Abstract
Purpose: :
The aim of this matched-pair analysis was to identify risk factors associated with retinopathy of prematurity (ROP) requiring laser treatment in a cohort of very immature preterms.
Methods: :
We evaluated a cohort of 767 preterms born from 2001 to 2009, 54 of which required laser treatment. From the untreated cohort, we tried to assign matched controls to the treated infants. Matching criteria were set to: 1.) identical gender, 2.) identical (non)-multiple status, 3.) equal gestational age (GA), deviation ≤ 5%, and equal birthweight (BW), deviation ≤10%.
Results: :
We were able to generate 46 matched pairs (MP). Twenty-one MPs (46%) were male, eleven (24%) were multiples. GA was 24.7±1.81 weeks for treated preterms and 24.7±1.84 for controls. BW was 661±261g for treated preterms and 665±267g for controls. The incidence of systemic inflammatory response syndrome (SIRS) was higher for treated preterms compared to controls (70% vs. 46%; p=0.0188), the clinical risk index for babies-score was higher for treated subjects (9.7±3.5 vs. 8.1±2.8; p=0.0161), as was severity of intraventricular hemorrhage (1.0±1.2 vs. 0.5±0.9; p=0.0448). As well, maximum oxygen concentration for ventilation was higher for treated infants (0.71±0.29 vs. 0.57±0.22, p=0.0097). The proportion of time using laryngal tube ventilation compared to continuous positive airway pressure (CPAP) ventilation was longer in preterms requiring laser treatment (37.5±33.7% vs. 19.2±21.9%; p=0.0104), while total time of respiratory ventilation was similar in treated and control groups (40.0±25.4d vs. 44.4±21.3d; p=0.2911).
Conclusions: :
In this study we were able to identify distinct risk factors for development of treatment-requiring ROP even for very immature preterms. For clinical practice, restrictive use of oxygen and an effort to utilize CPAP ventilation, whenever possible may have protective effects regarding incidence of treatment-requiring ROP.
Keywords: retinopathy of prematurity • clinical (human) or epidemiologic studies: risk factor assessment • laser