Gender differences in the effect of comorbid insomnia symptom on depression, anxiety, fatigue, and daytime sleepiness in patients with obstructive sleep apnea

PURPOSE

This study investigated gender differences in the effect of comorbid insomnia symptom on depression, anxiety, fatigue, daytime sleepiness, and quality of life in patients with obstructive sleep apnea. There are gender differences in the presentation of obstructive sleep apnea. However, the influence of gender on the presentation of comorbid insomnia symptom and obstructive sleep apnea is not known.

METHODS

Allparticipantsperformed overnightpolysomnography and completed a battery of questionnaires including Beck Depression Inventory, State-Trait Anxiety Inventory, Multidimensional Fatigue Inventory, Epworth Sleepiness Scale, and Short Form-36 Health Survey. Insomnia symptom was defined as present if a patient had any insomnia complaints longer than 1 month and at least one time per week.

RESULTS

Six hundred fifty-five adult patients with obstructive sleep apnea were enrolled; 233 (35.5 %) reported comorbid insomnia symptom with obstructive sleep apnea. The severity of obstructive sleep apnea was not related to comorbid insomnia symptom. Based on linear regression, women had higher depression, fatigue, and daytime sleepiness and lower health-related quality of life than men (all, p<0.05). The presence of insomnia symptom had negative effects on fatigue (p=0.005) and quality of life only (p=0.015) in men but not in women when taking gender-by-insomnia interaction into consideration. There were significant differences in polysomnography-based sleep architecture between the obstructive sleep apnea-only and obstructive sleep apnea-insomnia groups, but only in the subgroup of men.

CONCLUSIONS

Men are more prone to the negative impact of comorbid insomnia symptom and obstructive sleep apnea on their level of fatigue and quality of life than women.

A systematic approach to the development of novel therapeutics for lung cancer using genomic analyses

Molecularly targeted drugs for cancer therapy represent a therapeutic advance, but the proportion of patients who receive clinical benefit is still very limited. We present here the rationale and initial results of our program to define molecules involved in lung carcinogenesis with the goal of identifying new therapeutic targets and/or predictive biomarkers for drug response. We have used gene expression analysis of 120 lung cancers followed by RNA interference, tumor-tissue microarray analysis, and functional analyses to systematically distinguish potential target molecules specifically expressed in cancer cells. Through this approach, we have identified oncoproteins that provide the starting point for the development of therapeutic antibodies, dominant negative peptides, small-molecule inhibitors, and therapeutic cancer vaccines. We believe that the approach we describe should result in new molecularly targeted therapies with minimal risk of adverse events.

Phentermine, sibutramine and affective disorders

A safe and effective way to control weight in patients with affective disorders is needed, and phentermine is a possible candidate. We performed a PubMed search of articles pertaining to phentermine, sibutramine, and affective disorders. We compared the studies of phentermine with those of sibutramine. The search yielded a small number of reports. Reports concerning phentermine and affective disorders reported that i) its potency in the central nervous system may be comparatively low, and ii) it may induce depression in some patients. We were unable to find more studies on the subject; thus, it is unclear presently whether phentermine use is safe in affective disorder patients. Reports regarding the association of sibutramine and affective disorders were slightly more abundant. A recent study that suggested that sibutramine may have deleterious effects in patients with a psychiatric history may provide a clue for future phentermine research. Three explanations are possible concerning the association between phentermine and affective disorders: i) phentermine, like sibutramine, may have a depression-inducing effect that affects a specific subgroup of patients, ii) phentermine may have a dose-dependent depression-inducing effect, or iii) phentermine may simply not be associated with depression. Large-scale studies with affective disorder patients focusing on these questions are needed to clarify this matter before investigation of its efficacy may be carried out and it can be used in patients with affective disorders.

Resveratrol prevents renal lipotoxicity and inhibits mesangial cell glucotoxicity in a manner dependent on the AMPK-SIRT1-PGC1α axis in db/db mice

AIMS/HYPOTHESIS

Many of the effects of resveratrol are consistent with the activation of AMP-activated protein kinase (AMPK), silent information regulator T1 (SIRT1) and peroxisome proliferator-activated receptor (PPAR)γ co-activator 1α (PGC-1α), which play key roles in the regulation of lipid and glucose homeostasis, and in the control of oxidative stress. We investigated whether resveratrol has protective effects on the kidney in type 2 diabetes.

METHODS

Four groups of male C57BLKS/J db/m and db/db mice were used in this study. Resveratrol was administered via gavage to diabetic and non-diabetic mice, starting at 8 weeks of age, for 12 weeks.

RESULTS

The db/db mice treated with resveratrol had decreased albuminuria. Resveratrol ameliorated glomerular matrix expansion and inflammation. Resveratrol also lowered the NEFA and triacylglycerol content of the kidney, and this action was related to increases in the phosphorylation of AMPK and the activation of SIRT1-PGC-1α signalling and of the key downstream effectors, the PPARα-oestrogen-related receptor (ERR)-1α-sterol regulatory element-binding protein 1 (SREBP1). Furthermore, resveratrol decreased the activity of phosphatidylinositol-3 kinase (PI3K)-Akt phosphorylation and class O forkhead box (FOXO)3a phosphorylation, which resulted in a decrease in B cell leukaemia/lymphoma 2 (BCL-2)-associated X protein (BAX) and increases in BCL-2, superoxide dismutase (SOD)1 and SOD2 production. Consequently, resveratrol reversed the increase in renal apoptotic cells and oxidative stress, as reflected by renal 8-hydroxy-deoxyguanosine (8-OH-dG), urinary 8-OH-dG and isoprostane concentrations. Resveratrol prevented high-glucose-induced oxidative stress and apoptosis in cultured mesangial cells through the phosphorylation of AMPK and activation of SIRT1-PGC-1α signalling and the downstream effectors, PPARα-ERR-1α-SREBP1.

CONCLUSIONS/INTERPRETATION

The results suggest that resveratrol prevents diabetic nephropathy in db/db mice by the phosphorylation of AMPK and activation of SIRT1-PGC-1α signalling, which appear to prevent lipotoxicity-related apoptosis and oxidative stress in the kidney.

Novelty-seeking and avoidant coping strategies are associated with academic stress in Korean medical students

High levels of stress and depression in medical students is raising concern. In this study, we sought to identify coping strategies and other factors influencing academic stress in medical students. We enrolled 157 students from the University of Ulsan College of Medicine, Korea, in November, 2010. We used the Medical Stress Scale, Temperament and Character Inventory, Hamilton Depression Scale, Beck Depression Inventory, and Coping Response Inventory to assess psychological parameters. We used Pearson's correlation and linear regression analyses to analyze the data. Novelty-seeking, self-directedness, cooperativeness, coping strategy, and depression scale scores all correlated significantly with stress level. Linear regression analysis indicated that students who are novelty-seeking, likely to use avoidant coping strategies, and unlikely to use active-cognitive and active-behavioral strategies tend to have higher stress levels. Reduction of stress in medical students may be achieved through evaluation of coping strategies and personality features and use of interventions to promote active coping strategies.

The effect of initial duloxetine dosing strategy on nausea in korean patients with major depressive disorder

OBJECTIVE

To assess the relative severity of nausea in patients from Korea with major depressive disorder (MDD) who were treated with duloxetine at low (30 mg) or high (60 mg) doses, with or without food, for the first week of an 8 week treatment.

METHODS

Adult patients (n=249), with MDD and a 17-item Hamilton Rating Scale for Depression (HAMD(17)) score of ≥15, received open-label once daily duloxetine. At Week 0, patients were randomized to 4 groups: 30 mg with food (n=63), 60 mg with food (n=59), 30 mg without food (n=64), and 60 mg without food (n=63). At Week 1, all patients switched to duloxetine 60 mg for 7 weeks. The primary outcome measure was item 112 (nausea) of the Association for Methodology and Documentation in Psychiatry adverse event scale. Effectiveness was assessed by change in HAMD(17) total score.

RESULTS

Overall, 94.4% (235/249) of patients completed Week 1 and 55.0% (137/249) of patients completed the study. For Week 1, nausea was significantly less severe for patients who received 30 mg compared with 60 mg duloxetine (p=0.003), regardless of food intake. In all groups, nausea severity was highest at Week 1 and declined throughout the study. HAMD(17) score was reduced in all groups and the most common adverse event reported was nausea (145/249; 58.2%).

CONCLUSION

To minimize nausea, Korean patients with MDD who require duloxetine treatment could be given 30 mg once daily, regardless of food, for the first week followed by 60 mg once daily for the course of therapy.

Changes of Reflex, Non-reflex and Torque Generation Properties of Spastic Ankle Plantar Flexors Induced by Intelligent Stretching

Spasticity, contracture, and muscle weakness are major sources of disability in stroke. Changes of torque-generating capacity as well as reflex and non-reflex properties of ankle plantar flexors induced by strenuous stretching in chronic hemiplegia were investigated. Twelve subjects with a unilateral stroke and 10 healthy controls underwent 30 minutes of strenuous intelligent stretching treatment. Reflex and non-reflex components of spastic hypertonia and force-generating capacity of ankle plantar flexors were investigated. Dorsiflexion (DF) range of motion (ROM) was increased (p=0.002) and passive stiffness and passive resistant torque of the spastic muscles were decreased (p=0.004 and 0.007, respectively), while reflex hyper-excitability diminished slightly but with no statistical significance. The maximal voluntary contraction (MVC) torque of the spastic ankle plantar flexors was increased after the forceful stretching treatment (p=0.041). In contrast, the stretching treatment of the healthy plantar flexors did not change any of the variables measured before and after stretching. The stroke subjects who gained more DF ROM or larger decrement of stiffness achieved greater increment of the peak torque generation after the stretching (r=0.597 with p=0.040 and r=-0.746 with p=0.005, respectively). These results suggest that the strenuous dynamic stretching could improve the force-generating capacity of spastic muscles as well as reduce the passive stiffness and increase ROM.

The mean intensity ofo activation than the number of activated voxels is a better index to reflect the levels of visuospatial performance

This study is to identify the more sensitive method to measure the brain activation by the visuospatial performance level by comparing two different methods of measuremtnt (i.e., a method calculating the number of activated voxels and the other, the mean intensity of activated voxels). Sixteen right-handed male college students (mean age 23.2 years) participated in this study and function brain images were scanned with a 3T MRI using the single-shot EPI method during visuospatial performance. There found no brain areas with correlation between the visuospatial performance level and number of activated voxels. However, there found a sifgnificant correlatgion between the visuospatial performance level and the mean intensity of selected activated voxels in the parietal, frontal, and other areas.f In conclusion, the method of meanintensity rather than the one of the number is considered as a better index.

What can be learned about the impact of diabetes on hospital admissions from routinely recorded data?

AIM

To determine whether inpatients with diabetes have different lengths of stay, day-case listing rates or emergency readmission rates compared with those without diabetes receiving similar treatment.

METHOD

English 2007-2008 Hospital Episode Statistics were analysed alone and after linkage to the 1.6 million people included in the 2007-2008 English National Diabetes Audit. Length of stay, day-case listing rates and emergency readmission rates were compared between those with and without diabetes by Health Resource Group chapter. Using univariate and multivariate statistics, the potential influences of age, sex, social deprivation, type and complexity of admission were considered.

RESULTS

Of all inpatient spells in Hospital Episode Statistics, 6.2% have diabetes coded at discharge. Substantial under-recording of diabetes has been identified-a further 3% of inpatient spells involve people with diabetes. Inpatients with recorded diabetes stay in hospital for 100% longer on average, are 50% less likely to be treated as day cases and are almost 100% more likely to be readmitted as an emergency. The adverse impact of diabetes on length of stay was similar to that for chronic obstructive pulmonary disease. Most of this adverse effect was in patients coded with diabetes in Hospital Episode Statistics. Multivariate statistical analysis showed that diabetes is independently associated with increased length of stay. The effect differed up to threefold between hospitals.

CONCLUSIONS

Diabetes has an independent adverse effect on key aspects of hospital inpatient stays. If the lowest levels of adverse impact on inpatients with diabetes were more common, substantial cost savings and improved experience of care would be realized.

A structural model of stress, motivation, and academic performance in medical students

OBJECTIVE

The purpose of the present study was 1) to identify factors that may influence academic stress in medical students and 2) to investigate the causal relationships among these variables with path analysis.

METHODS

One hundred sixty medical students participated in the present study. Psychological parameters were assessed with the Medical Stress Scale, Minnesota Multiphasic Personality Inventory, Hamilton Depression Scale, Beck Depression Inventory, and Academic Motivation Scale. Linear regression and path analysis were used to examine the relationships among variables.

RESULTS

Significant correlations were noted between several factors and Medical Stress scores. Specifically, Hamilton Depression Scale scores (β=0.26, p=0.03) and amotivation (β=0.20, p=0.01) and extrinsically identified regulation (β=0.27, p<0.01) response categories on the Academic Motivation Scale had independent and significant influences on Medical Stress Scale scores. A path analysis model indicated that stress, motivation, and academic performance formed a triangular feedback loop. Moreover, depression was associated with both stress and motivation, and personality was associated with motivation.

CONCLUSION

The triangular feedback-loop structure in the present study indicated that actions that promote motivation benefit from interventions against stress and depression. Moreover, stress management increases motivation in students. Therefore, strategies designed to reduce academic pressures in medical students should consider these factors. Additional studies should focus on the relationship between motivation and depression.

The influence of personality and dysfunctional sleep-related cognitions on the severity of insomnia

Previous findings suggest that personality traits and dysfunctional sleep-related cognitions may perpetuate insomnia, but findings concerning this have been scarce. Thus, we hypothesized that personality and sleep-related cognitions influence the severity of insomnia, and investigated the association personality and sleep-related cognitions had with various sleep-related parameters, including severity of insomnia. Forty-four patients with psychophysiological insomnia were assessed using The Temperament and Character Inventory, the Insomnia Severity Index, the Pittsburgh Sleep Quality Index, the Epworth Sleepiness Scale, the Dysfunctional Belief and Attitudes toward Sleep Scale, the Pre-Sleep Arousal Scale and the Hospital Anxiety and Depression Scale. Insomnia severity was significantly and positively correlated with harm avoidance, self-transcendence and sleep-related cognitions, and negatively correlated with novelty seeking, reward dependence, and cooperativeness. Dysfunctional sleep-related cognitions were positively correlated with insomnia severity and sleep quality. Stepwise multiple regression analysis showed that sleep-related cognitions, depression and reward dependence scores were significant determinants of insomnia severity, and that sleep-related cognitions and self-transcendence were significant positive determinants of sleep quality. Reward dependence, depression and sleep-related cognitions were associated with insomnia severity, and comparison with previous findings implied that 'internalizing behavior' and depression may be more plausible candidates for the link between personality and insomnia than anxiety. Considering the major role of cognitive-behavioral treatment (CBT) in the treatment of insomnia, assessment of these factors and management of sleep-related cognitions may help alleviate symptoms in patients with insomnia.

Comparison of three actigraphic algorithms used to evaluate sleep in patients with obstructive sleep apnea

PURPOSE

Actigraphy is a non-invasive and valid method to detect sleep/wake status. However, the technique lacks reliability in patients with sleep-disordered breathing and its results may depend on the algorithm employed.

METHODS

We compared three currently used algorithms (the Cole-Kripke, Sadeh, and University of California San Diego [UCSD]) and determined which is the most reliable in patients with obstructive sleep apnea (OSA) assessing total sleep time. After identification of the most reliable algorithm, we compared total sleep time with the severity of obstructive sleep apnea.

RESULTS

The mean total sleep time was not significantly different from that yielded by polysomnography when the UCSD algorithm was employed (p = 0.798) and UCSD algorithm was associated with the smallest bias. The correlation levels (with polysomnographic data) were mild-to-modest when the results yielded by all algorithms were evaluated, but were highest when the UCSD algorithm was employed (UCSD, r = 0.498, p < 0.001; Cole-Kripke, r = 0.389, p < 0.01; Sadeh, r = 0.272, p = 0.057). Actigraphic measures of mean total sleep time underestimated sleep in patients with severe obstructive sleep apnea (apnea-hypopnea index [AHI] ≥30), and the correlation was low (r = 0.317, p = 0.116), but overestimated sleep, with high correlations, in patients with mild (5 ≤ AHI < 15) and moderate OSA (15 ≤ AHI < 30; r = 0.859, p < 0.001; r = 0.842, p < 0.001, respectively).

CONCLUSIONS

Among the three actigraphic algorithms tested in this study, sleep duration estimated by the UCSD algorithm was the most correlated with polysomnography data in an OSA population. However, none of them was reliable enough for estimating sleep time in patients with sleep-disordered breathing, especially in patients with severe OSA.