Sleep duration and snoring associate with hypertension and glycaemic control in patients with diabetes.

AIMS: Few studies have analysed the effect of sleep duration and snoring on hypertension and glycaemic control in patients with diabetes. This study aims to investigate the relationship of sleep duration and snoring on prevalent hypertension and glycaemic control in people with diabetes. METHODS: In the baseline survey of the REACTION study, 56 032 patients with diabetes were categorized into four groups according to self-reported sleep duration: < 6, 6-7.9, 8-8.9 and ≥ 9 h. Snoring frequency was evaluated as 'usually', 'occasionally' or 'never'. Hypertension was assessed by systolic blood pressure, diastolic blood pressure, self-reported previous diagnosis and antihypertensive medications. 'Good' glycaemic control was defined as HbA1c < 53 mmol/mol (7.0%) and 'poor' glycaemic control as HbA1c ≥ 53 mmol/mol (7.0%). RESULTS: Controlling for potential confounders and intermediates, sleep ≥ 9 h relative to intermediate sleep (6-7.9 h) was significantly associated with prevalent hypertension (OR: 1.25, 95% CI: 1.18-1.32) and poor glycaemic control (OR: 1.11, 95% CI: 1.05-1.18), and a U-shaped association was found between sleep duration and prevalent hypertension (P for quadratic trend = 0.019). Usually snoring was positively associated with prevalent hypertension (OR: 1.30, 95% CI: 1.23-1.37), whereas the association between snoring and poor glycaemic control was only on the borderline of statistical significance. CONCLUSIONS: Compared with a sleep duration of 6-7.9 h, longer sleep duration was associated with a higher prevalence of hypertension and poor glycaemic control in people with diabetes. Moreover, the relationship between sleep duration and prevalent hypertension was U-shaped. These findings may propose important public health implications for diabetes management.

The proposed terminology 'A(1c)-derived average glucose' is inherently imprecise and should not be adopted.

The proposed use of a more precise standard for glycated (A(1c)) and non-glycated haemoglobin would lead to an A(1c) value, when expressed as a percentage, that is lower than that currently in use. One approach advocated to address the potential confusion that would ensue is to replace 'HbA(1c)' with a new term, 'A(1c)-derived average glucose.' We review evidence from several sources suggesting that A(1c) is, in fact, inherently imprecise as a measure of average glucose, so that the proposed terminology should not be adopted.

Use of insulin-sensitizing agents in patients with polycystic ovary syndrome.

OBJECTIVE: To review the subject of polycystic ovary syndrome and the therapeutic use of insulin-sensitizing agents in patients with this endocrinopathy. METHODS: We present background information on this disorder and summarize the pertinent published literature. RESULTS: Polycystic ovary syndrome affects approximately 7.5% of reproductive-age women in the United States. Although specific diagnostic criteria for this condition have not been established, the presence of three major factors-chronic anovulation, hyperandrogenemia, and clinical signs of hyperandrogenism-has been proposed as essential for consideration of the diagnosis. A high ratio of serum luteinizing hormone to follicle-stimulating hormone is found in 60 to 75% of women with this syndrome. Treatment with metformin may yield heterogeneous responses in differing populations with polycystic ovary syndrome, but most studies have shown evidence of restoration of ovulatory cycling. In addition, weight loss and decreases in free and total testosterone levels have been reported. Troglitazone therapy proved somewhat less efficacious than metformin for restoring menstrual cycles and similar to metformin in producing hormonal responses. Because troglitazone is no longer available for clinical use, studies will need to be extended to other thiazolidinediones. Patients treated with another insulin sensitizer, D-chiro-inositol, have demonstrated improved insulin sensitivity, ovulatory rates, and biochemical findings. CONCLUSION: Current evidence suggests that the use of insulin-sensitizing agents in patients with polycystic ovary syndrome not only improves their sensitivity to the effects of insulin on glucose and lipid metabolism but also ameliorates clinical and biochemical manifestations of hyperandrogenism and increases rates of ovulation. Multicenter studies with larger numbers of patients are needed.