Screening for sleep-disordered breathing in people with type 1 diabetes by combining polysomnography with glucose variability assessment

AIMS

There are few published data on sleep-disordered breathing (SDB) in type 1 diabetes (T1DM). Here, we used a combination of polysomnography and glucose variability assessment to screen for SDB.

METHODS

In a prospective, single-centre study, adults with T1DM underwent polysomnography and continuous glucose monitoring during a single night. We measured high glucose variability and the occurrence of a low or very low glucose level. Mild and moderate-to-severe SDB were defined as an apnoea-hypopnoea index above 5/h and 15/h, respectively.

RESULTS

We studied 46 patients (25 men; median age: 42 [35-54]; diabetes duration: 18 years [13-29]; body mass index (BMI): 24.8 kg/m² [23.0-28.9]). SDB was present in 17 patients (37.0%) overall (mild SDB: n = 9; moderate-to-severe SDB; n = 8). When compared with the absence of SDB or mild SDB, moderate-to-severe SDB was associated with a higher BMI (29.8 kg/m² [27.8-31.1]) and a longer diabetes duration (26 years [18-31]) but not with above-target glucose variability or more sleep disorder symptoms. Conversely, sleep disorder symptoms were not more frequent in patients with above-target glucose variability.

CONCLUSION

SDB was highly prevalent and associated with obesity. According to the methods used here, sleep disorders were not associated with above-target glucose variability or low glucose values.

Correlation between the Epworth Sleepiness Scale and the Maintenance of Wakefulness Test in Obstructive Sleep Apnea Patients Treated with Positive Airway Pressure

BACKGROUND

The Epworth sleepiness scale (ESS) is often used to evaluate the impact of treatment in patients with obstructive sleep apnea hypopnea syndrome (OSA). We aimed to evaluate the correlation between ESS and the Maintenance of Wakefulness Test (MWT) in a population of OSA patients treated with positive airway pressure (PAP).

METHODS

We retrospectively included all patients during a 2-year period who were diagnosed with OSA in our sleep clinic and required PAP therapy. ESS was evaluated at baseline and after PAP therapy for all patients, and all had a concomitant MWT. Correlation between final ESS, change in ESS, and MWT were evaluated using Spearman's correlation. Given that MWT is considered as the gold standard, the diagnostic performance of ESS was evaluated against MWT.

RESULTS

Hundred thirty-four OSA patients were included. At the time of MWT, 89.6% of the patients were compliant (PAP use ≥4hours/night), and only 9 (6.7%) had persistent sleepiness despite PAP treatment (mean sleep latency at MWT<19.4min). Moderate correlation was observed between final ESS and MWT (Spearman's correlation coefficient=-0.42), but no correlation was found between change in ESS and MWT. Diagnostic performance was as follows for final ESS: sensitivity=55.6%, specificity=84.8%, PPV=20.8%, and NPV=96.4%.

CONCLUSIONS

ESS was moderately correlated with MWT in a population of OSA patients compliant with PAP therapy. In this population, ESS showed poor diagnostic performance in identifying patients with persistent excessive daytime sleepiness. CLINICALTRIALS.

GOV IDENTIFIER

NCT03629834.

Short-Term Assessment of Obstructive Sleep Apnea Syndrome Remission Rate after Sleeve Gastrectomy: a Cohort Study

BACKGROUND

Severe obesity is associated with a high prevalence of moderate-to-severe obstructive sleep apnea syndrome (OSA). Bariatric surgery has been shown to effectively reduce excess weight and comorbidities.

METHODS

We evaluated the remission rate of moderate-to-severe OSA (apnea-hypopnea index (AHI) ≥ 15) following sleeve gastrectomy. We performed a single-center retrospective chart review of all patients who underwent preoperative polysomnography (PSG) or polygraphy before primary sleeve gastrectomy. Patients with moderate-to-severe OSA treated by continuous positive airway pressure (CPAP) also underwent postoperative PSG. Bivariate analysis was performed to evaluate the criteria associated with remission of moderate-to-severe OSA.

RESULTS

From 2013 to 2018, 39 of 162 patients (24.1%) scheduled for sleeve gastrectomy (SG) presented moderate-to-severe OSA requiring CPAP. Postoperative PSG was performed in 36 patients a mean of 9.9 ± 6.1 months after SG. Mean BMI decreased from 47.4 ± 8.4 to 36.3 ± 7.1 kg/m² (p < 0.001), and all patients reported clinical improvement of OSA symptoms. A remission of moderate-to-severe OSA was observed in 72.2% of patients with a mean decrease of AHI from 45.8 events/h to 11.3 events/h (p < 0.001). Postoperative neck circumference was the only factor associated with OSA remission.

CONCLUSION

SG is associated with a rapid improvement of moderate-to-severe OSA partially as a result of a reduction of neck circumference. However, the absence of correlation with excess weight loss suggests that other weight-independent factors may also be involved.

The relationship between metformin therapy and sleep quantity and quality in patients with Type 2 diabetes referred for potential sleep disorders

AIMS

Given that sleep disorders are known to be related to insulin resistance, and metformin has favourable effects on insulin resistance and on ventilatory drive, we sought to determine whether metformin therapy was related to sleep variables in a group of patients with Type 2 diabetes.

METHODS

We performed a retrospective, observational study of our centre's database for patients referred for potential sleep disorders and then compared metformin-treated patients with those not treated with the drug. All study patients had undergone the same standard polysomnographic procedure. A multivariate analysis was performed to establish whether or not there was an independent relationship between metformin use and sleep variables (after adjusting for age, gender, BMI, neck circumference, cumulated risk factors and insulin use).

RESULTS

We studied 387 patients (mean ± sd age: 58.4 ± 10.8 years), of whom 314 had been treated with metformin. Total sleep time and sleep efficiency were higher in metformin-treated patients than in patients not treated with metformin [total sleep time: 6 h 39 min vs. 6 h 3 min, respectively (P = 0.002); sleep efficiency: 77.9 ± 12.3 vs. 71.5 ± 17.2%, respectively (P = 0.003)]. These differences persisted after adjustment for covariates and were observed even although metformin users had a higher BMI than did non-users (median 37.5 vs. 34.8 kg/m(2) ; P = 0.045).

CONCLUSION

We showed that metformin therapy is associated with a longer sleep duration and better sleep efficiency. Randomized clinical trials are needed to confirm metformin's favourable effect on sleep quality and quantity.