Project Grant F31HL181943

EVALUATING THE ASSOCIATION OF SLEEP VARIABILITY ON MEASURES OF CARDIOVASCULAR HEALTH IN FEMALES AT DIFFERENT STAGES OF LIFE - ABSTRACT: THE PROPOSED RESEARCH AIMS TO INVESTIGATE THE RELATIONSHIP BETWEEN SLEEP VARIABILITY AND CARDIOVASCULAR (CV) HEALTH MARKERS IN PRE- AND POSTMENOPAUSAL FEMALES. SLEEP VARIABILITY, CHARACTERIZED BY IRREGULAR SLEEP DURATION AND TIMING, IS A RECOGNIZED RISK FACTOR FOR HYPERTENSION (HTN) AND CARDIOVASCULAR DISEASE (CVD). HISTORICALLY, THERE HAS BEEN A LACK OF FEMALE REPRESENTATION IN SLEEP AND CIRCADIAN RESEARCH, WITH MAJORITY OF RESEARCH FOCUSED ON MALES AND MIXED-GENDER SAMPLES, DESPITE EVIDENCE INDICATING SEX DIFFERENCES IN CIRCADIAN RHYTHMS AND SLEEP HEALTH. CIRCADIAN RHYTHMS ARE ENDOGENOUS PATTERNS THAT CONTROL A RANGE OF CV PROCESS SUCH AS, BLOOD PRESSURE (BP) AND VASCULAR FUNCTION ACROSS AN APPROXIMATE 24HR CYCLE. VARIABLE SLEEP PATTERNS CAN DISRUPT THESE INTERNAL RHYTHMS CAUSING ALTERATIONS IN 24-HR BP PATTERNS, VASCULAR FUNCTION, AND AUTONOMIC BP RESPONSES TO EXERCISE, WHICH ARE ALL ASSOCIATED WITH INCREASED RISK FOR CV EVENTS AND DISEASE. HOWEVER, SEX-AGGERATED DATA COMPLICATES THE INTERPRETATION AND GENERALIZATION OF PREVIOUS FINDINGS. THUS, INVESTIGATIONS TARGETED AT CHARACTERIZING THE IMPACT OF SLEEP VARIABILITY ON BP, VASCULAR FUNCTION, AND THE AUTONOMIC REGULATION OF BP ARE NEEDED, SPECIFICALLY IN FEMALES. THE OVERALL GOAL OF THIS F31 RESEARCH PROPOSAL IS TO INVESTIGATE HOW VARYING LEVELS OF SLEEP VARIABILITY RELATE TO 24-HR BP, VASCULAR FUNCTION, AND AUTONOMIC BP REGULATION IN FEMALES AT DIFFERENT STAGES OF LIFE. THIS PROPOSAL WILL FOSTER THE DEVELOPMENT OF NEW PROFICIENCIES AND TECHNICAL SKILLS IN AREAS OF CARDIAC BAROREFLEX SENSITIVITY VIA BEAT-BY-BEAT BP ASSESSMENT, AND MACRO- AND MICROVASCULAR FUNCTION VIA DOPPLER ULTRASOUND, TO SUPPORT THE INVESTIGATOR IN ACHIEVING THEIR LONG-TERM GOAL OF INVESTIGATING THE EFFECTS OF ACUTE AND CHRONIC SLEEP DISRUPTIONS ON CV HEALTH OUTCOMES. IN ORDER TO ACHIEVE THE OVERALL GOAL, THIS PROPOSAL ENCOMPASSES THREE SPECIFIC AIMS. AIM 1 SEEKS TO DETERMINE IF HIGH SLEEP VARIABILITY IS ASSOCIATED WITH DECREASED CARDIAC BAROREFLEX SENSITIVITY AND INCREASED BP REACTIVITY TO SYMPATHOEXCITATORY STIMULI IN PREMENOPAUSAL FEMALES. AIMS 2 AND 3 INVESTIGATE WHETHER HIGH SLEEP VARIABILITY IS LINKED TO REDUCED VASCULAR FUNCTION AND ELEVATED 24-HR BP PATTERNS IN BOTH PREMENOPAUSAL FEMALES AND POSTMENOPAUSAL FEMALES WITH HTN. THE CENTRAL HYPOTHESIS IS THAT INCREASED SLEEP VARIABILITY WILL BE ASSOCIATED WITH POOR CV HEALTH (I.E., 24-HR AMBULATORY BP, VASCULAR FUNCTION, AND AUTONOMIC REGULATION OF BP) IN DIFFERENT LIFE STAGES. THESE STUDIES ARE INNOVATIVE, IN THEIR USE OF NOVEL CONCEPTS RELATED TO SLEEP VARIABILITY AND CV HEALTH IN HEALTHY AND ELEVATED CVD RISK FEMALES, INCLUDING POSTMENOPAUSAL FEMALES WITH HTN. THE PROPOSED RESEARCH IS SIGNIFICANT BECAUSE IT WILL IMPROVE OUR UNDERSTANDING OF 1) THE UNDERLYING SYMPATHETIC REFLEXES ASSOCIATED WITH SLEEP VARIABILITY IN PREMENOPAUSAL FEMALES AND 2) ASSESS THE ASSOCIATION OF SLEEP VARIABILITY ON VASCULAR HEALTH IN PRE- AND POSTMENOPAUSAL FEMALES WITH HTN.