Retinopathy of prematurity Eye Diseases Retinopathy of prematurity
Conditions
Interventions
The preterm infants selected for the study, all of whom conform to the inclusion criteria and whose parents/ legal guardians have given their informed consent, come from eight Portuguese Care Units of
Sponsors
Institute of Environmental Health (ISAMB) of the Lisbon School of Medicine
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: Preterm infants and their mothers, with at least one of the following newborn characteristics: 1. Born before 32 weeks of gestational age 2. Born with a birth weight of less than 1500 g
Exclusion criteria
Exclusion criteria: 1. Infants: 1.1. The existence of major congenital malformations 1.2. Ophthalmological pathologies, congenital or acquired (during the first 12 weeks of life) not related to ROP with the exception of conjunctivitis, keratitis and congenital obstruction of the tear-nasal canal 2. Mothers: 2.1. Diabetes 2.2. Gestation resulting from artificial fertilization 2.3. Insufficient clinical data 3. Legal guardians: 3.1. Absence of informed consent It should be noted that when the mother is excluded, the infant can still form part of the study, provided informed consent is given.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| 1. ROP staging (variable) is measured using the International Classification of ROP (I.C.R.O.P.-1984, revised in 2005). For ethical reasons and because it is an observational study with very premature infants, there are no medical tests made just for the study. The measure of this outcome comes from the ROP screening record performed by the ophthalmologists of the participating hospitals in accordance with the usual practice in Portugal. The first timepoint to measure this variable depends on the gestational age at birth of the infant: for infants born before 27 weeks of gestational age, this variable is measured at 31 weeks of gestational age; for infants born after 27 weeks of gestational age, this variable is measured at 4 weeks of life. The following timepoints depend on the measurement result at the previous timepoint, as follows: 1. Stage 2 ROP in zone I and stage 3 ROP in zone II: between 5 and 7 days 2. Immature vascularization in zone I without ROP, stage 2 ROP in zone II and regressing ROP in zone 1: between 1 and 2 weeks 3. Stage 1 ROP in zone 2 and regressing ROP in zone II: 2 weeks 4. Immature vascularization in zone II without ROP, Stage 1 or 2 in zone III and regressing ROP in zone III: between 2 and 3 weeks The last timepoint to measure this variable (ROP staging) corresponds to the timepoint at which measurement result is complete retinal vascularization or complete remission of ROP. ROP staging will allow the sample to be subdivided into groups. Infants who do not develop ROP will constitute the control group; infants who develop ROP will be separated into groups, according to the maximum stage of ROP reached and the need for treatment or not. 2. The following genetic polymorphisms of candidate genes in retinopathy of prematurity will be studied: 2.1. Angiotensinogen (rs699) 2.2. Angiotensin Converting Enzyme (ACE) (rs 1799752; rs 4291; insertion/deletion polymorphisms) 2.3. Angiotensin II type 1 receptor (AGTR1) (rs 5186; rs 427832) 2.4. Endoth | — |
Secondary
| Measure | Time frame |
|---|---|
| Circulating biomarkers: 1. Erythropoietin; insulin-like growth factor 1; brain-derived neurotrophic factor; regulated on activation, normal t cell expressed and secreted (RANTES); selectin; bilirubin. These variables will be measured using a commercial ELISA kit specific to each biomarker. 2. High-sensitivity C-reactive protein (HS PCR). Determinations of this variable will be performed by immunoturbidimetry. 3. Erythrogram and respective indices; leukogram and respective indices; thrombocytogram and respective indices. These variables will be measured using an automated hematology analyzer. As this is an observational study, all circulating biomarkers will be determined using the surplus of EDTA plasma or serum after routine laboratory parameters have been carried out in the infants during the first 4 weeks of life. For each of the circulating biomarkers, there are four timepoints, which correspond to the measurements performed during the first, second, third, and fourth week of life, respectively | — |
Countries
Portugal
Outcome results
None listed