A Trial of Daily Ultraviolet Therapy to Reduce Cardiovascular Risk Factors

The investigators have shown that a single dose of ultraviolet irradiation (as found in sunlight) will lower blood pressure for around one hour. They are now testing whether daily UVA for two weeks will produce a sustained fall in BP in patients with high blood pressure.

They will also measure the effect of daily UVA on other cardiovascular risk factors.

Study Overview

• Status: Terminated
• Conditions: Hypertension
• Intervention / Treatment: Device: Ultraviolet A radiation; Device: Sham irradiation

Detailed Description

Epidemiological studies suggest that sunlight reduces all cause mortality, and particularly cardiovascular mortality.

The investigators have previously shown vasodilatation and a transient fall in blood pressure following irradiation of human volunteers with 2 standard erythemal doses of UVA radiation. This was independent of vitamin D and temperature rise and correlated with a nitric oxide synthase independent mobilisation of NO stores from the skin to the systemic circulation.

In this randomised, sham-controlled, cross-over double blind study, they will measure whether twice daily UVA administration can produce a sustained fall in BP and other cardiovascular risk factors in a cohort of pre-hypertensive patients.

• Study Type: Interventional
• Enrollment (Actual): 13
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Edinburgh, United Kingdom, EH4 2XU
    • Clinical Research Centre and Pharmacology Unit, Western General Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years and older (ADULT, OLDER_ADULT, CHILD)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Pre-hypertensives (BP 120-139/80-89).
• Fitzpatrick skin types 2 and above (i.e. the ability to tan)

Exclusion Criteria:

• History of skin cancer.
• Fitzpatrick type 1 skin (always burns, never tans).
• Red hair.
• Family history of melanoma in first degree relative.
• Atypical naevus syndrome.
• Planned holiday or foreign travel during and for 4 weeks before the period of the study.

• Concurrent administration of:

  • anti-hypertensive medication,
  • photosensitising medication,
  • systemic immunosuppressive medication.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: TREATMENT
• Allocation: RANDOMIZED
• Interventional Model: CROSSOVER
• Masking: DOUBLE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: Active; UVA irradiation.	Device: Ultraviolet A radiation; Twice daily with 10 Joules/cm2. Half body (one side) with Waldmann 100L phototherapy lamp fitted with UVA bulbs (main emission 320-410nm); Other Names: UVA
SHAM_COMPARATOR: Sham UVA irradiation	Device: Sham irradiation; As active, but lamps to be shielded with Amber 81 museum film which prevents transmission of <500nm, but permits visible light to pass.; Other Names: Screened UVA lamp

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
24 hour ambulatory blood pressure measurement	Before and after active and sham intervention period. Subjects will wear a 24 hour ambulatory blood pressure monitor for the 24 hour period before and after each 2 week intervention period. Change in 24 hour ambulatory blood pressure measurement will be the outcome measure.	Two weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Blood pressure	Measured with a mercury sphygmomanometer in clinical research facility. Change in blood pressure between the before and after measurements in the active and sham intervention.	Two weeks
Heart rate	Change in heart rate between the before and after measurements of the active and sham intervention. This will be measured manually in clinical research facility before and after active or sham intervention period.	Two weeks
Body Mass Index	Change in body mass index measured in clinical research facility before and after active and sham intervention period	Two weeks
Waist-Hip Ratio	Change in waist-hip ratio. Measured in clinical research facility before and after active or sham intervention period	Two weeks
Lipid profile	Change in lipid profile. Blood will be taken in the clinical research facility before and after active and sham intervention period. Analysis will be performed by the core specialist assay service at the adjacent Queens Medical Research Institute of the University of Edinburgh. Lipids are measured as a continuous variable.	Two weeks
Adipokine profile	Change in adipokine profile. Blood will be taken in the clinical research facility before and after active and sham intervention period. Analysis will be performed by the core specialist assay service at the adjacent Queens Medical Research Institute of the University of Edinburgh. Adipokines are measured as a continuous variable.	Two weeks
Glucose tolerance test	The standard National Health Service Lothian Glucose Tolerance Test protocol will be carried out and changes in outcome measures recorded. These will be the fasting glucose and the two hour glucose level. Both are continuous variables. Phlebotomy and glucose administration wil be performed in the clinical research facility before and after active and sham intervention period	Two weeks
HbA1c (glycosylated haemoglobin)	Change in glycosylated haemoglobin level. Blood will be taken in the clinical research facility before and after active and sham intervention period. Analysis will be performed by the core specialist assay service at the adjacent Queens Medical Research Institute of the University of Edinburgh. Glycosylated haemoglobin is measured as a continuous variable.	Two weeks
Fasting insulin level	Change in fasting insulin level. Fasting blood will be taken in the clinical research facility before and after active and sham intervention period. Analysis will be performed by the core specialist assay service at the adjacent Queens Medical Research Institute of the University of Edinburgh. Insulin levels are measured as a continuous variable.	Two weeks
Bio-impedance for body fat	Changes in body fat levels. These are measured in clinical research facility before and after active or sham intervention period. This is a continuous variable.	Two weeks
Serum Vitamin D level	Changes in serum Vitamin D level. This is a continuous variable. Blood will be taken in the clinical research facility before and after active or sham intervention period. Analysis will be performed by the core specialist assay service at the adjacent Queens Medical Research Institute of the University of Edinburgh.	Two weeks
Adaptive pigmentation	Changes in pigmentation. Measured in clinical research facility before and after active or sham intervention period. Colour will be measured on UV exposed back skin using a chromameter and the L*a*b*score. This is a continuous variable.	Two weeks
Mood	Changes in mood. Patients will complete a mood questionnaire in the clinical research facility at the appointment before and after the active or sham intervention period. This is a continuous variable.	Two weeks
Physical activity level- composite measure.	Differences in activity levels will be compared between active, sham and washout periods. A composite measure derived from the peak, mean, and overall activity will be recorded. Overall activity will be calculated as area under the curve over the measurement period. Activity will be measured as movement, recorded by continually worn actiwatches (movement monitors) throughout the duration of the study. These will be set to record movement in 1 minute epochs.	Two weeks

Collaborators and Investigators

• Sponsor: University of Edinburgh
• Investigators: Principal Investigator: Richard B Weller, MD FRCP, University of Edinburgh

Publications and helpful links

General Publications

• Liu D, Fernandez BO, Hamilton A, Lang NN, Gallagher JMC, Newby DE, Feelisch M, Weller RB. UVA irradiation of human skin vasodilates arterial vasculature and lowers blood pressure independently of nitric oxide synthase. J Invest Dermatol. 2014 Jul;134(7):1839-1846. doi: 10.1038/jid.2014.27. Epub 2014 Jan 20.

Study record dates

Study Major Dates

• Study Start (ACTUAL): May 2, 2017
• Primary Completion (ACTUAL): August 31, 2019
• Study Completion (ACTUAL): August 31, 2019

Study Registration Dates

• First Submitted: June 25, 2015
• First Submitted That Met QC Criteria: December 1, 2015
• First Posted (ESTIMATE): December 4, 2015

Study Record Updates

• Last Update Posted (ACTUAL): September 27, 2019
• Last Update Submitted That Met QC Criteria: September 25, 2019
• Last Verified: September 1, 2019

More Information

Terms related to this study

• Keywords: hypertension; ultraviolet
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Hypertension
• Other Study ID Numbers: PG/15/23/31362

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No