Identifying Patients for Intensive Blood Pressure Treatment Based on Cognitive Benefit: A Secondary Analysis of the SPRINT Randomized Clinical Trial

Importance

Intensive vs standard treatment to lower systolic blood pressure (SBP) reduces risk of mild cognitive impairment (MCI) or dementia; however, the magnitude of cognitive benefit likely varies among patients.

Objective

To estimate the magnitude of cognitive benefit of intensive vs standard systolic BP (SBP) treatment.

Design, Setting, and Participants

In this ad hoc secondary analysis of the Systolic Blood Pressure Intervention Trial (SPRINT), 9361 randomized clinical trial participants 50 years or older with high cardiovascular risk but without a history of diabetes, stroke, or dementia were followed up. The SPRINT trial was conducted between November 1, 2010, and August 31, 2016, and the present analysis was completed on October 31, 2022.

Intervention

Systolic blood pressure treatment to an intensive (<120 mm Hg) vs standard (<140 mm Hg) target.

Main Outcomes and Measures

The primary outcome was a composite of adjudicated probable dementia or amnestic MCI.

Results

A total of 7918 SPRINT participants were included in the analysis; 3989 were in the intensive treatment group (mean [SD] age, 67.9 [9.2] years; 2570 [64.4%] men; 1212 [30.4%] non-Hispanic Black) and 3929 were in the standard treatment group (mean [SD] age, 67.9 [9.4] years; 2570 [65.4%] men; 1249 [31.8%] non-Hispanic Black). Over a median follow-up of 4.13 (IQR, 3.50-5.88) years, there were 765 and 828 primary outcome events in the intensive treatment group and standard treatment group, respectively. Older age (hazard ratio [HR] per 1 SD, 1.87 [95% CI, 1.78-1.96]), Medicare enrollment (HR per 1 SD, 1.42 [95% CI, 1.35-1.49]), and higher baseline serum creatinine level (HR per 1 SD, 1.24 [95% CI, 1.19-1.29]) were associated with higher risk of the primary outcome, while better baseline cognitive functioning (HR per 1 SD, 0.43 [95% CI, 0.41-0.44]) and active employment status (HR per 1 SD, 0.44 [95% CI, 0.42-0.46]) were associated with lower risk of the primary outcome. Risk of the primary outcome by treatment goal was estimated accurately based on similar projected and observed absolute risk differences (C statistic = 0.79). Higher baseline risk for the primary outcome was associated with greater benefit (ie, larger absolute reduction of probable dementia or amnestic MCI) of intensive vs standard treatment across the full range of estimated baseline risk.

Conclusions and Relevance

In this secondary analysis of the SPRINT trial, participants with higher baseline projected risk of probable dementia or amnestic MCI gained greater absolute cognitive benefit from intensive vs standard SBP treatment in a monotonic fashion.

Trial Registration

ClinicalTrials.gov Identifier: NCT01206062.

Kidney Disease, Intensive Hypertension Treatment, and Risk for Dementia and Mild Cognitive Impairment: The Systolic Blood Pressure Intervention Trial

BACKGROUND

Intensively treating hypertension may benefit cardiovascular disease and cognitive function, but at the short-term expense of reduced kidney function.

METHODS

We investigated markers of kidney function and the effect of intensive hypertension treatment on incidence of dementia and mild cognitive impairment (MCI) in 9361 participants in the randomized Systolic Blood Pressure Intervention Trial, which compared intensive versus standard systolic BP lowering (targeting <120 mm Hg versus <140 mm Hg, respectively). We categorized participants according to baseline and longitudinal changes in eGFR and urinary albumin-to-creatinine ratio. Primary outcomes were occurrence of adjudicated probable dementia and MCI.

RESULTS

Among 8563 participants who completed at least one cognitive assessment during follow-up (median 5.1 years), probable dementia occurred in 325 (3.8%) and MCI in 640 (7.6%) participants. In multivariable adjusted analyses, there was no significant association between baseline eGFR <60 ml/min per 1.73 m² and risk for dementia or MCI. In time-varying analyses, eGFR decline ≥30% was associated with a higher risk for probable dementia. Incident eGFR <60 ml/min per 1.73 m² was associated with a higher risk for MCI and a composite of dementia or MCI. Although these kidney events occurred more frequently in the intensive treatment group, there was no evidence that they modified or attenuated the effect of intensive treatment on dementia and MCI incidence. Baseline and incident urinary ACR ≥30 mg/g were not associated with probable dementia or MCI, nor did the urinary ACR modify the effect of intensive treatment on cognitive outcomes.

CONCLUSIONS

Among hypertensive adults, declining kidney function measured by eGFR is associated with increased risk for probable dementia and MCI, independent of the intensity of hypertension treatment.

FRAILTY STATUS, COGNITIVE IMPAIRMENT, AND THE EFFECTS OF INTENSIVE BLOOD PRESSURE CONTROL

Background: Frailty associates with cognitive decline and incident dementia in older adults. The Systolic Blood Pressure Intervention Trial (SPRINT) has highlighted blood pressure (BP) control as a potentially modifiable risk factor for cognitive impairment. Using data from SPRINT, we explore whether frailty status, based on a frailty index (FI), prospectively associates with mild cognitive impairment (MCI) and dementia, and whether the effect of intensive BP control on these outcomes varies by frailty status. Methods: SPRINT randomized participants to either to an systolic BP goal of &lt;120 mmHg (intensive treatment) or a goal of &lt;140 mmHg (standard treatment). We used Cox regression to model the association of the FI with MCI and dementia, and to conduct subgroup analyses by frailty status for the effect of intensive treatment. Results: We include 9307 participants, with the majority categorized as pre-frail (0.100.21, 38.0%). Adjusting for age, sex, race/ethnicity, education, and treatment group, a 0.1 increase in the FI was associated with increased risk for MCI (Hazard Ratio (HR) = 1.42, 95% CI: 1.29, 1.58) and dementia (HR = 1.80, 95% CI: 1.56, 2.08). There was weak evidence of an interaction between frailty status and intensive treatment for the composite outcome of MCI and dementia (p=0.03), with a beneficial effect of intensive treatment in pre-frail participants (HR=0.71 95% CI: 0.58, 0.89), and a largely null effect in frail participants (HR=0.98, 95% CI: 0.82, 1.18). Conclusions: Frailty status may modify the effect of intensive BP control on MCI and dementia.

Neuromuscular Electrical Stimulation Combined with Protein Ingestion Preserves Thigh Muscle Mass But Not Muscle Function in Healthy Older Adults During 5 Days of Bed Rest

Short-term bed rest in older adults is characterized by significant loss in leg lean mass and strength posing significant health consequences. The purpose of this study was to determine in healthy older adults if the daily combination of neuromuscular electrical stimulation and protein supplementation (NMES+PRO) would protect muscle mass and function after 5 days of bed rest. Twenty healthy older adults (∼70 years) were subjected to 5 days of continuous bed rest and were randomized into one of two groups: NMES+PRO (n = 10) or control (CON) (n = 10). The NMES+PRO group received bilateral NMES to quadriceps (40 minutes/session, 3 × /day; morning, afternoon, and evening) followed by an interventional protein supplement (17 g). The CON group received an isocaloric equivalent beverage. Before and after bed rest, vastus lateralis biopsies occurred before and after acute essential amino acid (EAA) ingestion for purposes of acutely stimulating mechanistic target of rapamycin (mTORC1) signaling, a major regulator of muscle protein synthesis, in response to bed rest and NMES+PRO. Baseline (pre and post bed rest) muscle samples were also used to assess myofiber characteristics and gene expression of muscle atrophy markers. Thigh lean mass and muscle function were measured before and after bed rest. Five days of bed rest reduced thigh lean mass, muscle function, myofiber cross-sectional area, satellite cell content, blunted EAA-induced mTORC1 signaling, and increased myostatin and MAFbx mRNA expression. Interestingly, NMES+PRO during bed rest maintained thigh lean mass, but not muscle function. Thigh muscle preservation during bed rest with NMES+PRO may partly be explained by attenuation of myostatin and MAFbx mRNA expression rather than restoration of nutrient-induced mTORC1 signaling. We conclude that the combination of NMES and protein supplementation thrice a day may be an effective therapeutic tool to use to preserve thigh muscle mass during periods of short-term hospitalization in older adults. However this combined intervention was not effective to prevent the loss in muscle function.

Identifying failure to thrive in the long term care setting

INTRODUCTION AND RATIONALE

Geriatric failure to thrive (GFTT) is commonly encountered in the long term care (LTC) setting. This syndrome of unexplained functional decline can be approached in a methodical manner. The updated Minimum Data Set (MDS) 3.0, now implemented in almost all skilled nursing facilities, includes pertinent clinical information that could be used to identify residents who manifest GFTT. A screening tool using data from the MDS 3.0 could be used by LTC providers to evaluate LTC residents.

METHODS

A literature review was completed to identify articles focused on (1) GFTT in the LTC setting and (2) tools to identify GFTT. Common components of GFTT were matched with items collected as part of the MDS 3.0 with a goal to determine its utility as a screening tool to identify GFTT in the LTC setting.

OUTCOMES AND DISCUSSION

The MDS 3.0 includes assessment of numerous components commonly observed in patients with GFTT. By using clinically validated tools, the MDS 3.0 may assist in the recognition of LTC residents with or at risk for GFTT. Once GFTT is recognized, the LTC interdisciplinary team can then identify potentially reversible causes, set goals of care, and develop a comprehensive care plan that may include diagnostic measures, curative interventions, and/or palliative measures individualized to the resident.

Effect of losartan in aging-related endothelial impairment

Aging is associated with progressive deterioration in endothelial function. We hypothesized that losartan may represent a useful therapeutic strategy to ameliorate endothelial function in aged subjects. Eighteen healthy older subjects (mean age 75 +/- 3 years) were prospectively randomized in a double-blind, crossover fashion to receive either losartan 50 mg/day or placebo for 6 weeks. Subjects were switched to the opposite arm after a 2- week washout period. Flow-mediated dilation (FMD) in the brachial artery and plasma levels of vascular cell adhesion molecule-1, intercellular adhesion molecule (ICAM), moncocyte chemoattractant 1 protein, and E-selectin were measured in both arms at the beginning and end of the 6-week period. Losartan resulted in a 6-mm Hg decrease in systolic blood pressure (from 130 +/- 12 to 124 +/- 13 mm Hg), which was no different from placebo (132 +/- 12 to 127 +/- 13 mm Hg). FMD increased from 3.1 +/- 0.6% to 3.9 +/- 0.6% after losartan, and decreased from 3.3 +/- 0.3% to 2.4 +/- 0.6% after placebo (p = NS for both). In contrast, losartan reduced circulating concentrations of vascular cell adhesion molecule 1 (750 +/- 73 to 572 +/- 39), ICAM (405 +/- 26 to 196 +/- 10), and moncocyte chemoattractant 1 protein (560 +/- 56 to 423 +/- 35) (p <0.01 for all by analysis of variance), but not E-selectin. On univariate analyses, the strongest predictor of baseline endothelial function and change in FMD with losartan was low-density lipoprotein. There was a negative correlation between baseline endothelial function and change in FMD in response to losartan (r(2) = -0.75, p = 0.0003). Baseline ICAM levels alone significantly correlated with low-density lipoprotein cholesterol (r(2) = 0.54, p = 0.02) and weakly correlated with total cholesterol (r(2) = 0.47, p = 0.05). Thus, administration of losartan for a duration of 6 weeks has favorable effects on inflammatory markers in healthy older subjects, but does not alter peripheral conduit endothelial function.

Glucose transporter content and enzymes of metabolism in nerve-repair grafted muscle of aging Fischer 344 rats

Aging and grafting are associated with decreased ability of muscle to sustain power, likely reflecting diminished fuel availability. To assess mechanisms that may contribute to availability of glucose, we studied GLUT-1 and GLUT-4 protein as well as mRNA contents and enzymes of glucose metabolism in grafted and control medial gastrocnemius (MG) muscles of 6-, 12-, and 24-mo-old male Fischer 344 rats. There was no effect of age or grafting on MG GLUT-4 content. There was both an age- and graft-associated increase in GLUT-1 content (P = 0.0044 and 0.0063, respectively). There was no effect of aging or grafting on hexokinase and phosphofructokinase activity or on protein and glycogen content. Muscle mass and citrate synthase activity were significantly diminished with grafting. Citrate synthase activity was significantly greater in the 12-mo-old compared with the 6- and 24-mo-old animals. Grafting in combination with aging had no impact on any of the parameters measured. We conclude that diminished glucose transporter expression cannot explain the decreased ability of aged muscle to sustain power. In addition, we conclude that the diminished ability of the grafted MG muscle to sustain power may be explained, in part, by a decrease in energy available from oxidative metabolism.