Clinical Research Directory

Wild Blueberries for Gut, Brain, and Heart Health in Adults With High Blood Pressure

The purpose of the study is to determine the effectiveness of wild blueberries on cardiovascular health, cognitive function, and gut microbiota composition in non-Hispanic Black and White adults with elevated blood pressure.

Wild Blueberries for Gut, Brain, and Cardiometabolic Health in Prediabetes

The goal of this clinical trial is to determine the effectiveness of using a freeze-dried wild blueberry powder on cardiometabolic health, cognitive function, and gut microbiota composition in adult women with prediabetes.

The Stroke Aetiology and VascuLar Disease in Stroke and TIA Study - A Clinical Study Analysing the Effects on Cardiovascular Health and Disease With an Extended Investigation Into Conditions Causative of Stroke and Concomitant Cardiovascular Disease in Patients Admitted for Acute Stroke or TIA

Annually, about 4000 Swedes suffer a recurrent stroke, and for many, their lives change dramatically. To prevent recurring strokes, knowledge about the individual's risk of recurrence is needed to tailor an effective preventive medical treatment. The purpose of the SALSA study is to investigate whether an expanded risk assessment and subsequent treatment can reduce the recurrence of stroke in study patients. Stroke, i.e., infarction/bleeding in the brain, has several different causes that individually or together constitute the risk of recurrence. Furthermore, stroke patients often have concomitant vascular diseases in other vascular beds, which further increases the risk. Every fourth patient with acute stroke or transient ischemic attack (TIA) admitted to any of the stroke wards at Danderyd Hospital, Stockholm, Sweden, is consecutively invited to participate in the SALSA study. Those who accept the study invitation, receive an expanded investigation of the most common causes of cerebral infarction (atherosclerosis, atrial fibrillation, narrowing of the brain\'s small vessels) or brain haemorrhage (presence of the protein amyloid in the vessels, high blood pressure). Due to the high risk of stroke patients having a vascular disease, such as atherosclerosis, the presence of arterial stiffness in the aorta, 24-hour blood pressure, and blood circulation in the legs are examined at the follow-up visit. If vascular disease is detected, expanded preventive treatment is provided. Neither a general investigation of the most common stroke aetiologies in addition to the one assessed to have caused the current stroke nor examinations of other vascular beds are recommended in national stroke guidelines. In addition to the extended risk assessment, the patient will get a written treatment program tailored after the individual patient's risk profile. The compliance to this treatment program will be assessed during a return visit one year after the hospital stay. After this visit, the active participation in the study is completed for the study participant. During the remainder of the follow-up, the study participant will be followed in national medical registers. The remaining 3/4 of patients at Danderyd Hospital constitute the comparison group, who are investigated and treated according to routine and hence do not undergo the additional vascular examinations. Stroke recurrence and other cardiovascular events occurring within the next 5-10 years will be compared between study patients and the comparison group via the national stroke registry containing all stroke and TIA patients at Danderyd Hospital.

The Effect of Lipoprotein (a) on Arterial Stiffness, Endothelial Function and Myocardial Deformation

1. Introduction Lipoprotein(a), or Lp(a), is a type of lipoprotein that is structurally similar to LDL (low-density lipoprotein) but carries an additional protein called apolipoprotein (a). 2. Purpose of the Study The primary purpose of this study is to investigate the effect of Lp(a) levels on arterial stiffness, endothelial function, and left atrial (LA) and left ventricular (LV) deformation over a 12-month follow-up period. Secondarily, the study will investigate: * a) The incidence of major adverse cardiovascular events (MACE), including cardiovascular death, acute myocardial infarction, and acute stroke. * b) The correlation between MACE incidence and parameters of arterial stiffness, endothelial function, and LA/LV deformation. * c) The levels of oxidative load markers. 3. Materials and Methods This observational study will include adults aged 18-75 years (regardless of gender) who visit the outpatient clinics of the 2nd University Cardiology Clinic at "Attikon" General Hospital. All participants will sign a consent form. A full medical history, clinical examination, and blood collection will be performed to determine levels of Total Cholesterol, LDL-C, HDL-C, triglycerides, and Lp(a) at each visit.. Participants will be divided into three groups: * Group A: Lp(a) ≥50 mg/dL with Total Cholesterol\<200 mg/dl * Group B : Lp(a) \<50 mg/dL. with Total Cholesterol\>200 mg/dl * Group C (Control): Lp(a) \<50 mg/dL. with Total Cholesterol\<200 mg/dl At each group n ≥ 100 participants are anticipated. Measurements at baseline, at 6 and at 12 months: * Arterial Stiffness: Determination of carotid-femoral pulse wave velocity (cf-PWV) using the Complior SP device and 24-hour pulse wave analysis with the Mobil-O-Graph device. * Endothelial Function: Measurement of the endothelial glycocalyx thickness of sublingual capillaries using a Sidestream Dark Field (SDF) camera (GlycoCheck). This is expressed through the perfused boundary region (PBR) index. * Cardiac Deformation: Use of two-dimensional strain (speckle tracking) to calculate the Global Longitudinal Strain (GLS) of the LV and LA strain. * Oxidative Load: Determination of malondialdehyde (MDA) and protein carbonyls (PCs) levels as markers of oxidative stress using spectrophotometric kits. Statistical Analysis: Comparisons regarding the changes in these markers over 6 and 12 months will be conducted between the three groups.

Natural History Study of CADASIL

Background: CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarct and leukoencephalopathy) is a genetic disorder. It causes narrowing of the small blood vessels and can lead to strokes and dementia. Researchers want to monitor people with CADASIL over time. Objective: To learn more about how CADASIL affects a person s blood vessels over time. Eligibility: Adults ages 18 and older who have CADASIL, and healthy volunteers. Design: Participants will be screened with a medical record review. Participants will have 4 study visits over 9 years. Visits will last 6 8 hours per day, for 2 4 days. Participants will give blood and urine samples. They will have an electrocardiogram to record their heart s electrical activity. They will fill out a family tree. They will have tests that measure mental abilities like memory and attention. They may have a skin biopsy. They may have a lumbar puncture. Participants will have an eye exam. Their pupils will be dilated. They will receive a dye via intravenous (IV) line. Pictures will be taken of their eyes. Participants will have an imaging scan of their brain. They may receive a contrast agent via IV. Participants blood flow and blood vessel flexibility will be measured. In one test, a probe will be pressed against the skin of the their wrist, neck, and groin. In another test, they will hold one arm still while a microscope makes videos of the blood flow through a fingernail. In another test, they will perform light exercise or other activities while wearing an elastic band around their head or probes placed on their arm or leg. Healthy volunteers will complete some of the above tests.

The InterVitaminK Trial - Effects of Vitamin K Supplementation on Cardiovascular, Metabolic, and Bone Health

The purpose of this study is to examine the effect of menaquinone-7 (MK-7) supplementation on cardiovascular, metabolic, and bone health.

Empagliflozin Reversal of Arterial StiffnEss in Aging

Randomized placebo-controlled clinical trial in a cohort of males (n=40) and females (n=40), 60-80 years of age, with the hypothesis that SGLT2 inhibition with empagliflozin (10mg/day for 12 weeks) reduces aging-related arterial stiffening.

Arterial Stiffness in Individuals With Breast Cancer

The aim of this study was to evaluate vascular toxicity induced by anthracyclines and other anticancer drugs and to measure arterial stiffness in women with breast cancer and, in addition, to evaluate the acute and chronic arterial stiffness responses of upper extremity aerobic exercise training.

Effects of Cross-sex Hormone Therapy on Eating Behavior, Metabolism, Energy Balance and Cardiovascular System

Current study aims to characterize five highly interconnected physiological systems in patients undergoing cross-sex hormone therapy - namely glucose and lipid metabolism, energy balance, eating behavior, functional brain networks involved in the regulation of eating behavior and the cardiovascular system - to gain novel insights into the effects of sex hormones on the human body. Gathered information will help to identify pathophysiological mechanisms for the development of overeating/obesity, insulin resistance, and cardiovascular disease. Secondarily, the relationships between the gut and oral microbiomes and metabolomes and circulating bacterial signatures will be investigated in relation to the other pervasive physiological systems. Current study is an observational study. The decision if the patient's request for cross-sex hormone therapy can complied with (i.e., if cross-sex hormone therapy is medically indicated) is made prior to the first contact with the study center and with the outpatients clinic for Endocrinology at the University Hospital in Leipzig. Decision ifor treatment is made according to national and international guidelines. Treatment of study participants with testosterone and estradiol/antiandrogens is not affected by the study. During the course of the study no invasive interventions are being performed.

Use of Dapagliflozin in Primary Prevention of Cardiotoxicity of Anthracycline Chemotherapy in Breast Cancer Patients

The goal of this randomized, double-blind, placebo-controlled clinical trial is to determine whether dapagliflozin, a sodium-glucose cotransporter-2 (SGLT-2) inhibitor, can help prevent anthracycline-induced cardiotoxicity caused by anthracycline chemotherapy in adult women with breast cancer receiving (neo)adjuvant treatment. The main questions the study aims to answer are: i) Does dapagliflozin reduce the decline in left ventricular function (measured by LVEF, GLS, and myocardial work) during and after anthracycline therapy? ii) Does dapagliflozin lessen the deteriorating effect of chemotherapy on endothelial function and arterial stiffness? iii) Does dapagliflozin effect levels of cardiac injury and inflammation biomarkers (e.g., hs-troponin T, NT-proBNP, ST-2, GDF-15, galectin-3, IL-6, MPO)? Researchers will compare dapagliflozin 10 mg daily with placebo to see whether those receiving dapagliflozin experience less heart and vascular impairment during treatment. Participants will: * Take either dapagliflozin or placebo once daily during anthracycline chemotherapy. * Undergo heart and vascular ultrasound, and a 6-minute walk test before chemotherapy and again at 24 and 52 weeks. * Provide blood samples before, during and after chemotherapy to measure cardiac biomarkers. * Complete multiple questionnaires on quality of life.

Vitamin K2 Supplementation in Adult Episodic Migraine

Migraine is a debilitating illness and a major cause of disability in the world. It is highly prevalent, especially among women. Vitamin supplementation is a potential therapeutic option for migraines that remains largely under-explored. Several studies have shown that people with migraine tend to have higher arterial stiffness than people without migraine. Vitamin K2 deficiency is an important mediator of arterial stiffness and calcification due to decreased carboxylation of matrix Gla protein (MGP). Supplementation reverses these changes and improves vascular health in patients with end stage renal disease according to previous studies. Therefore, vitamin K2 supplementation could serve a potential role in migraine patients. The purpose of the study is to test the effect of vitamin K2 on decreasing the frequency of migraine attacks and decreasing arterial stiffness. The population will be recruited from the neurology clinic at LAU Medical Center-Rizk Hospital and will constitute of adult patients. They will be randomized to receive either the supplement of vitamin K2 or a placebo for the duration of 6 months. Laboratory tests and arterial stiffness measurements will be done at the beginning, middle, and at the end of the study for comparison.

Fisetin to Improve Vascular Function in Older Adults

This is a pilot clinical trial to test the efficacy of intermittent treatment with the flavonoid compound fisetin for improving vascular endothelial function and reducing aortic stiffness in older adults. This trial will also determine the potential mechanisms by which fisetin may improve vascular function, including by decreasing mitochondrial oxidative stress, cellular senescence and senescence-associated secretory phenotype (SASP) factors in circulation. Lastly, safety, tolerability and adherence of fisetin treatment will be assessed.

Effect of Equol Supplementation on Arterial Stiffness and Cognition in Healthy Volunteers

The ACE Trial, funded by the National Institute on Ageing/National Institutes of Health (NIH), is a multicenter clinical trial. The ACE Trial will determine if taking the dietary supplement Equol could slow the progression of stiffening of the arteries, small blood vessel disease in the brain and memory decline. Equol is a soy-based supplement that has plant estrogen-like compounds in it. Equol is a metabolite of soy isoflavone. Our studies in Japan and other studies suggest that Equol may slow mechanisms related to memory decline. No previous studies in the United States have tested the effect of Equol on these mechanisms or memory decline. Supplementation of Equol in the ACE Trial is approved by the Food and Drug Administration (FDA). Researchers at the University of Pittsburgh, Pittsburgh, Pennsylvania, Wake Forest University, Winston-Salem, North Carolina, and Emory University, Atlanta, Georgia, are recruiting participants. The ACE Trial will ask participants to complete 7 clinic visits over a two-year period. The participants are asked to take Equol tablets daily for 24 months. Clinic procedures include Pulse Wave Velocity (to measure arterial stiffness), Magnetic Resonance Imaging (MRI) of the brain and tests of awareness and thinking.

Diurnal BP Patterns in Those at Increased Risk of CVD

In health, blood pressure (BP) falls at night by \>10% compared with day-time values. This natural dipping pattern is important as without it there is an increased risk of cardiovascular disease (CVD). Recent evidence suggests that chronotherapy (taking anti-hypertensive medication at bedtime instead of in the morning) may enhance nocturnal BP dipping and reduce the risk of CVD events. There is therefore an urgent need to characterise diurnal BP patterns in patients who may be at risk of reduced nocturnal dipping in order to maximise protective therapy in all those who would benefit. Similarly, it has previously been demonstrated that increased arterial stiffness is associated with increased CVD risk, however little is known about whether loss of diurnal variations in arterial stiffness confer addition risk. Kidney disease is independently associated with increased CVD events, but the exact makeup of this risk is not clear. Within this heterogenous cohort several very distinct groups exist including those with acute kidney injury (AKI), chronic kidney disease (CKD), inflammatory conditions like small vessel vasculitis (SVV), and those who have either donated or received a kidney transplant. Diurnal BP and arterial stiffness patterns within these patient groups are not well characterised. The investigators will recruit patients at increased risk of CVD from the Royal Infirmary of Edinburgh Renal and Vasculitis Clinics. Participants will undergo 24-hour ambulatory BP and arterial stiffness measurement in conjunction with day- and night-time blood and urine sampling on two separate occasions. This study aims to characterise diurnal patterns of BP and arterial stiffness in patients at increased risk of CVD and compare findings with healthy controls. In doing so, the investigators aim to allow more targeted CVD risk reduction strategies and improve long-term patient outcomes.

Effect of High-intensity Interval Training Combined With DASH Diet on Arterial Stiffness in Hypertensive Patients

Cardiovascular disease (CVD) is one of the leading causes of mortality worldwide and a major risk factor for morbidity worldwide . It is necessary to reduce the incidence and risk factors of CVD, as physical activity is known to reduce mortality from CVD. Arterial stiffness and hypertension are closely related in pathophysiology. Chronic high blood pressure (BP) can lead to arterial wall damage by mechanical stress, endothelial dysfunction, increased inflammation, oxidative stress, and renin-angiotensin-aldosterone system (RAAS) activation. HIIT has been shown to be equally or even better at stimulating health benefits than moderate-intensity continuous training (MICT) and is considered a time-saving aerobic exercise for reducing arterial stiffness in HTN patients

Risk Markers of Arterial Aging. The Paris Prospective Study III-2

The main objectives of PPS3-2 are (i) to describe the dynamics of vascular aging and baroreflex sensitivity 12 to 16 years a part, (ii) to identify their determinants, and (iii) to quantify the subsequent risk of cardiovascular diseases.

High-Intensity Exercise to Combat Vascular and Cognitive Dysfunction in Adults With HIV

This is a single site, randomized exercise trial with individuals at least 50 years of age living with HIV who experience suboptimal cognition. The overall goals of this proposal are to determine whether 16 weeks of structured high-intensity interval training (HIIT) can overcome vascular and cognitive impairments (Aim 1) to a greater extent than continuous moderate exercise. Additionally, investigator will seek to identify barriers to engagement in exercise and the participants' perceptions of the study and exercise interventions (Aim 2). This study will enroll 60 participants in Birmingham, Alabama. Data collection will occur at each visit, with baseline data collected at the initial visit with a 3-month follow-up occurring following completion of the intervention.

Cardiovascular Risk Factors and Physical Activity in Chronic Kidney Patients on Peritoneal Dialysis

The objective of this study was to examine the association between cardiovascular risk factors and physical activity parameters in patients with chronic kidney disease who are treated with peritoneal dialysis.

Early Detection of Long-term Diabetic Complications in Children and Adolescents With Type 1 Diabetes

Aims: To investigate early markers of long-term diabetic complications and the association to an extended glucose metabolic profile comprising glucose control (current and past), glucose variability and insulin sensitivity in children and adolescents with type 1 diabetes (T1D). Background: Most Danish children and adolescents with T1D do not achieve their metabolic target and are at increased risk of developing long-term diabetic complications, reducing their life expectancy and increase their morbidity rate. Hence, improved metabolic control, a better understanding of what optimal metabolic control means, combined with detailed monitoring of the first markers of long-term complications and their reversibility or lack thereof are needed. Methods: A prospectivel study of 400 children, aged 6-18 years old, with T1D\>12 months. Early markers of long-term diabetic complications will be investigated as arterial stiffness, nerve dysfunction and nephropathy. Data on T1D onset, duration, treatment modality, self-monitoring-blood-glucose profiles, growth, weight, and pubertal status will be collected. Blood sampling will include routine tests and markers of glucose, lipid, bone, and gastrointestinal metabolism. DXA-scan, Fibroscan, bone-age, eye-examination and physical activity will be measured. Data on retrospective glucose- and lipid-profiles will be collected. The children will be offered a followup every 5 years for the next two decades. Perspectives: This study provides novel insight into the frequency of early markers of long-term diabetic complications and its association to the interplay of the pancreas, adipose, gastrointestinal and bone metabolic axis. Which can assist in identifying subgroups of children and adolescents requiring earlier in-depth screening for early markers of long-term diabetic complications, for putative interventions for prevention, hence reducing morbidity and mortality in T1D.

SCAPIS 2 Cardio - Vibrometer Based Pulse Wave Analysis and CVD Risk Assessment

This clinical investigation will evaluate a novel contactless technology for assessing arterial stiffness and pulse wave characteristics and explore its potential in assessment of coronary artery disease, aortic stenosis and heart failure, in a population-based sample aged 58-72 years. It will be the first in clinical setting, pilot stage, observational investigation to evaluate the clinical safety, performance and diagnostic accuracy of Cardio P4, a laser-doppler vibrometry (LDV) and microwave radar-based device.

Prebiotic Effects of California Grapes on Gut Health and Cardiometabolic Health in Overweight Men and Women

The goal of this clinical trial is to assess the impact of table grape consumption on gut microbiome, intestinal permeability, systemic inflammation, and vascular function in healthy overweight men and women aged 45-70 years. The main questions it aims to answer are: * Does daily grape intake alter intestinal microbiome composition and intestinal permeability? * Are changes in gut microbiota and intestinal permeability correlated with changes in cardiometabolic risk factors (inflammation, vascular function, lipid profiles)? * Does response to grape intake on gut microbiota, intestinal permeability, cardiometabolic and inflammatory markers differ between men and women? * Are metabolic pathways modified by grape consumption able to explain the link between gut health and cardiometabolic factors? Researchers will compare freeze-dried grape powder to placebo powder to see if grape powder improves cardiometabolic risk factors. Participants will * Consume the powder dissolved in water twice daily for 3 weeks * Follow their usual diet, modified to limit polyphenol-rich foods * Visit the clinic at the beginning and end of the intervention for vascular measurements and blood sample collection * Complete a 3-day 24-hour dietary recall and collect stool sample before each visit

Early Prediction of Preeclampsia Using arteriaL Stiffness in High-risk prEgnancies

Despite advances in obstetric care, preeclampsia (PE) remains the leading cause of maternal death and disability in both developed and developing countries, contributing to over 70,000 maternal and 500,000 fetal deaths annually worldwide. PULSE was designed using a preventative medicine approach, focusing on improving early detection of PE as opposed to managing symptoms after onset. The study aims to uncover the earliest possible signs of PE using a combination of novel clinical tools and established diagnostic techniques to better identify, track, and manage high risk pregnant women. Specifically, PULSE will be examining the incorporation of a non-invasive test for the measurement of arterial stiffness, which has been shown to be predictive of hypertensive disorders. This test, in combination with a wide range of blood biomarkers, detailed ultrasound imaging, and a comprehensive battery of physical and mental health questionnaires, represents the largest, most comprehensive preventative PE study to date. The results of this work has the potential to revolutionize the way PE and other hypertensive disorders of pregnancy are managed and treated and can serve to inform the design of future preventative clinical research studies.

Shenfu Injection Modulates Carotid Elasticity in Septic Shock

What is this study about? We are studying whether Shenfu Injection (a traditional Chinese herbal medicine) can help improve blood vessel health in patients with septic shock-a severe complication of infections that can damage blood vessels and organs. Specifically, we want to see if this treatment makes the carotid artery (a major neck blood vessel) more flexible and resilient, which may support recovery. Who can join? Adults (18 years or older) diagnosed with septic shock by their doctors. Patients whose doctors plan to use Shenfu Injection as part of their treatment. Patients who agree to participate and sign a consent form. Who cannot join? Patients with severe heart conditions, advanced organ failure, or major neck artery disease. Pregnant or breastfeeding women. Those unable to complete the study procedures. What will happen during the study? Safe and Pain-Free Tests: Ultrasound scans: A non-invasive imaging method will be used to measure the flexibility and blood flow of your neck artery. Advanced imaging technology: A special ultrasound technique (called speckle tracking) will take detailed pictures of your artery's movement during heartbeat cycles. Timing of Tests: Scans will be done before receiving Shenfu Injection and 1, 2, 3 hours after the injection, plus 1 hour after treatment ends. Other Data Collection: Blood tests to check inflammation and organ function. Recording your health status (e.g., blood pressure, heart rate) and recovery progress (e.g., time in the Intensive Care Unit (ICU), survival rates). What are the benefits and risks? Benefits: This study may help doctors better understand how Shenfu Injection works and improve future care for septic shock patients. Risks: The ultrasound scans are routine, safe, and painless. There is no extra risk beyond standard hospital care. Your Rights and Safety Voluntary Participation: You can withdraw at any time without affecting your treatment. Ethical Approval: This study is reviewed and approved by the hospital's ethics committee. Privacy: Your personal information and test results will be kept confidential.

The Effect of Cytisine Treatment for Smoking Cessation on Cardiovascular Function in Adult Smokers

Introduction: Pharmacological interventions can enhance smoking cessation success and long-term abstinence. Cytisine, a plant derived alkaloid, is a selective partial agonist at alpha-4 beta-2 nicotinic acetylcholine receptors, which are crucial in nicotine dependence. Aim of the Study The primary objective of this observational study is to evaluate the efficacy of cytisine in a standard 25-day dosing regimen among adult smokers and users of alternative nicotine products (e-cigarettes or heated tobacco). The study will assess the impact of cytisine on cardiovascular function, including arterial stiffness, cardiac deformation, and endothelial glycocalyx integrity. The secondary aim is to determine relapse rates post-treatment, treatment side effects, and new cardiovascular events during the treatment period and at six-month follow-up. Materials and Methods: This observational study will recruit smokers visiting the smoking cessation unit at the 2nd Department of Cardiology, Attikon University Hospital, Athens. All participants will receive counseling and treatment from the attending physician. A minimum of 200 participants will be enrolled, categorized into: • At least 50 receiving cytisine in the standard dosing regimen: Days 1-3: 1 tablet every 2 hours (6 tablets daily) Days 4-12: 1 tablet every 2.5 hours (5 tablets daily) Days 13-16: 1 tablet every 3 hours (4 tablets daily) Days 17-20: 1 tablet every 5 hours (3 tablets daily) Days 21-25: 1-2 tablets daily * At least 50 receiving nicotine replacement therapy * At least 50 receiving prolonged cytisine therapy (3 mg, three times daily for 12 weeks) * At least 50 who do not intend to quit smoking (control group) Assessments will be conducted at baseline, one month, and six months post-recruitment. The following measurements will be performed: A. Arterial Stiffness: Pulse wave velocity (cf-PWV) using the Complior device to measure arterial stiffness, Augmentation index and pulse wave velocity using the Arteriograph device via brachial artery cuff. B. Endothelial Glycocalyx Integrity: Perfused boundary region (PBR) assessment of sublingual microvasculature using a Sidestream Dark Field (SDF) camera. C. Cardiac Function: Left ventricular ejection fraction (LVEF), myocardial strain (GLS), and myocardial work assessment via speckle-tracking echocardiography (Echopac 203, GE Horten Norway).The investigators will also calculate myocardial work (MW) using pressure-strain loop analysis. D. Oxidative Stress: Plasma malondialdehyde (MDA) and protein carbonyl (PC) levels measured via spectrophotometry. E. Smoking Cessation Monitoring: Exhaled carbon monoxide (CO) measured using a commercial device (Smokelyzer, Bedfont Scientific Ltd.). This study aims to provide valuable insights into cytisine's effectiveness in smoking cessation and its impact on cardiovascular health.