 2.2%]).

Conclusion: Despite increases in HF mortality after 2011, rates of HF mortality were lower among KPSC compared to California and the US. Given the mortality burden of HF at older age, there is a need to improve HF prevention, treatment and management efforts earlier in life.

P5322Oxidized phospholipids on apolipoprotein B-100 among black US adults with and without PCSK9 loss-of-function variants

Background

High oxidized phospholipid-apolipoprotein B-100 (OxPL-apoB) levels are associated with an increased risk for coronary heart disease (CHD). Genetic PCSK9 loss-of-function (LOF) variants result in life-long lower levels of LDL-C and lipoprotein(a) and reduced CHD risk, but the association with OxPL-apoB is unknown.

Purpose

To estimate the association between PCSK9 LOF variants and OxPL-apoB levels among black adults.

Methods

Genotyping for LOF variants (Y142X and C679X) was conducted for 10,196 black Reasons for Geographic And Racial Differences in Stroke study participants. OxPL-apoB was measured using antibody E06 for all participants with LOF variants (n=241) and randomly selected participants, matched at a 1:3 ratio, without LOF variants (n=723). Low OxPL-apoB was defined as the bottom quartile of the population distribution (<1.6 nM). Prevalence ratios (PR) and 95% confidence intervals (CI) were calculated for the association between PCSK9 LOF variants and low OxPL-apoB levels adjusting for age, sex, and estimated glomerular filtration rate.

Results

Adults with versus without PCSK9 LOF variants had lower LDL-C and lipoprotein(a) and were less likely to be taking a statin. (Table) A higher proportion of adults with versus without PCSK9 LOF variants had low OxPL-apoB levels (30.3 vs 23.4, p=0.03). After adjustment for covariates, the PR of low OxPL-apoB was increased for participants with compared to without LOF variants (PR 1.31, 95% CI 1.00, 1.72).

Characteristics of REGARDS participants PCSK9 loss-of-function variant p-value Yes (n=241) No (n=723) Age, years, mean (SD) 63.7 (9.2) 63.8 (8.6) 0.81 Female, % 61.4 60.6 0.82 Diabetes, % 34.4 27.4 0.04 LDL-C, mg/dL, mean (SD) 85 (32) 118 (37) <0.001 Lp(a), nmol/L, median (25th, 75th percentile) 63.2 (30.4, 119.6) 80.4 (39.7, 138.4) 0.02 Statin use, % 13.3 30.4 <0.001 OxPL-apoB <1.6 nM, % 30.3 23.4 0.03 Abbreviations: LDL-C, low-density lipoprotein cholesterol; Lp(a), lipoprotein(a); LOF, loss-of-function; nM, nanomolar; OxPL-apoB, oxidized phospholipids on apolipoprotein B-100; PCSK9, proprotein convertase subtilisin/kexin type-9; REGARDS, REasons for Geographic And Racial Differences in Stroke; SD, standard deviation.

Conclusion

Among black adults, PCSK9 LOF variants were associated with lower OxPL-apoB levels.

Acknowledgement/Funding

Industry/academic collaboration between Amgen Inc., University of Alabama at Birmingham and the Icahn School of Medicine at Mt. Sinai; and U01NS041588

Trends in Use of High-Intensity Statin Therapy After Myocardial Infarction, 2011 to 2014

BACKGROUND

Data prior to 2011 suggest that a low percentage of patients hospitalized for acute coronary syndromes filled high-intensity statin prescriptions upon discharge. Black-box warnings, generic availability of atorvastatin, and updated guidelines may have resulted in a change in high-intensity statin use.

OBJECTIVES

The aim of this study was to examine trends and predictors of high-intensity statin use following hospital discharge for myocardial infarction (MI) between 2011 and 2014.

METHODS

Secular trends in high-intensity statin use following hospital discharge for MI were analyzed among patients 19 to 64 years of age with commercial health insurance in the MarketScan database (n = 42,893) and 66 to 75 years of age with U.S. government health insurance through Medicare (n = 75,096). Patients filling statin prescriptions within 30 days of discharge were included. High-intensity statins included atorvastatin 40 or 80 mg and rosuvastatin 20 or 40 mg.

RESULTS

The percentage of beneficiaries whose first statin prescriptions filled following hospital discharge for MI were for high-intensity doses increased from 33.5% in January through March 2011 to 71.7% in October through November 2014 in MarketScan and from 24.8% to 57.5% in Medicare. Increases in high-intensity statin use following hospital discharge occurred over this period among patients initiating treatment (30.6% to 72.0% in MarketScan and 21.1% to 58.8% in Medicare) and those taking low- or moderate-intensity statins prior to hospitalization (from 27.8% to 62.3% in MarketScan and from 12.6% to 45.1% in Medicare). In 2014, factors associated with filling high-intensity statin prescriptions included male sex, filling beta-blocker and antiplatelet agent prescriptions, and attending cardiac rehabilitation within 30 days following discharge.

CONCLUSIONS

The use of high-intensity statins following hospitalization for MI increased progressively from 2011 through 2014.

Abstract 188: Hospital and Regional Variation in Use of High-intensity Statins Following Myocardial Infarction Among Medicare Beneficiaries

Background: American College of Cardiology/American Heart Association guidelines published in 2013 recommend high-intensity statins (atorvastatin 40 or 80 mg or rosuvastatin 20 or 40 mg) for most adults ≤75 years of age with atherosclerotic cardiovascular disease (ASCVD). For adults >75 years of age with ASCVD, the guidelines recommend continuation of tolerated statins or initiation of moderate intensity statins for most patients.

Objective: To examine whether guideline concordant use of high-intensity statins following myocardial infarction (MI) among Medicare beneficiaries differed by hospital size, medical school affiliation, and region of the US in 2014 (after publication of the guidelines).

Methods: We identified 28,086 Medicare beneficiaries with fee-for-service and pharmacy coverage who filled a statin within 30 days following hospital discharge for MI in 2014. The analyses were restricted to 731 hospitals with at least 20 beneficiaries discharged for MI in 2014. Hospital size and medical school affiliation were determined from the American Hospital Association survey. In subgroups ≤75 and >75 years of age, we calculated the proportion of beneficiaries whose first statin fill after MI was a high-intensity statin by hospital, hospital size, medical school affiliation, and region.

Results: Among statin users ≤75 years of age, 10,696 (55%) beneficiaries filled a prescription for a high-intensity statin following MI. The percentage filling high-intensity statins range from 0-100% (25 th percentile 39%, 75 th percentile 69%) across hospitals. High-intensity statin use was more common following hospitalization at larger hospitals, hospitals with medical school affiliations, and those in New England ( Figure ). A lower percentage of Medicare beneficiaries >75 years of age filled high-intensity statins (n = 8,441, 44%), but patterns were similar across hospital characteristics and region.

Conclusions: Similar patterns of high-intensity statin use were present among individuals ≤75 years of age, in whom high-intensity statin use is guideline concordant, and individuals >75 years of age, in whom high-intensity statin use is not necessarily guideline concordant, suggesting that variation in high-intensity statin prescriptions may not be directly related to close adherence to guidelines.

The role of T cell subsets and cytokines in the pathogenesis of Helicobacter pylori gastritis in mice

Gastritis due to Helicobacter pylori in mice and humans is considered a Th1-mediated disease, but the specific cell subsets and cytokines involved are still not well understood. The goal of this study was to investigate the immunopathogenesis of H. pylori-induced gastritis and delayed-type hypersensitivity (DTH) in mice. C57BL/6-Prkdc(scid) mice were infected with H. pylori and reconstituted with CD4+, CD4-depleted, CD4+CD45RB(high), or CD4+CD45RB(low) splenocytes from wild-type C57BL/6 mice or with splenocytes from C57BL/6(IFN-gamma-/-) or C57BL/6(IL-10-/-) mice. Four or eight weeks after transfer, DTH to H. pylori Ags was determined by footpad injection; gastritis and bacterial colonization were quantified; and IFN-gamma secretion by splenocytes in response to H. pylori Ag was determined. Gastritis and DTH were present in recipients of unfractionated splenocytes, CD4+ splenocytes, and CD4+CD45RB(high) splenocytes, but absent in the other groups. IFN-gamma secretion in response to H. pylori Ags was correlated with gastritis, although splenocytes from all groups of mice secreted some IFN-gamma. Gastritis was most severe in recipients of splenocytes from IL-10-deficient mice, and least severe in those given IFN-gamma-deficient splenocytes. Bacterial colonization in all groups was inversely correlated with gastritis. These data indicate that 1) CD4+ T cells are both necessary and sufficient for gastritis and DTH due to H. pylori in mice; 2) high expression of CD45RB is a marker for gastritis-inducing CD4+ cells; and 3) IFN-gamma contributes to gastritis and IL-10 suppresses it, but IFN-gamma secretion alone is not sufficient to induce gastritis. The results support the assertion that H. pylori is mediated by a Th1-biased cellular immune response.

Role of Helicobacter pylori cag region genes in colonization and gastritis in two animal models

The Helicobacter pylori chromosomal region known as the cytotoxin-gene associated pathogenicity island (cag PAI) is associated with severe disease and encodes proteins that are believed to induce interleukin (IL-8) secretion by cultured epithelial cells. The objective of this study was to evaluate the relationship between the cag PAI, induction of IL-8, and induction of neutrophilic gastric inflammation. Germ-free neonatal piglets and conventional C57BL/6 mice were given wild-type or cag deficient mutant derivatives of H. pylori strain 26695 or SS1. Bacterial colonization was determined by plate count, gastritis and neutrophilic inflammation were quantified, and IL-8 induction in AGS cells was determined by enzyme-linked immunosorbent assay. Deletion of the entire cag region or interruption of the virB10 or virB11 homolog had no effect on bacterial colonization, gastritis, or neutrophilic inflammation. In contrast, these mutations had variable effects on IL-8 induction, depending on the H. pylori strain. In the piglet-adapated strain 26695, which induced IL-8 secretion by AGS cells, deletion of the cag PAI decreased induction. In the mouse-adapted strain SS1, which did not induce IL-8 secretion, deletion of the cagII region or interruption of any of three cag region genes increased IL-8 induction. These results indicate that in mice and piglets (i) neither the cag PAI nor the ability to induce IL-8 in vitro is essential for colonization or neutrophilic inflammation and (ii) there is no direct relationship between the presence of the cag PAI, IL-8 induction, and neutrophilic gastritis.