# Dissecting heterogeneity of excessive daytime sleepiness and impact on cardiovascular diseases

> **NIH NIH R01** · BRIGHAM AND WOMEN'S HOSPITAL · 2024 · $402,750

## Abstract

ABSTRACT
Excessive daytime sleepiness (EDS) affects 10-20% of the population and is associated with
cardiovascular diseases (CVD) and mortality. Emerging data suggest that targeting EDS may
provide a novel intervention for improving CVD. However, findings are limited by self-reported
data and heterogeneity. There is a need to dissect and understand the underlying drivers of EDS
subtypes, and to determine whether there are subtypes causally related to CVD and potentially
modifiable. Our recent work identified two subtypes of EDS – sleep propensity (SP; characterized
by objectively measured long sleep duration, high efficiency, and less fragmentation) and sleep
fragmentation (SF; short sleep duration and low efficiency). Each of them is common in the
population, associated with adverse cardiovascular outcomes and different genetic backgrounds.
We hypothesize that SP is a novel sleep phenotype that reflects a property of the need of staying
asleep; dissecting EDS into SP and SF subtypes will facilitate identification of genetic and
physiological mechanisms for EDS, and improve understanding of pleiotropic or causal
associations with CVD risk. In order to test these hypotheses, we will leverage macro- and micro-
sleep architecture measurements, genomics, and other -omics data in population-based cohorts.
We will address the following specific aims: 1) To identify demographic, behavioral, clinical and
neurophysiological factors (assessed by actigraphy and electroencephalography) for SP and SF,
and refine classification of EDS subtypes if needed; 2) To identify genetic variants and molecular
pathways associated with EDS subtypes and generate robust polygenetic risk score for risk
stratification; 3) To systematically evaluate the causal or non-causal associations between EDS
subtypes and CVD traits; 4) To identify the modification effect of each EDS subtype on genetic
susceptibility of CVD using gene-environment interaction analyses. This work will advance our
understanding of the heterogeneity of EDS, reveal biological mechanisms and pathways linking
to CVD, and provide information that will guide clinical and public health interventions as well as
provide directions for future laboratory research.

## Key facts

- **NIH application ID:** 10812409
- **Project number:** 5R01HL153814-04
- **Recipient organization:** BRIGHAM AND WOMEN'S HOSPITAL
- **Principal Investigator:** Heming Wang
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $402,750
- **Award type:** 5
- **Project period:** 2021-04-20 → 2026-03-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10812409

## Citation

> US National Institutes of Health, RePORTER application 10812409, Dissecting heterogeneity of excessive daytime sleepiness and impact on cardiovascular diseases (5R01HL153814-04). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/10812409. Licensed CC0.

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