Carotid artery intima-media thickness in polycystic ovary syndrome: a systematic review and meta-analysis

Abstract
Polycystic ovary syndrome (PCOS) is a common reproductive endocrine disorder associated with cardiovascular disease (CVD) risk factors and metabolic disturbances. This systematic review and meta-analysis was conducted to determine whether carotid intima-media thickness (CIMT), a marker of subclinical atherosclerosis, is higher in women with PCOS compared with women without PCOS. Primary articles reporting the mean CIMT in women with PCOS and controls were identified using Ovid MEDLINE, EMBASE and PUBMED. We performed a random-effects meta-analysis and created forest plots of the mean difference in CIMT and conducted tests for heterogeneity and publication bias. Studies were grouped by quality, defined by reporting reproducibility of CIMT and averaging both common carotid arteries versus one side for CIMT. From the 36 eligible full-text studies, 8 studies were included in the systematic review and 19 studies were included in the meta-analysis (total n= 1123 women with PCOS, n= 923 controls). The summary mean difference in CIMT among women with PCOS compared with controls was 0.072 mm [95% confidence interval (CI) 0.040, 0.105, P < 0.0001] for highest quality studies, 0.084 mm (95% CI 0.042, 0.126, P = 0.0001) for good quality studies, 0.041 (95% CI −0.038, 0.120, P = 0.310) for fair-quality studies and 0.045 (95% CI −0.020, 0.111, P = 0.173) for lower quality studies. Larger studies with a well-defined PCOS population using rigorous methodology may be required to draw a more robust conclusion. However, these results suggest women with PCOS are at a greater risk of premature atherosclerosis, which emphasizes the importance of screening and monitoring CVD risk factors in women with PCOS.