Autonomic Nervous System Imbalance, Blood Coagulation Disorders, Blood Pressure, Inflammation, Vasoconstriction
Conditions
Keywords
Heart rate variability, Blood pressure, Circulating biomarkers, Respirator, Fine particulate matter
Brief summary
An intervention study to assess the short-term cardiovascular effects of reducing personal air pollution exposure by wearing particulate filtering respirators.
Detailed description
A group of healthy adult college students fulfilling the recruitment criteria were randomly divided into two sub-groups. One sub-group weared the particulate filtering respirators for 2 continuous days during which the respirator was required to wear as much as possible both indoor and outdoor. The other group acted as normal at the same time. The measurements on health effects including heart rate varibility, blood pressure, circulating biomarkers as well as the ambient air pollution were performed in both groups during the intervention period. After a 3-week rest period,the two groups interchanged their roles of wearing the respirator or not. The same measurements of both health effects indicators and ambient air pollution were repeated.
Interventions
BEHAVIORALWear respirator
Healthy adult subjects wore the particulate filtering respirators for continuous 48 hours as much as possible both indoor and outdoor.
Sponsors
Fudan University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
PREVENTION
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 35 Years
Healthy volunteers
Yes
Inclusion criteria
* Equal to or older than 18 years old, * No history of smoking and alcohol addiction. * No chronic diseases,such as hypertension,diabetes,chronic obstructive pulmonary disease or other respiratory/cardiovascular diseases reported by volunteers. * No respiratory or allergic diseases, like asthma, rhinitis,or other allergic diseases.
Exclusion criteria
* Current smokers * Chronic drug use due on cardiovascular or respiratory diseases
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Heart Rate Variability-LF Power,HF Power,VLF Power | up to 24 hours | HRV is a quantitative health marker reflecting how the autonomic nervous system modulates the sinoatrial node in the heart and HRV has therefore been widely used to estimate cardiac autonomic function and control. Subjects were attached with Holter monitor on the 2nd day in each of the 48-hr intervention period.A total of 8 parameters of HRV were analyzed including 4 time-domain indices and 4 frequency-domain indices. Frequency domain methods assign bands of frequency and then count the number of NN intervals that match each band. The bands are typically high frequency (HF) from 0.15 to 0.4 Hz, low frequency (LF) from 0.04 to 0.15 Hz, and the very low frequency (VLF) from 0.0033 to 0.04 Hz. Parasympathetic activity is a major contributor to the HF component. More problematic is the interpretation of the LF component, which was considered by some as a marker of sympathetic modulation but is now known to include both sympathetic and vagal influences. |
| Blood Pressure | up to 24 hours | The blood pressure were measured by automatic blood pressure monitor during the intervention study. |
| Heart Rate Variability-SDNN,SDANN, rMSSD | Up to 24 hours | HRV is a quantitative health marker reflecting how the autonomic nervous system modulates the sinoatrial node in the heart and HRV has therefore been widely used to estimate cardiac autonomic function and control.A total of 8 parameters of HRV were analyzed including 4 time-domain indices and 4 frequency-domain indices. Subjects were attached with Holter monitor on the 2nd day in each of the 48-hr intervention period. Heart rate and heart automatic function indices including the standard deviation of the normal-to-normal interval(SDNN),the standard deviation of the average NN intervals calculated over short periods(SDANN), the root mean square of the successive differences(rMSSD) were automatically recorded during the intervention. |
| Heart Rate Variability-LF/HF | Up to 24 hours | HRV is a quantitative health marker reflecting how the autonomic nervous system modulates the sinoatrial node in the heart and HRV has therefore been widely used to estimate cardiac autonomic function and control. Subjects were attached with Holter monitor on the 2nd day in each of the 48-hr intervention period.A total of 8 parameters of HRV were analyzed including 4 time-domain indices and 4 frequency-domain indices. Frequency domain methods assign bands of frequency and then count the number of NN intervals that match each band. The bands are typically high frequency (HF) from 0.15 to 0.4 Hz, low frequency (LF) from 0.04 to 0.15 Hz. Parasympathetic activity is a major contributor to the HF component. More problematic is the interpretation of the LF component, which was considered by some as a marker of sympathetic modulation but is now known to include both sympathetic and vagal influences. |
| Heart Rate Variability-pNN50 | Up to 24 hours | HRV is a quantitative health marker reflecting how the autonomic nervous system modulates the sinoatrial node in the heart and HRV has therefore been widely used to estimate cardiac autonomic function and control.A total of 8 parameters of HRV were analyzed including 4 time-domain indices and 4 frequency-domain indices. Subjects were attached with Holter monitor on the 2nd day in each of the 48-hr intervention period. Heart rate and heart automatic function indices including the proportion of successive normal NN intervals differing by more than 50 ms in the total number of NNs（pNN50） were automatically recorded during the intervention. |
| Circulating Biomarkers--Fibrinogen，vWF | Up to 24 hours | At the end of each intervention, participants were asked to rest in a quiet room for half an hour. Peripheral venous blood samples were collected and centrifuged immediately. The serum were collected and stored at -80℃ within 30 minutes to minimize the in-vitro changes in biomarker proteins. Fibrinogen and von Willebrand factor(vWF) were measured by using the Millipore MILLIPLEX MAP human cytokine/chemokine kit (Millipore Corp., Billerica, Massachusetts) |
| Circulating Biomarkers--P- Selectin,VCAM-1 | Up to 24 hours | At the end of each intervention, participants were asked to rest in a quiet room for half an hour. Peripheral venous blood samples were collected and centrifuged immediately. The serum were collected and stored at -80℃ within 30 minutes to minimize the in-vitro changes in biomarker proteins. P- selectin,VCAM-1(vascular cell adhesion molecule-1) were measured by using the Millipore MILLIPLEX MAP human cytokine/chemokine kit (Millipore Corp., Billerica, Massachusetts) |
| Circulating Biomarkers--ET-1 | Up to 24 hours | At the end of each intervention, participants were asked to rest in a quiet room for half an hour. Peripheral venous blood samples were collected and centrifuged immediately. The serum were collected and stored at -80℃ within 30 minutes to minimize the in-vitro changes in biomarker proteins. Endothelin-1(ET-1) was using enzyme-linked immunosorbent assays. |
Countries
China
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| All Study Participants The recruited healthy subjects were randomly allocated into two groups. In the first intervention period, this group wore respirator for 2 continuous days including a 2-hour walking along the streets on the 2nd day along a fixed route. After a 2-week rest period, the 2nd intervention period started and they changed to not wearing the respirator but participated all the measurements of health indicators and ambient air pollution for 2 continuous days including the 2-hour walking along the streets on the 2nd day along the same fixed route. The same protocol on the measurements of health indicators and ambient air pollution was applied in the 1st intervention and 2nd intervention period.
Wear respirator: Healthy adult subjects wore the particulate filtering respirators for continuous 48 hours as much as possible both indoor and outdoor. | 24 |
| Total | 24 |
Baseline characteristics
| Characteristic | All Study Participants |
|---|---|
| Age, Categorical <=18 years | 0 Participants |
| Age, Categorical >=65 years | 0 Participants |
| Age, Categorical Between 18 and 65 years | 24 Participants |
| Age, Continuous | 23 years STANDARD_DEVIATION 2 |
| BMI | 22 kg/m^2 STANDARD_DEVIATION 4 |
| diastolic pressure | 70 mmHg STANDARD_DEVIATION 5 |
| Region of Enrollment China | 24 participants |
| Sex: Female, Male Female | 11 Participants |
| Sex: Female, Male Male | 13 Participants |
| systolic pressure | 108 mmHg STANDARD_DEVIATION 8 |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 0 / 24 | 0 / 24 |
| serious Total, serious adverse events | 0 / 24 | 0 / 24 |
Outcome results
Primary
Blood Pressure
The blood pressure were measured by automatic blood pressure monitor during the intervention study.
Time frame: up to 24 hours
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Wear Respirator | Blood Pressure | systolic blood pressure | 107.3 mmHg | Standard Deviation 8 |
| Wear Respirator | Blood Pressure | diastolic blood pressure | 70.0 mmHg | Standard Deviation 5 |
| Not Wear Respirator | Blood Pressure | systolic blood pressure | 109.0 mmHg | Standard Deviation 7.4 |
| Not Wear Respirator | Blood Pressure | diastolic blood pressure | 70.8 mmHg | Standard Deviation 4.8 |
p-value: <0.05Paired t-test,2 sided
Primary
Circulating Biomarkers--ET-1
At the end of each intervention, participants were asked to rest in a quiet room for half an hour. Peripheral venous blood samples were collected and centrifuged immediately. The serum were collected and stored at -80℃ within 30 minutes to minimize the in-vitro changes in biomarker proteins. Endothelin-1(ET-1) was using enzyme-linked immunosorbent assays.
Time frame: Up to 24 hours
| Arm | Measure | Value (GEOMETRIC_MEAN) | Dispersion |
|---|---|---|---|
| Wear Respirator | Circulating Biomarkers--ET-1 | 109.9 pg/ml | Standard Deviation 1.6 |
| Not Wear Respirator | Circulating Biomarkers--ET-1 | 121.5 pg/ml | Standard Deviation 1.6 |
Primary
Circulating Biomarkers--Fibrinogen，vWF
At the end of each intervention, participants were asked to rest in a quiet room for half an hour. Peripheral venous blood samples were collected and centrifuged immediately. The serum were collected and stored at -80℃ within 30 minutes to minimize the in-vitro changes in biomarker proteins. Fibrinogen and von Willebrand factor(vWF) were measured by using the Millipore MILLIPLEX MAP human cytokine/chemokine kit (Millipore Corp., Billerica, Massachusetts)
Time frame: Up to 24 hours
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) | Dispersion |
|---|---|---|---|---|
| Wear Respirator | Circulating Biomarkers--Fibrinogen，vWF | Fibrinogen | 2.5 µg/ml | Standard Deviation 1.3 |
| Wear Respirator | Circulating Biomarkers--Fibrinogen，vWF | vWF | 24.5 µg/ml | Standard Deviation 1.3 |
| Not Wear Respirator | Circulating Biomarkers--Fibrinogen，vWF | Fibrinogen | 2.5 µg/ml | Standard Deviation 1.3 |
| Not Wear Respirator | Circulating Biomarkers--Fibrinogen，vWF | vWF | 27.1 µg/ml | Standard Deviation 1.3 |
Primary
Circulating Biomarkers--P- Selectin,VCAM-1
At the end of each intervention, participants were asked to rest in a quiet room for half an hour. Peripheral venous blood samples were collected and centrifuged immediately. The serum were collected and stored at -80℃ within 30 minutes to minimize the in-vitro changes in biomarker proteins. P- selectin,VCAM-1(vascular cell adhesion molecule-1) were measured by using the Millipore MILLIPLEX MAP human cytokine/chemokine kit (Millipore Corp., Billerica, Massachusetts)
Time frame: Up to 24 hours
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) | Dispersion |
|---|---|---|---|---|
| Wear Respirator | Circulating Biomarkers--P- Selectin,VCAM-1 | P-selectin | 164.0 ng/ml | Standard Deviation 2 |
| Wear Respirator | Circulating Biomarkers--P- Selectin,VCAM-1 | VCAM-1 | 1480.3 ng/ml | Standard Deviation 1.5 |
| Not Wear Respirator | Circulating Biomarkers--P- Selectin,VCAM-1 | P-selectin | 200.3 ng/ml | Standard Deviation 1.5 |
| Not Wear Respirator | Circulating Biomarkers--P- Selectin,VCAM-1 | VCAM-1 | 1808.0 ng/ml | Standard Deviation 1.6 |
Primary
Heart Rate Variability-LF/HF
HRV is a quantitative health marker reflecting how the autonomic nervous system modulates the sinoatrial node in the heart and HRV has therefore been widely used to estimate cardiac autonomic function and control. Subjects were attached with Holter monitor on the 2nd day in each of the 48-hr intervention period.A total of 8 parameters of HRV were analyzed including 4 time-domain indices and 4 frequency-domain indices. Frequency domain methods assign bands of frequency and then count the number of NN intervals that match each band. The bands are typically high frequency (HF) from 0.15 to 0.4 Hz, low frequency (LF) from 0.04 to 0.15 Hz. Parasympathetic activity is a major contributor to the HF component. More problematic is the interpretation of the LF component, which was considered by some as a marker of sympathetic modulation but is now known to include both sympathetic and vagal influences.
Time frame: Up to 24 hours
| Arm | Measure | Value (GEOMETRIC_MEAN) | Dispersion |
|---|---|---|---|
| Wear Respirator | Heart Rate Variability-LF/HF | 1.4 ratio | Standard Deviation 0.3 |
| Not Wear Respirator | Heart Rate Variability-LF/HF | 1.5 ratio | Standard Deviation 0.3 |
Primary
Heart Rate Variability-LF Power,HF Power,VLF Power
HRV is a quantitative health marker reflecting how the autonomic nervous system modulates the sinoatrial node in the heart and HRV has therefore been widely used to estimate cardiac autonomic function and control. Subjects were attached with Holter monitor on the 2nd day in each of the 48-hr intervention period.A total of 8 parameters of HRV were analyzed including 4 time-domain indices and 4 frequency-domain indices. Frequency domain methods assign bands of frequency and then count the number of NN intervals that match each band. The bands are typically high frequency (HF) from 0.15 to 0.4 Hz, low frequency (LF) from 0.04 to 0.15 Hz, and the very low frequency (VLF) from 0.0033 to 0.04 Hz. Parasympathetic activity is a major contributor to the HF component. More problematic is the interpretation of the LF component, which was considered by some as a marker of sympathetic modulation but is now known to include both sympathetic and vagal influences.
Time frame: up to 24 hours
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) | Dispersion |
|---|---|---|---|---|
| Wear Respirator | Heart Rate Variability-LF Power,HF Power,VLF Power | low frequency(LF) power | 899.4 ms^2 | Standard Deviation 601.3 |
| Wear Respirator | Heart Rate Variability-LF Power,HF Power,VLF Power | high frequency(HF) power | 519.7 ms^2 | Standard Deviation 371 |
| Wear Respirator | Heart Rate Variability-LF Power,HF Power,VLF Power | very low frequency(VLF) power | 1684.6 ms^2 | Standard Deviation 875.7 |
| Not Wear Respirator | Heart Rate Variability-LF Power,HF Power,VLF Power | low frequency(LF) power | 838.5 ms^2 | Standard Deviation 562.4 |
| Not Wear Respirator | Heart Rate Variability-LF Power,HF Power,VLF Power | high frequency(HF) power | 416.6 ms^2 | Standard Deviation 296.6 |
| Not Wear Respirator | Heart Rate Variability-LF Power,HF Power,VLF Power | very low frequency(VLF) power | 1623.1 ms^2 | Standard Deviation 1006.5 |
Comparison: Paired Student's t tests were used in the absence and presence of wearing respirators. HRV was log-transformed before regression analyses. Linear mixed-effect models were applied to investigate the effects of wearing respirators. Age, sex, body mass index, PM2.5 concentration, 48-h mean temperature and 48-h mean humidity were introduced into the model as fixed-effect terms. At last, we incorporated random-effect intercepts for subjects to account for correlations between repeated measurements.p-value: <0.05Paired t-test,2 sided
Primary
Heart Rate Variability-pNN50
HRV is a quantitative health marker reflecting how the autonomic nervous system modulates the sinoatrial node in the heart and HRV has therefore been widely used to estimate cardiac autonomic function and control.A total of 8 parameters of HRV were analyzed including 4 time-domain indices and 4 frequency-domain indices. Subjects were attached with Holter monitor on the 2nd day in each of the 48-hr intervention period. Heart rate and heart automatic function indices including the proportion of successive normal NN intervals differing by more than 50 ms in the total number of NNs（pNN50） were automatically recorded during the intervention.
Time frame: Up to 24 hours
| Arm | Measure | Value (GEOMETRIC_MEAN) | Dispersion |
|---|---|---|---|
| Wear Respirator | Heart Rate Variability-pNN50 | 24.0 percentage of ms | Standard Deviation 9.9 |
| Not Wear Respirator | Heart Rate Variability-pNN50 | 20.5 percentage of ms | Standard Deviation 10.5 |
Primary
Heart Rate Variability-SDNN,SDANN, rMSSD
HRV is a quantitative health marker reflecting how the autonomic nervous system modulates the sinoatrial node in the heart and HRV has therefore been widely used to estimate cardiac autonomic function and control.A total of 8 parameters of HRV were analyzed including 4 time-domain indices and 4 frequency-domain indices. Subjects were attached with Holter monitor on the 2nd day in each of the 48-hr intervention period. Heart rate and heart automatic function indices including the standard deviation of the normal-to-normal interval(SDNN),the standard deviation of the average NN intervals calculated over short periods(SDANN), the root mean square of the successive differences(rMSSD) were automatically recorded during the intervention.
Time frame: Up to 24 hours
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) | Dispersion |
|---|---|---|---|---|
| Wear Respirator | Heart Rate Variability-SDNN,SDANN, rMSSD | SDNN | 177.5 ms | Standard Deviation 29.9 |
| Wear Respirator | Heart Rate Variability-SDNN,SDANN, rMSSD | SDANN | 160.7 ms | Standard Deviation 28.9 |
| Wear Respirator | Heart Rate Variability-SDNN,SDANN, rMSSD | rMSSD | 49.0 ms | Standard Deviation 13.3 |