The prevalence of gestational diabetes mellitus: The accuracy of the NSW perinatal data collection based on a private hospital experience

Abstract

Past studies have shown that the prevalence of gestational diabetes mellitus (GDM) has been underestimated, and this can have major implications for healthcare planning. With the changes in diagnostic criteria for GDM, we wanted to assess the accuracy of the diagnosis in a private hospital setting. Using data from the hospital's obstetric database, medical records and a private pathology provider, we established the true prevalence of GDM and compared it with the NSW Perinatal Data Collection. The recorded prevalence of 6.8% was well below the real value of 15.0%.

Prevalence of gestational diabetes according to commonly used data sources: an observational study

“…Other studies evaluating the prevalence of GDM in routinely collected population health datasets have shown similar findings [34, 35, 38, 39]. Zheng, Morris and Moses [38] determined the prevalence of GDM in a private hospital according to the hospital’s records and laboratory results and compared this to the New South Wales Perinatal Data collection. Much like the findings in our study, there were discrepancies in GDM prevalence according to different data sources and both hospital records and the Perinatal Data collection underestimated the prevalence of GDM.…”

“…Much like the findings in our study, there were discrepancies in GDM prevalence according to different data sources and both hospital records and the Perinatal Data collection underestimated the prevalence of GDM. For women who were missing a diagnosis of GDM in the Perinatal Data collection, about half had a diagnosis of GDM documented in the medical records and half were not documented in the women’s medical notes [38]. Bell et al [34] compared information on maternal diabetes status extracted from medical records of a random sample of 1200 women giving birth in New South Wales, Australia and compared this to two New South Wales Department of Health routinely collected datasets.…”

The gestational diabetes tsunami: Can we survive it?

“…The authors refer to two other Australian studies which report similar under-reporting of the prevalence of GDM. 6 In the other Wollongong paper, Moses et al…”

“…Two papers from Wollongong provide recent data on the 'size of the problem'. 5,6 The paper by Zheng et al 6 illustrates the inadequacies of data collection, with consequent 'major implications for healthcare planning' and resource allocation. By cross-referencing the Midwives' Data Collection from a private hospital with results of pregnancy oral glucose tolerance tests (OGTTs) from the local pathology provider, they found a major discrepancy in the GDM prevalence of the Data Collection (6.9%) and real GDM prevalence (~15.0%).…”

“…9 A recurring theme highlighted in these papers is the workforce and economic implications of the increasing prevalence of GDM. 5,6,9 It is worth pointing out that a number of studies do suggest that the economic outcome of application of the new criteria is a beneficial one, particularly when possible lifelong benefits for mother and infant are considered. 8,10 One of the possible methods of 'lightening the load' that we have implemented in the Australian Capital Territory is to stratify or 'triage' women to levels of risk.…”