IGF-1: a potential biomarker for efficacy of sleep improvement with automatic airway pressure therapy for obstructive sleep apnea?

The positive impact of smoking on poor sleep quality is moderated by IGF1 levels in cerebrospinal fluid: a case-control study among Chinese adults

Objective

Previous research indicates associations between cigarette smoking, insulin-like growth factor-1 (IGF1), and sleep disturbances. This study aimed to examine the association between smoking and sleep quality and investigate the moderating role of IGF1.

Methods

This case-control study involved 146 Chinese adult males (53 active smokers and 93 non-smokers) from September 2014 to January 2016. Sleep quality and disturbances were evaluated using the Pittsburgh Sleep Quality Index (PSQI), which includes seven scales. Pearson correlation analysis and logistic regression analysis were utilized to examine the link between IGF1 levels in cerebrospinal fluid (CSF) and PSQI scores. The effect of IGF1 was assessed using the moderation effect and simple slope analysis, with adjustments made for potential confounders.

Results

Active smokers exhibited significantly higher global PSQI scores and lower IGF1 levels in CSF compared to non-smokers. A significant negative correlation was observed between IGF1 and PSQI scores (â = -0.28, P < 0.001), with a stronger association in non-smokers (Pearson r = -0.30) compared to smokers (Pearson r = -0.01). Smoking was associated with higher global PSQI scores (â = 0.282, P < 0.001), and this association was moderated by IGF1 levels in CSF (â = 0.145, P < 0.05), with a stronger effect at high IGF1 levels (Bsimple = 0.402, p < 0.001) compared to low IGF1 levels (Bsimple = 0.112, p = 0.268). Four subgroup analysis revealed similar results for sleep disturbances (Bsimple = 0.628, P < 0.001), with a marginal moderation effect observed on subjective sleep quality (Bsimple = 0.150, P = 0.070). However, independent associations rather than moderating effects were observed between IGF1 and sleep efficiency and daytime disturbance.

Conclusion

We provided evidence to demonstrate the moderation effect of IGF1 on the relationship between smoking and sleep in CSF among Chinese adult males.

Effects of gabapentin on slow-wave sleep period in critically ill adult patients: A randomized controlled trial

Sleep deprivation is a prevalent problem in critically ill patients, which leads to delayed recovery and delirium. Slow-wave sleep (SWS) is essential to energy restoration, tissue repair, and immune system strengthening. This study aimed to investigate the effects of gabapentin on SWS in critically ill patients. We performed a prospective open-label randomized controlled study to compare SWS and the clinical outcomes of gabapentin versus a control intervention in critically ill adult patients admitted to the intensive care unit (ICU) within 24 h. The patients' characteristics and sleep-related outcomes were recorded. The sleep-related outcomes, namely, bispectral analysis (BIS), the Richards-Campbell Sleep Questionnaire (RCSQ), and insulin-like growth factor-1 (IGF-1) levels, were evaluated. Furthermore, clinical outcomes and safety were assessed. Sixty patients from 348 cases were eligible for randomization. On day 3 of the study, patients in the gabapentin group had significantly increased SWS (66.79 vs. 0.00 min; p < 0.001), total sleep time (TST) (331.39 vs. 46.16 min; p = 0.001), RCSQ score (55.05 ± 20.18 vs. 32.80 ± 15.31; p < 0.001), and IGF-1 concentrations (84.33 ± 12.40 vs. 44.00 ± 10.20 ng/mL, p < 0.001) compared with the control group. Improvements in clinical outcomes, such as delirium, ICU-free days, and mechanical ventilator-free days, were observed; however, these differences did not reach statistically significant. Gabapentin at bedtime increased SWS, TST, and IGF-1 concentrations in critically ill patients. This regimen might be beneficial to critically ill patients for improving their sleep quality.

Symptoms During CPAP Therapy Are the Major Reason for Contacting the Sleep Unit Between Two Routine Contacts

STUDY OBJECTIVES

The demand for continuous positive airway pressure (CPAP) therapy outpaces available resources in most health care settings. We sought to evaluate predictors of nonroutine CPAP follow-up visits to improve resource utilization.

METHODS

We randomly analyzed 1,141 of the 2,446 patients who had received at least 1 year of CPAP therapy. Reasons for contacts, type (routine = R, nonroutine = NR), and mode (face-to-face or not, physician, nurse) were collected.

RESULTS

A total of 771 patients were classified R, and 370 NR. Age, profession, and sex did not affect the NR frequency. Symptoms increased the odds ratio for NR 12.1-fold, somnolence 34.8-fold, and suffocation at night 10.4-fold. Patients with nonroutine reasons abandoned CPAP therapy significantly (7.6-fold) more frequently than patients with routine reasons.

CONCLUSIONS

Symptoms during CPAP therapy predicted the nonroutine contacts well. In line with this, patients with symptoms have become a priority follow-up group, and could constitute the only follow-up policy when dealing with insufficient medical resources.