Factors impacting compliance with palivizumab prophylaxis

Abstract

To the Editors: Palivizumab prophylaxis has proved effective in the prevention of serious respiratory syncytial virus (RSV) illness in high risk preterm infants. 1–3 Palivizumab is a humanized IgG antibody with a half-life of 17 to 20 days; therefore for optimal prevention it is crucial that palivizumab injections be administered every 30 days to maintain protective serum concentrations of anti-RSV antibody throughout the RSV season. A palivizumab outpatient prophylaxis program was initiated in 2000 in our tertiary level neonatal intensive care unit at the Anna Meyer Children’s Hospital of Florence, Italy. During the subsequent three respiratory seasons (November through April of 2000 to 2001, 2001 to 2002, 2002 to 2003), 156 high risk infants were prophylaxed according to the inclusion criteria for prophylaxis recommended by the American Academy of Pediatrics 4 and the Italian Neonatology Society. 5 We have retrospectively identified factors impacting compliance with the prophylaxis program. Compliance was defined as the receiving of all recommended palivizumab doses and was determined by comparing the actual number of injections given with the projected number an infant would receive. For each child we reviewed medical records and recorded demographic data. Several families (n = 16) were foreign-born and did not speak Italian. The overall compliance rate with all recommended doses of palivizumab throughout the three respiratory seasons was 86%. No demographic or neonatal characteristics seemed to impact compliance except for younger age at the beginning of the prophylaxis. Families with younger children were more compliant than those with older children (P < 0.05). We speculate that the family’s perception of their child’s health gradually changes with their growth and that the larger children were perceived as being healthier and therefore not requiring prophylaxis. Further evaluation is needed. We found that the strongest predictor for poor compliance was being foreign-born and nonnative speakers (P < 0.01). The overall compliance rate in foreign parents was 56%. The factors resulting in poor compliance in non-native speakers may include cultural differences and biases, ignorance or misunderstanding of clinical instructions, misperception of RSV illness severity and inadequate time spent on educating and informing these families. 6 In our opinion the most important characteristic was the difference in language and, related to this, our difficulties to communicate effectively. The use during the first 2 years of nonmedical translators was of little help in improving compliance with palivizumab, and we speculate that lack of medical training can lead to inadequate education and clarification of RSV risk and the importance of prophylaxis. For the third RSV prophylaxis season a letter was also included that explained the risks of RSV infection and the benefits of palivizumab prophylaxis for nonnative families. The addition of letters for nonnative families and their physicians improved compliance from 80% to 88%. This suggests a positive effect of written information and reinforcement by family health care providers. In Italy 4.2% of the population are immigrants; this is 1.0% less than the average in other European countries. 7 These families, often poor and living in crowded conditions, may bring additional risk factors for severe RSV illness. In Italy medication and health care for children is funded by the Public Health System, and this fact did not pose a barrier to compliance in this study. Italian law allows parents to have free days from work to care for their children’s health. As a result poor compliance was not thought to be job-related. Because the effectiveness of palivizumab in preventing severe RSV illness is highly dependent on compliance with the monthly injection regimen during the RSV season, we suggest that more innovative and effective approaches should be developed to overcome the barriers of an effective and compliant prophylaxis regimen. Maria Serenella Pignotti, M.D. Giuseppe Indolfi, M.D. Gianpaolo Donzelli, M.D., Ph.D. Acknowledgments. Our grateful thanks to the following for their contribution in preparing this paper: J. R. Groothuis, Global Medical Director Immunoscience Development, Abbott Laboratories; R. Merolla, Medical Manager, Abbott Laboratories; and G. M. Barbarotto, Senior Associate, Medical Communications, Abbott Laboratories.