Obstructive sleep apnoea (OSA) is a common disorder that is associated with serious comorbidities with a negative impact on quality of life, life expectancy and health costs. As OSA is related to obesity and is associated with sleep disruption, increased inflammation and oxidative stress, it is not surprising that OSA has an impact on the secretion of multiple hormones and is implicated in the development of many endocrine conditions. On the other hand, many endocrine conditions that can affect obesity and/or upper airways anatomy and stability have been implicated in the development or worsening of OSA. This bidirectional relationship between OSA and the endocrine system has been increasingly recognised in experimental and epidemiological studies and there are an increasing number of studies examining the effects of OSA treatment on endocrine conditions and vice versa. In this review article, we will critically appraise and describe the impact of OSA on the endocrine system including obesity, dysglycaemia, the pituitary, the thyroid, the adrenals, the reproductive system and the bones. In each section, we will assess whether a bidirectional relationship exists, and we will describe the potential underlying mechanisms. We have focused more on recent studies and randomised controlled trials where available and attempted to provide the information within clinical context and relevance.
Aikaterini Lavrentaki, Asad Ali, Brendan G Cooper and Abd A Tahrani
Antiopi Ntouva, Konstantinos A Toulis, Deepikshana Keerthy, Nicola J Adderley, Wasim Hanif, Rasiah Thayakaran, Krishna Gokhale, G Neil Thomas, Kamlesh Khunti, Abd A Tahrani and Krishnarajah Nirantharakumar
Type 2 diabetes is associated with an increased risk of fracture. Any factor that incrementally increases this risk should be taken into account when individualising treatment. Hypoglycaemia is a common complication of antidiabetes medications and suggested as a risk factor for fractures; yet, its real-life clinical impact is unclear.
A population-based, retrospective open cohort study using routinely collected data between 1st of January 1995 and 1st of May 2016 in The Health Improvement Network (THIN) database.
Patients with type 2 diabetes mellitus with documented hypoglycaemic events were compared to randomly matched patients with type 2 diabetes mellitus without documented hypoglycaemic events matched to exposed patients on age, sex, duration of diabetes and BMI. The primary outcome was any incident fracture. Secondary outcome was incident fragility (osteoporotic) fracture.
A total of 41 163 patients with type 2 diabetes were included: 14 147 patients in the exposed cohort and 27 016 patients in the unexposed cohort. Patients with a documented hypoglycaemic event were significantly more likely to sustain any fracture compared to patients with no record of hypoglycaemic events: adjusted IRR = 1.20 (95% CI: 1.12–1.30; P < 0.0001). Patients who had a documented hypoglycaemic event were significantly more likely to suffer a fragility fracture compared to controls: adjusted IRR = 1.24 (95% CI: 1.13–1.37; P < 0.0001).
Hypoglycaemic events are a significant risk factor for fractures in patients with diabetes mellitus. This observation is clinically relevant when individualising targets for glycaemic control and selecting antidiabetic agents.
Kumarendran Balachandran, Dana Sumilo, Michael W O'Reilly, Konstantinos A. Toulis, Krishna Gokhale, Chandrika Wijeyaratne, Arri Coomarasamy, Wiebke Arlt, Abd Tahrani and Krishnarajah Nirantharakumar
Objective: Obesity is very common in patients with obstructive sleep apnoea (OSA) and polycystic ovary syndrome (PCOS). Longitudinal studies assessing OSA risk in PCOS and examining the role of obesity are lacking. Our objective was to assess the risk of OSA in women with vs. without PCOS and to examine the role of obesity in the observed findings.
Design: Population-based retrospective cohort study utilizing The Health Improvement Network (THIN), UK.
Methods: 76,978 women with PCOS and 143,077 age-, BMI- and location-matched women without PCOS between January 2000 and May 2017 were identified. Hazard Ratio (HR) for OSA among women with and without PCOS were calculated after controlling for confounding variables using multivariate Cox models.
Results: Median patient age was 30 (IQR: 25 – 35) years; median follow-up was 3.5 (IQR: 1.4 – 7.1) years. We found 298 OSA cases in PCOS women vs. 222 in controls, with incidence rates for OSA of 8.1 and 3.3 per 10,000 person years, respectively. Women with PCOS were at increased risk of developing OSA (Adjusted HR=2.26, 95% CI: 1.89 – 2.69, p<0.001), with similar HRs for normal weight, overweight and obese PCOS women.
Conclusions: Women with PCOS are at increased risk of developing OSA compared to control women irrespective of obesity. Considering the significant metabolic morbidity associated with OSA, clinicians should have a low threshold to test for OSA in women with PCOS. Whether OSA treatment has an impact on PCOS symptoms and outcomes needs to be examined.