Circadian Disruption, Essential Arterial Hypertension
Conditions
Keywords
Arterial hypertension, Essential hypertension, Circadian disruption, Circadian rhythm, Sleep-wake rhythm, Actigraphy, Ambulatory blood pressure monitoring, 24-hour blood pressure, Cardiovascular risk Young adults
Brief summary
This prospective observational study will investigate whether circadian disruption is associated with higher blood pressure and a less favorable cardiovascular profile in young adults aged 18 to 45 years with essential arterial hypertension. Participants will undergo 14 days of wrist actigraphy using the CamNtech MotionWatch 8, 24-hour ambulatory blood pressure monitoring, cardiovascular assessment, laboratory testing, and validated questionnaires assessing perceived stress and insomnia symptoms. Circadian disruption will be classified using a predefined five-component research index based on actigraphy measures. Participants with three or more abnormal circadian indicators will be classified as Circadian Disruption Index-positive and compared with participants with zero to two abnormal indicators. The primary outcome is mean 24-hour systolic blood pressure. Secondary outcomes include nocturnal blood pressure patterns, cardiac structure and function, heart-rate variability, stress, insomnia symptoms, and individual circadian measures. The Circadian Disruption Index is a study-specific research classification and is not intended to diagnose a circadian rhythm sleep-wake disorder.
Detailed description
This study is designed to investigate the relationship between circadian organization, sleep-wake patterns, and cardiovascular characteristics in young adults with established essential arterial hypertension. The study is based on the hypothesis that circadian disruption may be associated with an adverse cardiovascular phenotype, particularly alterations in the 24-hour blood pressure profile and early markers of cardiovascular remodeling. Circadian organization will be assessed using prolonged ambulatory wrist actigraphy. A predefined research index will integrate five complementary indicators of circadian rhythmicity and sleep-wake regularity. The index is intended to provide an operational and reproducible classification of the degree of circadian disruption within the study population rather than to establish a clinical diagnosis of a circadian rhythm sleep-wake disorder. Cardiovascular assessment will include ambulatory blood pressure monitoring, echocardiographic assessment of cardiac structure and function, heart-rate variability, and selected metabolic and inflammatory biomarkers. Psychological and sleep-related factors will also be assessed in order to explore the potential contribution of perceived stress and insomnia symptoms to the relationship between circadian organization and cardiovascular characteristics. The primary analytical approach will compare participants classified as having a positive Circadian Disruption Index with those classified as negative. Multivariable statistical models will subsequently be used to determine whether the observed association between circadian disruption and cardiovascular parameters persists after adjustment for relevant demographic, anthropometric, hypertension-related, treatment-related, and sleep-related factors. An additional exploratory objective is to evaluate whether a combination of cardiovascular, metabolic, behavioral, and psychological characteristics can identify participants with a higher probability of circadian disruption. This exploratory analysis may contribute to the development of a preliminary cardiovascular-circadian risk metric that could subsequently be evaluated and validated in independent cohorts. The study is observational and does not assign participants to a therapeutic intervention. The research classification of circadian disruption should not be interpreted as a diagnosis of a circadian rhythm sleep-wake disorder, and the findings will be interpreted in the context of the overall clinical characteristics of the participants.
Interventions
None listed
Sponsors
Medical University of Sofia
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to 45 Years
Healthy volunteers
No
Inclusion criteria
1. Adults aged 18 to 45 years. 2. Established diagnosis of essential arterial hypertension. 3. Stable antihypertensive treatment for at least 4 weeks before enrollment, when pharmacological treatment is prescribed. 4. Ability and willingness to undergo 14 consecutive days of wrist actigraphy using the CamNtech MotionWatch 8. 5. Ability and willingness to undergo 24-hour ambulatory blood pressure monitoring. 6. Ability to provide written informed consent.
Exclusion criteria
1. Shift work or night-duty work. 2. Known secondary hypertension. 3. Previously diagnosed circadian rhythm sleep-wake disorder. 4. Known obstructive sleep apnea or other clinically significant sleep-related breathing disorder. 5. Known clinically significant cardiovascular disease other than uncomplicated essential arterial hypertension. 6. Diabetes mellitus. 7. Chronic kidney disease with clinically significant renal impairment. 8. Active thyroid disease or other clinically significant endocrine disorder that may affect blood pressure or circadian rhythm. 9. Current treatment with medications known to substantially alter sleep-wake rhythm or circadian timing. 10. Regular use of hypnotic or sedative medication that could substantially affect actigraphic sleep assessment. 11. Pregnancy. 12. Inability to comply with study procedures or insufficient actigraphy/ABPM recording quality. 13. Any acute illness or unstable medical condition that, in the investigator's opinion, could substantially influence the study outcomes.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Mean 24-Hour Systolic Blood Pressure | During the 14-day actigraphy period | Mean systolic blood pressure over a valid 24-hour ambulatory blood pressure monitoring period performed during the 14-day actigraphy recording period. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Mean 24-Hour Diastolic Blood Pressure | During the 14-day actigraphy period | Mean diastolic blood pressure over a valid 24-hour ambulatory blood pressure monitoring period. |
| Mean Nocturnal Systolic Blood Pressure | During the 14-day actigraphy period | Mean systolic blood pressure during the predefined nocturnal period measured by 24-hour ambulatory blood pressure monitoring. |
| Mean Nocturnal Diastolic Blood Pressure | During the 14-day actigraphy period | Mean diastolic blood pressure during the predefined nocturnal period measured by 24-hour ambulatory blood pressure monitoring. |
| Nocturnal Systolic Blood Pressure Dipping | During the 14-day actigraphy period | Percentage reduction in mean nocturnal systolic blood pressure compared with mean daytime systolic blood pressure. |
| Non-Dipping and Reverse-Dipping Blood Pressure Pattern | During the 14-day actigraphy period | Proportion of participants demonstrating a non-dipping or reverse-dipping nocturnal systolic blood pressure pattern based on 24-hour ambulatory blood pressure monitoring. |
| Left Ventricular Mass Index | At baseline assessment | Left ventricular mass indexed to body surface area, assessed by transthoracic echocardiography. |
| Left Atrial Volume Index | At baseline assessment | Left atrial volume indexed to body surface area, assessed by transthoracic echocardiography. |
| E/e' Ratio | At baseline assessment | Ratio of early transmitral flow velocity to early diastolic mitral annular velocity as an echocardiographic measure of left ventricular diastolic function. |
| Global Longitudinal Strain | At baseline assessment | Left ventricular global longitudinal strain assessed by transthoracic echocardiography. |
| Heart Rate Variability | During the 14-day actigraphy period | Heart rate variability assessed using standard time-domain parameters, including SDNN and RMSSD. |
| Perceived Stress | At baseline assessment | Perceived psychological stress was assessed using the 10-item Perceived Stress Scale (PSS-10). Each item is rated on a 5-point scale from 0 (never) to 4 (very often), yielding a total score of 0-40. Higher scores indicate greater perceived stress. |
| Insomnia Severity | At baseline assessment | Severity of insomnia symptoms was assessed using the Insomnia Severity Index (ISI), a 7-item questionnaire assessing difficulties with sleep onset, sleep maintenance, early morning awakening, satisfaction with sleep, interference with daily functioning, noticeability of sleep problems, and distress caused by sleep difficulties. Each item is scored from 0 to 4, yielding a total score of 0-28, with higher scores indicating greater insomnia severity. Scores of 0-7 indicate no clinically significant insomnia, 8-14 subthreshold insomnia, 15-21 moderate clinical insomnia, and 22-28 severe clinical insomnia. |
| Interdaily Stability | During the 14-day actigraphy period | Interdaily Stability (IS) derived from actigraphy to quantify the consistency of the 24-hour activity-rest pattern across monitoring days. |
| Intradaily Variability | During the 14-day actigraphy period | Intradaily Variability (IV) derived from actigraphy to quantify fragmentation of the activity-rest rhythm within individual days. |
| Relative Amplitude | During the 14-day actigraphy period | Relative Amplitude (RA) derived from actigraphy as a measure of the contrast between the most active and least active periods of the 24-hour cycle. |
| Wake-Time Variability | During the 14-day actigraphy period | Variability in wake time across the 14-day actigraphy monitoring period, expressed as the standard deviation of wake time. |
| Sleep-Onset Time Variability | During the 14-day actigraphy period | Variability in sleep-onset time across the 14-day actigraphy monitoring period, expressed as the standard deviation of sleep-onset time. |
Countries
Bulgaria
Outcome results
None listed