ClinicalTrials.gg
RecruitingNCT05903950APCIQ-BPUpdated Oct 23, 2026

Air Pollution and Cardiovascular Disease in Qatar: an Interventional Study to Reduce Blood Pressure

An interventional study of Air cleaners with HEPA filter and Air cleaners without HEPA filter in Hypertension, Systolic, Metabolic Syndrome and Typ 2 Diabetes, sponsored by Weill Cornell Medical College in Qatar. Recruiting at 1 site in Qatar. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-10-23.

Sponsored by Weill Cornell Medical College in Qatar · Not applicable, Interventional, and Prevention

From the registry’s dates

  • Started Nov 2024; still recruiting 2 years later.
Updated Oct 23, 2026Eligibility revisedPrimary outcomes revised+1 moreGo to Updates ↓
Phase
Not applicable
Study type
Interventional
Enrollment
100
Allocation
Randomized
Ages
18 Years to 65 Years
Sex
All
01

Study summary

The main objective is to determine if in-home portable air cleaners provide persistent reductions in PM2.5 exposures and improvements in systolic blood pressure and biochemical parameters over one week in patients with metabolic syndrome or type 2 diabetes residing in Qatar.

Read the detailed description

Chronic cardio-metabolic diseases such as hypertension and diabetes contribute disproportionately to global morbidity and mortality and are increasing believed to have multiple environmental influences.

PM2.5 is the fifth leading risk factor for global mortality - largely due to cardiovascular disease (CVD). Reducing personal exposure to air pollution has shown promise in improving key cardiovascular risk factors (blood pressure and insulin resistance) in limited studies, but durability of these effects is not known. Personal air cleaners have been shown to decrease personal exposure to PM2.5 and reduce blood pressure in small studies and may serve as a pragmatic intervention in high-risk patients in whom air pollution is a strong contributor to cardiovascular health.

02

Conditions studied

  • Hypertension, Systolic
  • Metabolic Syndrome
  • Typ 2 Diabetes

Keywords

  • hypertension
  • metabolic syndrome
  • air pollution
  • Type 2 Diabetes
03

In context

Isolated Systolic Hypertension

35 studies on the registry are indexed under Isolated Systolic Hypertension; 8 are open to participants now.

This study's planned enrollment of 100 is close to the median of 100 across 31 interventional studies indexed under Isolated Systolic Hypertension.

Browse Isolated Systolic Hypertension studies →

Lead sponsor

Weill Cornell Medical College in Qatar is the lead sponsor of 13 studies on the registry; 5 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

The criteria were revised on the registry on Oct 23, 2026. See what changed

Ages eligible
18 Years to 65 Years
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Age ≥18 and less than 65 years old
  • Living in a single residence (home, apartment) located anywhere in Qatar
  • Mild systolic hypertension: screening visit systolic BP 130 to 159 mm Hg (off treatment or taking ≤ 2 BP medications that have been stable without changes during prior one week)
  • Either:

Type 2 diabetes patients ( > 6.5%) OR Non-type 2 diabetes patients with two or more additional criteria for the metabolic syndrome,

  • Waist circumference ≥102 cm if male and ≥88 cm if female
  • Fasting triglycerides ≥150 mg/dL (or taking a triglyceride-lowering medication)
  • HDL-C ≤ 40 mg/dL if male and ≤ 50 mg/dL if female (or taking an HDL-raising medication),
  • Fasting glucose ≥100 mg/dL (or taking an antidiabetic medication)

Exclusion criteria

Exclusion Criteria:

  • Pregnancy (self-reported)
  • ≥stage 4 kidney disease (estimated \<30 ml/min).
  • A medical condition placing the participant at risk from participation (per investigators)
  • Expected overnight travel outside their residence during the study
  • HEPA filter within the ACs of the residence (self-reported) or individual use of HEPA filter filter
  • Unable to comprehend/sign an
  • Lung disease requiring oxygen
  • Cancer receiving treatment.
  • Type 1 diabetes or MODY diabetes
  • Screening visit: BP ≥160/100 mm Hg
  • Medication changes in the past week. If participants are on medications for high BP or hyperlipidemia, they will need to have had stable therapy for at least one week with no planned changes during the study
  • Left upper arm circumference >17 inches as this will make BP levels inaccurate with the home monitor used
  • Acute illness or infectious symptoms within the prior 4 weeks.
Terms in these criteria, in plain language(3)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

HbA1c

A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.

GFR and eGFR (kidney filtering)

GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².

Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

05

Study design

Phase
Not applicable
Primary purpose
Prevention
Allocation
Randomized
Intervention model
Crossover assignment
Masking
Triple (Participant, Investigator, Outcomes assessor)
Enrollment
100 participants (estimated)

Study arms

  • Active comparator
    Active mode

    In home use of portable air cleaners with a High Efficiency Particulate Air (HEPA) filter for one week.

    Device: Air cleaners with HEPA filter

  • Sham comparator
    Sham mode

    In home use of portable air cleaners without a High Efficiency Particulate Air (HEPA) filter for one week.

    Device: Air cleaners without HEPA filter

Interventions

  • DeviceAir cleaners with HEPA filter

    PM 2.5 exposure reduction using in home portable air cleaners fitted with HEPA filters

  • DeviceAir cleaners without HEPA filter

    Simulation of PM 2.5 exposure reduction using in home portable air cleaners without HEPA filters.

06

What researchers measure

Primary outcomes

  1. Change in Systolic Blood Pressure

    Mean change from baseline in systolic blood pressure

    Time frame: week 1, week 3

Secondary outcomes

  1. Change in Fasting Glycemia

    Mean change from baseline in fasting glycemia

    Time frame: week 4, week 10

  2. Change in Insulin Resistance Index

    Mean change from baseline in Insulin Resistance Index

    Time frame: week 4, week 10

07

Study locations

1 of 1 sites recruiting
08

References and documents

Individual participant data

Plan to share: Yes — Individual participant data that underlie the results reported in the article, after de-identification (test, tables, figures, and appendices).

Supporting information: Study protocol, Statistical analysis plan, Analytic code

Time frame: Immediately after publication. No end date.

Access criteria: Anyone who wishes to access the data

No publications or documents are linked to this record.

09

Updates

1 registry update since Sep 25, 2026
Eligibility
Maximum age 60 Years→65 Years; 3 inclusion criteria edited, 2 added, 1 removed; 2 exclusion criteria edited, 3 added, 4 removed
What changed in the criteria
Inclusion criteria
  • RemovedNon-smokers (100% abstinence from use of any smoking or vaping product during the prior year)
  • EditedAge ≥18 and less than 6065 years old
  • EditedMild systolic hypertension: screening visit systolic BP 130 to 159 mm Hg (off treatment or taking ≤ 2 BP medications that have been stable without changes during prior 4 weeksone week) plus ≥ 2 more additional criteria for the metabolic syndrome:
  • AddedEither:
  • AddedType 2 diabetes patients (HbA1c > 6.5%) OR Non-type 2 diabetes patients with two or more additional criteria for the metabolic syndrome,
  • EditedFasting glucose ≥100 mg/dL (or taking an antidiabetic medication)
Exclusion criteria
  • RemovedScreening visit urine positive for cotinine (NicAlert >100 ng/mL)
  • RemovedLiving with an active smoker who smokes indoors (by self-report)
  • RemovedHigh risk conditions that prohibit allowing home BP to be >130/80 mm Hg during the10-week trial including any cardiovascular disease (coronary artery disease, prior stroke, heart failure, peripheral arterial disease, aneurysm) or ≥ stage 3 kidney disease (estimated glomerular filtration rate < 60 ml/min)
  • Added≥stage 4 kidney disease (estimated glomerular filtration rate <30 ml/min).
  • EditedHEPA filter within the air conditionersACs of the residence (self-reported) or individual use of HEPA filter filter
  • RemovedScreening visit: BP ≥160/100 mm Hg or fasting blood glucose ≥126 mg/dL and confirmed diabetes with follow-up HbA1c ≥6.5%. If glucose is elevated ≥126 mg/dL but HbA1c<6.5%, they could still participate.
  • AddedType 1 diabetes or MODY diabetes
  • AddedScreening visit: BP ≥160/100 mm Hg
  • EditedMedication changes in the past 4 weeksweek. If participants are on medications for high BP or hyperlipidemia, they will need to have had stable therapy during prior 10 weeksfor at least one week with no planned changes during the study
Oct 23, 2026
Primary outcomes
1 time frame changed
What changed in the outcomes
  • Time frameChange in Systolic Blood Pressureweek 4, week 10 → week 1, week 3
Oct 23, 2026
Sponsor
Collaborators removed: Case Western Reserve University
Oct 23, 2026
Show all 1 update
  1. Oct 23, 2026
    Eligibility Maximum age 60 Years→65 Years; 3 inclusion criteria edited, 2 added, 1 removed; 2 exclusion criteria edited, 3 added, 4 removed
    What changed in the criteria
    Inclusion criteria
    • RemovedNon-smokers (100% abstinence from use of any smoking or vaping product during the prior year)
    • EditedAge ≥18 and less than 6065 years old
    • EditedMild systolic hypertension: screening visit systolic BP 130 to 159 mm Hg (off treatment or taking ≤ 2 BP medications that have been stable without changes during prior 4 weeksone week) plus ≥ 2 more additional criteria for the metabolic syndrome:
    • AddedEither:
    • AddedType 2 diabetes patients (HbA1c > 6.5%) OR Non-type 2 diabetes patients with two or more additional criteria for the metabolic syndrome,
    • EditedFasting glucose ≥100 mg/dL (or taking an antidiabetic medication)
    Exclusion criteria
    • RemovedScreening visit urine positive for cotinine (NicAlert >100 ng/mL)
    • RemovedLiving with an active smoker who smokes indoors (by self-report)
    • RemovedHigh risk conditions that prohibit allowing home BP to be >130/80 mm Hg during the10-week trial including any cardiovascular disease (coronary artery disease, prior stroke, heart failure, peripheral arterial disease, aneurysm) or ≥ stage 3 kidney disease (estimated glomerular filtration rate < 60 ml/min)
    • Added≥stage 4 kidney disease (estimated glomerular filtration rate <30 ml/min).
    • EditedHEPA filter within the air conditionersACs of the residence (self-reported) or individual use of HEPA filter filter
    • RemovedScreening visit: BP ≥160/100 mm Hg or fasting blood glucose ≥126 mg/dL and confirmed diabetes with follow-up HbA1c ≥6.5%. If glucose is elevated ≥126 mg/dL but HbA1c<6.5%, they could still participate.
    • AddedType 1 diabetes or MODY diabetes
    • AddedScreening visit: BP ≥160/100 mm Hg
    • EditedMedication changes in the past 4 weeksweek. If participants are on medications for high BP or hyperlipidemia, they will need to have had stable therapy during prior 10 weeksfor at least one week with no planned changes during the study
    Primary outcomes 1 time frame changed
    What changed in the outcomes
    • Time frameChange in Systolic Blood Pressureweek 4, week 10 → week 1, week 3
    Sponsor Collaborators removed: Case Western Reserve University
    + 5 other changes: verification date, description, conditions, arm descriptions and index terms

From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗

10

Registry details

Key details

Study ID
NCT05903950
Lead sponsor
Weill Cornell Medical College in Qatar
Responsible party
Sponsor
First posted
Jun 15, 2023
Start date
Nov 3, 2024
Primary completion
Dec 2026 (estimated)
Completion
Dec 2026 (estimated)
Last update
Oct 23, 2026

Study contacts

Charbel Abi Khalil, MD
Contact
cha2022@qatar-med.cornell.edu
+974 4492 8484
Charbel Abi Khalil, MD
principal investigator · Weill Cornell Medical College in Qatar

Oversight

Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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