Caffeine intake is inversely associated with polycystic ovary syndrome. A case-control study

Introduction: Polycystic ovary syndrome (PCOS) is a highly prevalent reproductive condition (5-20%) that involves many associated endocrine and metabolic disorders such as hyperinsulinemia. Some studies suggest that caffeine intake has a protective role against PCOS. In addition, individuals' lifestyles such as smoking, or alcohol consumption may also influence development of PCOS. Objectives: In this case-control study, we explored associations between caffeine, alcohol and tobacco consumption and PCOS Methods: The study enrolled 126 women diagnosed with PCOS and 159 healthy women living in Murcia (Spain) from September 2014 to May 2016. The diagnostic of PCOS was established following the Rotterdam criteria (hyperandrogenism, oligoanovulation and polycystic ovaries morphology). For data collection, we used a validated food frequency questionnaire to determinate alcohol and caffeine intake. We applied a tobacco and alcohol consumption questionnaire to evaluate these habits. We estimated adjusted odds ratios and 95% confidence intervals using multivariable logistic regression. Results: In the multivariable analysis, caffeine intake was inversely associated with PCOS (ORQ4 vs. Q1 = 0.29; 95% CI: (0.13; 0.64); P for trend = 0.01). We did not find any statistically significant association between alcohol and tobacco habits and total, anovulatory or ovulatory PCOS. Conclusions: We found coffee consumption may be a protective factor for PCOS. Few studies have explored the impact of this association. These results are consistent with a previous study. This relationship may due to caffeine increasing sex hormonebinding globulin hormones levels, which are found at lower concentrations in women with PCOS.