Prevalence of gestational diabetes mellitus in Europe: A meta-analysis.

TL;DR: This meta-analysis of primary research data reporting the prevalence of gestational diabetes mellitus in the general pregnant population of developed countries in Europe shows prevalence of GDM that is at the upper end of previous estimates in Europe.

About: This article is published in Diabetes Research and Clinical Practice.The article was published on 2017-07-01 and is currently open access. It has received 175 citations till now. The article focuses on the topics: Gestational diabetes & Population.

Summary

1. INTRODUCTION

• By productive rule I intend a rule that is not lexically restricted and can be applied to new items.
• Thus, the t or s epenthesis in BE points towards an explanation in terms of phonological hypercorrection of the BE tendency for word-final consonant cluster simplification, which is itself due to the absence of word-final consonant clusters in Bena L1.
• Finally, that hypercorrection has played an important role in the emergence of a given pattern does not necessarily mean that a synchronic analysis of the pattern as hypercorrection is still adequate.

2. THE NATURE OF THE DATA

• The present description of BE is based primarily on my observations of spontaneous BE use made during my joint work on the description of Bena L1 together with Mark Van de Velde and complemented by a number of recordings where BE is used spontaneously but was not the primary object of the recording.
• The remaining part of the fieldwork took place in SW Nigeria far from the Bena community with in total three different consultants, all males in their early 30s from the village of Dumne, all three having completed their secondary education and two of them also having spent some time at university.
• My colleague and I observed most speakers to produce occasional examples of pre-pausal t epenthesis.
• As I argue in section 5.3 there is a reasonable explanation for the problems I had with the elicitation, the existence of a sufficiently large and varied corpus of spontaneous BE speech would be needed to quantitatively substantiate my qualitative observations.
• As I have not collected the written pieces produced by the consultants consistently, I can give only rough estimates for the written corpus.

3. BENA ENGLISH (L2) CONSONANTS

• This section provides an overview of the consonant systems of BE as L2.
• As expected for an L2 system, there is much variation in how well the reference native pronunciation of L2 forms is approximated, both between speakers with different levels of proficiency and within speakers depending on various sociolinguistic parameters involved in a given speech situation.
• BE is characterised by pre-pausal devoicing, since only voiceless stops, fricatives and affricates occur word-finally before pause, resembling the Bena L1 pattern.

4. BENA (L1) CONSONANTS

• This section provides an overview of the consonant systems of Bena as L1 (cf. also Van de Velde & Idiatov 2017).
• Pre-pausal consonant lengthening in Bena is primarily of compensatory origin and related to the loss of final vowels in this position.
• An unconstrained phonological hypercorrection scenario has some trouble explaining the s epenthesis, since the deletion of a word-final post-coronal [s] is not so common in BE (see section 3).
• In the scenario for the emergence of pre-pausal t epenthesis after the coronal [s], [n] and [l], the transferred glottal closure is released too quickly, while the oral articulation of the preceding coronal is still largely sustained, which may occasionally result in a percept of an audibly released [t].

7. WORD-FINAL CONSONANT EPENTHESIS IN OTHER VARIETIES OF ENGLISH

• Besides BE, cases of word-final consonant epenthesis have been reported for a number of New Englishes as well as for several of the so-called Inner Circle Englishes.
• Finally, the role of glottalisation of word-final consonants in the emergence of the t and s epenthesis in SE and HE is different from what I argued for BE in section 6.
• Second, already for some time, both varieties have become involved in more intense contact with some more prestigious English varieties where the simplification of word-final consonant clusters is much less radical.

8. CONCLUSION

• I have presented a description of an interesting case of word-final consonant epenthesis from North-eastern NE of speakers whose L1 is the Adamawa language Bena (ISO 639-3: yun).
• It is clear that hypercorrection must have played an important role in the emergence of the epenthesis in all varieties.
• The analysis of the epenthesis in BE advanced in the paper has contributed to a better understanding of the details of word-final consonant epenthesis in other English varieties.
• The word-final consonant epenthesis pattern in the two Inner Circle Englishes, viz.
• Combined with the fact that pre-pausal glottalisation and lengthening prosody is relatively common cross-linguistically, the authors might expect such a sound pattern to arise occasionally in the languages of the world through regular sound change.

Figures

Table 3 Weighted multiple regression for GDM prevalence

Figure 1 – Flow diagram showing study selection

Table 2 Mean prevalence of GDM by several moderator variables

Table 1 – Characteristics of studies included in the review. [Large table included in separate file for publication as supplementary information online]

Frequently asked questions

Q1. What contributions have the authors mentioned in the paper "Prevalence of gestational diabetes mellitus in europe: a meta- analysis" ?

A systematic review and meta-analysis of observational primary research studies that have assessed the prevalence of Gestational Diabetes Mellitus ( GDM ) in the general population of pregnant women in developed countries in Europe, regardless of the specific diagnostic criteria used this paper. 

Q2. What are the future works in "Prevalence of gestational diabetes mellitus in europe: a meta- analysis" ?

Nevertheless, given the changing migration patterns across Europe, this prevalence estimate may well change in the future. The IADPSG guidelines suggest that all women or those at high risk have either fasting blood glucose, A1c or random blood glucose measured at the first prenatal visit and overt diabetes diagnosed if fasting blood glucose is 126mg/dl or higher or A1c 6. 5 % or higher [ 56 ]. Therefore, although estimates of GDM may be inflated by the potential inclusion of women with undiagnosed pre-existing diabetes, given the low prevalence of this it is unlikely that the effect on GDM estimates would be large. 

Q3. What is the strength of the present study?

A strength of the present study is that pooling studies using meta-analysis allows trends to be identified when there are inconsistencies between individual studies. 

Q4. What is the main reason for the increase in GDM prevalence?

With GDM being closely linked to type 2 diabetes mellitus and sharing some risk factors, the authors would expect to see an increase in GDM over time [1]. 

Q5. How long after a pregnancy is the incidence of type 2 diabetes mellitus?

Women are thought to be at the greatest risk of developing type 2 diabetes mellitus in the first five years following a pregnancy with GDM, with incidence of type 2 diabetes mellitus plateauing at around 10 years [6]. 

Q6. What was the definition of a study that was drawn from the general population of pregnant women?

Studies were defined as having a sample drawn from the general population of pregnant women if it was drawn from a source that covered the majority of the population, such as population registers, general practice registers or registers of clinics for pregnant women (in countries where registration at general practices and clinics for pregnancy women is near to universal). 

Q7. What were the limitations of the methodology?

The methodology had only minor limitations: only papers published in the English language were included, experts in the field were not contacted, grey literature was not identified and data extraction was only carried out by one author. 

Q8. What criteria were used to determine the prevalence of diabetes mellitus?

The prevalence estimate deriving from the criteria that were most commonly used in other papers in the review was the one selected for inclusion in the meta-analysis so that the estimate would be comparable to other studies in the review. 

Q9. What were the main factors that had a significant effect on the prevalence of GDM?

Sample age, diagnostic criteria, country the study was conducted in, year that data collection started and week of gestation at testing, all had a significant effect on the prevalence of GDM, whereas the quality category of studies, mean BMI, ethnicity, and family history of diabetes in samples, did not have a significant effect. 

Q10. What criteria were used to assess the quality of included studies?

The quality of included studies was assessed using a checklist based upon the example published by the Joanna Briggs Institute [12] which was designed for assessment of quality in systematic reviews of prevalence and incidence. 

Q11. Why was the prevalence estimate included in the meta-analysis?

Where individual studies reported multiple prevalence estimates according to different diagnostic criteria, only one prevalence estimate was included in the meta-analysis to avoid dependency effects.