Age at diagnosis of deaf babies: a retrospective analysis highlighting the advantage of newborn hearing screening

OBJECTIVE

Aim of the study was to assess the mean age at diagnosis of bilateral congenital hearing loss in the Audiology and Phoniatry Centre of the University of Turin, pointing out, by North-West Italy experience, the role of the newborn hearing screening in anticipating the age of diagnosis.

METHODS

This was a retrospective study. Forty-six congenital deaf babies were reviewed and age at diagnosis was assessed for each, taking in consideration the role of hearing loss risk factors. Eighteen babies (39%) were sent by the centres that participate to the newborn hearing screening program while 28 (61%) came for parental or pediatrician suspicion of hearing loss and for general language delay. Sixteen babies (35%) presented risk factors for hearing loss.

RESULTS

The mean age of identification of severe to profound hearing loss was 20.5 months (S.D.=15.3) in the whole group; considering the group of 28 babies not screened the mean age was 29.3 months (S.D.=13.4). This value decreased to 6.8 months (S.D.=3.6) in the group which underwent screening programme. This difference was statistically significant at Student's t-test (p<0.001). The average ages of diagnosis for healthy versus high risk children were significantly different only in the group of screened babies (p<0.05).

CONCLUSIONS

Childhood hearing impairment is one of the most common of congenital disorders, and even though there is a general trend of early identification, in reality age of diagnosis is as yet still too late even in developed countries. Our results show that newborn hearing screening could reduce the age at which infants with hearing loss are diagnosed and treated; this would improve speech, language, auditory outcome and the quality of parents and infant life.

[Technical ambulatory ECG innovations in performance evaluation]

Evaluating the performances of the instrumentation for Ambulatory ECG (AECG) analysis is a need largely recognized by both manufacturers and users. The most generally accepted method is the beat-by-beat comparison with annotated data bases, representing the different ECG abnormalities. Available data bases are aimed at arrhythmias detection evaluation, while it is recognized that the AECG ST-T changes detection has a great relevance in the analysis of ischemic heart disease. A concerted action of the European Community on Ambulatory Monitoring has been approved for achieving a comprehensive reference standard for assessing the quality of AECG instrumentation. The European project has been concentrated on the problem of ST-T analysis. An annotated data base is being developed with the contribution of european experts. A pilot study has been performed for establishing the criteria related to the development and annotation; particularly the definition of significant ST-T changes has been established. The data base will include 2-hour double channel AECG records, which contain at least one ST-T episode. Each record is annotated beat by beat according to the established scheme, identifying arrhythmic beats, rhythm changes, ST-T changes and noisy segments. A coordinating center has been established for interacting with the participating groups and for performing the operations related to the generation and management of the data base. For the time being 14 Groups of 8 Countries are participating to the annotation of the data base. A minimum number of 100 records is planned within June 1988.