We read with interest the recent paper by Shivakumar, et al. [1] comparing efficacy and safety of Caffeine and Aminophylline for apnea of prematurity. We noted few errors in the study. According to Table II, the apneic episodes are significant for the ‘1-3 days’ period (P=0.03), rather than for the ‘4-7 days’ period (P = 0.05). However, on page 281 of their article, the authors stated that "apneic episodes during 4-7 days of therapy was found to be significantly higher in Caffeine group (P=0.03)." Another piece of data that was likely erroneously mentioned was in figure 1 (study flow). In the caffeine group, the neonates who completed treatment and follow-up are mentioned as 79; however, it should have been 77. Similarly, in the aminophylline group, this number should be 79 rather than 77.

With regard to study methodology, we have few comments. Apnea of prematurity includes both central and obstructive apnea [2]. It would have been better if the study group was sub-classified into these two subgroups as those with predominant obstructive component are unlikely to respond to methylxanthines [2,3]. It might even have been better to exclude the babies with obstructive apnea. As per the results, some of the babies in the caffeine group had　upto　20 apneas in a day during the 4-7 days period after initiating methylxanthines as per the study protocol. It may be risky predisposing these preterms to significant hypoxia by not choosing/opting to go for higher mode of acceptable therapy like CPAP or conventional ventilation for recurrent apnea [2-4].

2. Zhao J, Gonzalez F, Mu D. Apnea of prematurity: from cause to treatment. Eur J Pediatr. 2011;170:1097-105.

3. Eichenwald EC. Committee on fetus and newborn. Apnea of prematurity. Pediatrics. 2016;137:1-7.

4. Kuzemko JA, Paala J.　Apnoeic attacks in the newborn treated with aminophylline. Arch Dis Child.　1973;48:404-6.