Please select the eligibility criteria that correspond to the clinical trial below.
Title: Randomised, Multi-Centre, Double-Blind, Placebo-Controlled Trial of Vitamin D Supplementation in Patients With Chronic Obstructive Pulmonary Disease
Brief Summary: The study null hypothesis is that vitamin D supplementation will not influence time to upper respiratory tract infection or time to moderate/severe exacerbation of chronic obstructive pulmonary disease.


Options:
A: Inclusion Criteria:

* Diagnosis of sickle cell disease (HbSS, HbSC, HbS Beta-thalassemia)
* Age 3 to 20 years old

Exclusion Criteria:

* Patient (or parent or guardian) unwilling or unable to provide written informed consent (and assent, if applicable)
* Patient unable or unwilling to comply with requirements of the clinical trial
* Participation in other therapeutic clinical trial
* Current diagnosis of rickets
* History of hypercalcemia or diagnosis of any medical condition associated with hypercalcemia, including primary hyperparathyroidism, malignancy, sarcoidosis, tuberculosis, granulomatous disease, familial hypocalciuric hypercalcemia
* Current use of corticosteroids, excluding inhaled steroids
* Current use of anticonvulsants (phenytoin, phenobarbital, carbamazepine)
* Therapy with thiazide diuretics or lithium carbonate
* Known liver or renal disease
* Patients taking medications for pulmonary complications of sickle cell disease not on a stable dose of medications, as defined by a change in medications or doses within the three months prior to study entry
* Patients on chronic red blood cell transfusion therapy
* Absence of baseline record of respiratory events (respiratory infections, asthma exacerbations, episodes of acute chest syndrome) for the preceding year
* Pregnancy
B: Principal Inclusion Criteria:

* Medical record diagnosis of COPD, emphysema or bronchitis
* Post-bronchodilator FEV1 / FVC \< 70% or post-bronchodilator FEV1 / slow VC \< 70%
* Post-bronchodilator FEV1 \< 80% predicted
* Age ≥ 40 years on day of first dose of IMP
* Smoking history ≥ 15 pack-years
* If a woman of child-bearing potential, is sexually abstinent or has negative pregnancy test within 7 days of recruitment and agrees to use reliable form of contraception until she has completed the study
* Able to give written informed consent to participate

Exclusion Criteria:

* Current diagnosis of asthma
* Known clinically significant bronchiectasis
* Known sarcoidosis, hyperparathyroidism, nephrolithiasis, active tuberculosis, vitamin D intolerance, liver failure, renal failure, terminal illness, lymphoma or other malignancy not in remission for ≥ 3 years
* Taking benzothiadiazine derivative, cardiac glycoside, carbamazepine, phenobarbital, phenytoin or primidone
* Taking dietary supplement or topical preparation containing vitamin D up to 2 months before first dose of IMP
* Treatment with any investigational medical product or device up to 4 months before first dose of IMP
* Breastfeeding, pregnant or planning a pregnancy
* Baseline corrected serum calcium \> 2.65 mmol/L
* Baseline serum creatinine \> 125 micromol/L
C: Inclusion Criteria:

* Patients aged between 6 and 14 years old, of both sexes
* Diagnosis of mild / moderate persistent asthma (GINA step 2/3)
* Allergy mite (Dermatophagoides farinae and pteronyssinus + + + / + + + +)
* Levels of vitamin 25 (OH) D \<30 ng / ml
* Signature of the informed consent of one parent or a legal representative

Exclusion Criteria:

* Cardiovascular disease or systemic
* anatomical abnormalities
* Other respiratory diseases
* Taking probiotics and / or prebiotics in the previous 2 weeks
* Taking vitamin D or systemic corticosteroids within 4 weeks
* Participation in other clinical trials
D: Inclusion Criteria:

* age 1-5 years
* physician-diagnosed asthma as per the Global Initiative for Asthma (GINA) guidelines
* URTIs as the main asthma trigger (parental report)
* ≥4 URTIs in the past 12 months (parental report)
* ≥1 asthma exacerbation requiring rescue oral corticosteroids (OCS) in the past 6 months or ≥2 in the past 12 months

Exclusion Criteria:

* intake or intention to use more than 400 IU/day of vitamin D supplement
* extreme prematurity (\<28 weeks gestation)
* infants \<12 months of age
* no vitamin D supplementation when breast-fed
* recent (\<1 year) immigrants from a region at high risk of rickets
* children with vitamin D restrictive diets e.g. vegans
* other chronic respiratory disease (broncho-pulmonary dysplasia; cystic fibrosis)
* condition(s) that alter calcium or vitamin D metabolism/absorption (hypo/hyperparathyroidism, kidney/liver disease, inflammatory bowel disease)
* medications that interfere with vitamin D metabolism (anti-epileptics, diuretics, antacids, anti-fungal drug)
* vitamin D supplementation \>1000 IU/ day in last 3 months
* anticipated difficult follow-up (unable to attend clinic visits; plan to leave the province).

Answer: B