No registrations found.
ID
Source
Brief title
Health condition
(non-atopic) asthma
Vitamin D
(niet-atopisch) astma
vitamine D
Sponsors and support
Intervention
Outcome measures
Primary outcome
1. The difference between vitamin D levels of patients with non-atopic asthma and of patients with atopic asthma;
2. The difference between vitamin D levels of patients with non-atopic asthma and of non-atopic healthy subjects.
Secondary outcome
Not applicable at this time.
If a difference is found between non-atopic asthmatics and controls, virus serology will be determined and compared between these groups and genetic tests can be performed and compared between these groups.
Background summary
Rationale:
Vitamin D levels have been linked to asthma and respiratory tract infections. The mechanism of this association is not yet totally understood, but vitamin D seems to have an immune modulatory effect and play a role in host defence against infections. The role of vitamin D in asthma, could especially be important in non-atopic patients, since non-atopic asthma often starts after a respiratory tract infection. Data on vitamin D levels in non-atopic asthma are lacking. By comparing vitamin D levels in non-atopic asthma patients to those in atopic asthmatics and in healthy non-atopic controls, the role of vitamin D might be better understood.
Objective:
To compare the levels of vitamin D in subjects with non-atopic asthma to those in subjects with atopic asthma and those in healthy non-atopic subjects.
Study design:
Case-control study.
Study population:
Adult patients with non-atopic asthma will be recruited from a large cohort of non-atopic asthma patients, composed in a previous study (PANAMA 1-3).
Two other groups will be composed: One group of atopic asthma patients and one group of healthy non-atopic controls. These two groups will be matched to the non-atopic asthma group for age, sex and BMI.
Main study parameters/endpoints:
The difference between vitamin D levels of patients with non-atopic asthma and patients with atopic asthma and the difference between vitamin D levels of patients with non-atopic asthma and healthy non-atopic subjects.
Study objective
We hypothesize that vitamin D levels in non-atopic asthma are lower than those in atopic asthmatics and healthy non-atopic controls.
Study design
When patients are included, one visit is planned. No further appointments are made.
Intervention
N/A
J.C. Groot, de
Leeuwarden 8934 AD
The Netherlands
+31 (0)58 2863874
christa.de.groot@znb.nl
J.C. Groot, de
Leeuwarden 8934 AD
The Netherlands
+31 (0)58 2863874
christa.de.groot@znb.nl
Inclusion criteria
Group 1:
1. Outpatients with non-atopic asthma, determined by negative alatop;
2. Age ≥ 18 yrs;
3. Pulmonologists diagnosis of asthma;
4. Documented reversibility in FEV1 of > 12% predicted OR airway hyperresponsiveness to inhaled methacholine.
Group 2:
1. Outpatients with atopic asthma, determined by known positive alatop or skin prick test;
2. Age ≥ 18 yrs;
3. Pulmonologists diagnosis of asthma;
4. Documented reversibility in FEV1 of > 12% predicted OR airway hyperresponsiveness to inhaled methacholine.
Group 3:
1. Subjects without pulmonary history or pulmonary complaints;
2. Age ≥ 18 yrs;
3. No signs of allergy and negative alatop;
4. Normal spirometry.
Exclusion criteria
Group 1:
1. Patients with smoking history of > 10 packyears and persistent airflow obstruction (post bronchodilator FEV1 < 80%pred): excluded if reversibility in FEV1 < 12% predicted OR TLCO < 80%pred;
2. Pregnancy;
3. Use of supplements containing vitamin D analogues in the last 6 months;
4. Other pulmonary diseases.
Group 2:
1. Patients with smoking history of > 10 packyears and persistent airflow obstruction (post bronchodilator FEV1 < 80%pred): excluded if reversibility in FEV1 < 12% predicted OR TLCO < 80%pred;
2. Pregnancy;
3. Use of supplements containing vitamin D analogues in the last 6 months;
4. Other pulmonary diseases.
Group 3:
1. Pulmonary history or current pulmonary complaints;
2. Use of supplements containing vitamin D analogues in the last 6 months;
3. Pregnancy.
Design
Recruitment
Followed up by the following (possibly more current) registration
Other (possibly less up-to-date) registrations in this register
No registrations found.
In other registers
| Register | ID |
|---|---|
| NTR-new | NL2502 |
| NTR-old | NTR2620 |
| CCMO | NL33519.099.10 |
| ISRCTN | ISRCTN wordt niet meer aangevraagd. |
| OMON | NL-OMON34269 |