Diagnostic accuracy of oral glucose tolerance tests, fasting plasma glucose and haemoglobin A1c for type 2 diabetes in women with polycystic ovary syndrome: A systematic review and meta-analysis

Yitayeh Belsti; Joanne Enticott; Rafiatu Azumah; Chau Thien Tay; Lisa Moran; Ronald C W Ma; Anju E Joham; Joop Laven; Helena Teede; Aya Mousa

doi:10.1016/j.dsx.2024.102970

Diagnostic accuracy of oral glucose tolerance tests, fasting plasma glucose and haemoglobin A1c for type 2 diabetes in women with polycystic ovary syndrome: A systematic review and meta-analysis

Diabetes Metab Syndr. 2024 Feb 28;18(3):102970. doi: 10.1016/j.dsx.2024.102970. Online ahead of print.

Authors

Affiliations

¹ Monash Centre for Health Research and Implementation (MCHRI), Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Australia.
² Robinson Research Institute, The University of Adelaide AHMS Building, North Terrace, Adelaide, South Australia, 5005, Australia.
³ Dept of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong, China; Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, China.
⁴ Monash Centre for Health Research and Implementation (MCHRI), Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Australia; Diabetes and Endocrine Units, Monash Health, Melbourne, Victoria, 3168, Australia.
⁵ Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynaecology, Erasmus University Medical Center, Rotterdam, Netherlands.
⁶ Monash Centre for Health Research and Implementation (MCHRI), Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Australia. Electronic address: aya.mousa@monash.edu.

PMID: 38442646
DOI: 10.1016/j.dsx.2024.102970

Abstract

Aims: To inform international guidelines, a systematic review and meta-analysis was conducted to assess the performance of diagnostic methods for type 2 diabetes in women with polycystic ovary syndrome (PCOS).

Methods: An updated systematic search was conducted on five databases from 2017 until October 2023 and combined with prior searches (from inception). Meta-analyses of diagnostic accuracy tests were conducted.

Results: Nine studies comprising 2628 women with PCOS were included. Against the oral glucose tolerance test, a haemoglobin A1C (HbA1c) ≥ 6.5% had a pooled sensitivity of 50.00% (95% confidence interval (CI): 35.53-64.47), specificity of 99.86% (95%CI: 99.49-99.98), and positive and negative predictive values of 92.59% (95%CI: 75.27-98.09) and 98.27% (95%CI: 97.73-98.68), respectively, with an accuracy of 98.17% (95%CI: 97.34-98.79). Fasting plasma glucose values ≥ 7.0 mmol/L had a pooled sensitivity of 58.14% (95%CI: 42.13-72.99), specificity of 92.59% (95%CI: 75.35-98.08), positive and negative predictive values of 92.59% (95%CI: 75.35-98.08) and 99.09% (95%CI: 98.71-99.36), respectively, and an accuracy of 99.00% (95%CI: 98.46-99.39) against the oral glucose tolerance test.

Conclusions: To our knowledge, this is the first systematic review assessing the performance of diagnostic methods for type 2 diabetes in women with PCOS. We demonstrate that using a cut-off for HbA1c of ≥6.5% in this population may result in misdiagnosis of half of the women with type 2 diabetes. Our results directly informed the recommendations of the 2023 International PCOS Guideline, suggesting that the oral glucose tolerance test is the optimal method for screening and diagnosing type 2 diabetes in women with PCOS and is superior to fasting plasma glucose and HbA1c.

Keywords: Diagnostic accuracy; Fasting glucose; Glycated haemoglobin A1c; Oral glucose tolerance test; Polycystic ovary syndrome; Screening; Sensitivity; Specificity; Type 2 diabetes.

Publication types

Review