Estimating blood pressure trends and the nocturnal dip from photoplethysmography.
Physiol Meas
; 40(2): 025006, 2019 02 26.
Article
in En
| MEDLINE
| ID: mdl-30699397
ABSTRACT
OBJECTIVE:
Evaluate a method for the estimation of the nocturnal systolic blood pressure (SBP) dip from 24 h blood pressure trends using a wrist-worn photoplethysmography (PPG) sensor and a deep neural network in free-living individuals, comparing the deep neural network to traditional machine learning and non-machine learning baselines.APPROACH:
A wrist-worn PPG sensor was worn by 106 healthy individuals for 226 d during which 5111 reference values for blood pressure (BP) were obtained with a 24 h ambulatory BP monitor and matched with the PPG sensor data. Features based on heart rate variability and pulse morphology were extracted from the PPG waveforms. Long- and short term memory (LSTM) networks, dense networks, random forests and linear regression models were trained and evaluated in their capability of tracking trends in BP, as well as the estimation of the SBP dip. MAINRESULTS:
Best performance for estimating the SBP dip were obtained with a deep LSTM neural network with a root mean squared error (RMSE) of 3.12 [Formula see text] 2.20 [Formula see text] mmHg and a correlation of 0.69 [Formula see text]. This dip was derived from trend estimates of BP which had an RMSE of 8.22 [Formula see text] 1.49 mmHg for systolic and 6.55 [Formula see text] 1.39 mmHg for diastolic BP (DBP). While other models had similar performance for the tracking of relative BP, they did not perform as well as the LSTM for the SBP dip.SIGNIFICANCE:
The work provides first evidence for the unobtrusive estimation of the nocturnal SBP dip, a highly prognostic clinical parameter. It is also the first to evaluate unobtrusive BP measurement in a large data set of unconstrained 24 h measurements in free-living individuals and provides evidence for the utility of LSTM models in this domain.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Blood Pressure Determination
/
Circadian Rhythm
/
Photoplethysmography
Type of study:
Prognostic_studies
/
Risk_factors_studies
Limits:
Adolescent
/
Adult
/
Female
/
Humans
/
Male
/
Middle aged
Language:
En
Journal:
Physiol Meas
Journal subject:
BIOFISICA
/
ENGENHARIA BIOMEDICA
/
FISIOLOGIA
Year:
2019
Document type:
Article
Affiliation country:
Netherlands
Publication country:
ENGLAND
/
ESCOCIA
/
GB
/
GREAT BRITAIN
/
INGLATERRA
/
REINO UNIDO
/
SCOTLAND
/
UK
/
UNITED KINGDOM