Short sleep duration predicts risk of metabolic syndrome: a systematic review and meta-analysis

Sleep duration has been suggested to play a key role in the development of metabolic syndrome (MS). However, the results have been inconsistent. The objective of this study was to clarify the association between sleep duration and MS risk. PubMed and Embase databases were searched for eligible publications. Pooled odds ratio (OR) with 95% confidence interval (CI) was calculated using random- or fixed-model. A total of 12 studies (18,720 MS cases and 70,833 controls) were included in the meta-analysis. Short sleep duration was significantly associated with increased risk of MS (OR = 1.27, 95%CI = 1.09-1.47, p = 0.002). Long sleep duration was not associated with increased risk of MS (OR = 1.07, 95%CI = 0.87-1.32, p = 0.535). Similar results were found in both men and women. The sensitivity analysis confirmed the stability of the results and no publication bias was detected. The present meta-analysis suggests that short rather than long sleep duration is significantly associated with risk of MS. Large-scale well-design prospective studies are required to further investigate the association between sleep duration and MS risk.

Sleep duration and metabolic syndrome in adult populations: a meta-analysis of observational studies

OBJECTIVE

Epidemiological studies have repeatedly investigated the association between sleep duration and metabolic syndrome. However, the results have been inconsistent. This meta-analysis aimed to summarize the current evidence from cross-sectional and prospective cohort studies that evaluated this.

DATA SOURCES

Relevant studies were identified by systematically searching the PubMed, Cochrane CENTRAL, EMBASE and PsycINFO databases through November 2012 without language restriction.

STUDY SELECTION

We identified 12 cross-sectional studies with 76 027 participants including 14 404 cases of metabolic syndrome, and 3 cohort studies with 2055 participants and 283 incident cases of metabolic syndrome.

RESULTS

For short sleep durations (<5 to 6 h), the odds ratios (OR) was 1.27 (95% confidence interval (CI)=1.10-1.48, I(2)=75.5%) in the 12 cross-sectional studies and 1.62 (95% CI=0.74-3.55, I(2)=71.4%) in the 3 cohort studies; for long sleep durations (>8 to 10 h), the OR was 1.23 (95% CI=1.02-1.49, I(2)=75.8%) in the 11 cross-sectional studies and 1.62 (95% CI=0.86-3.04, I(2)=0.0%) in the 2 cohort studies.

CONCLUSIONS

Short and long sleep durations are risky behaviors for increasing the risk of metabolic syndrome and thus have important public health implications, as sleep habits are amenable to behavioral interventions. The available data are sparse, and further studies, especially longitudinal studies, are needed to facilitate a better understanding of these associations.

Assessment of insomnia and related risk factors in postmenopausal women screened for the metabolic syndrome

BACKGROUND

Sleep disturbances are common during female mid-life. Nevertheless, there is limited available information linking sleep characteristics to the menopause and the metabolic syndrome (METS).

OBJECTIVE

To assess insomnia prevalence and related risk factors in postmenopausal women screened for the METS.

METHODS

In this cross sectional study 204 natural postmenopausal women participating in a METS screening program filled out the Athens insomnia scale (AIS), the hospital anxiety and depression scale (HADS) and a general socio-demographic questionnaire. Criteria of the Adult Treatment Panel III (ATP-III) were used to define the METS.

RESULTS

Median age of the whole sample was 56 years. A 50.5% of women had the METS, 57.4% hot flushes, 58.3% were abdominally obese, 51.5% hypertension, 25.0% hyperglycemia, 15.7% depressed mood and 29.9% anxiety. A 33.8% presented insomnia according to the AIS (scores 6 or more). The AIS displayed a high internal consistency as computed Cronbach's alpha was determined to be 0.86. Multiple linear regression analysis determined that male premature ejaculation, female psychotropic drug use, hot flush intensity, mood morbidity (higher total HADS scores) and higher parity positively and significantly correlated to higher AIS scores (more insomnia).

CONCLUSION

In this postmenopausal sample insomnia was not related to the METS or its components yet to other psycho-somatic female and partner issues.

Short sleep duration associated with a higher prevalence of metabolic syndrome in an apparently healthy population

OBJECTIVE

To examine the association between sleep duration and metabolic syndrome in an apparently healthy Chinese population.

METHOD

The baseline data were collected from a health examination center in Tainan, Taiwan, from October 1, 2006, to August 31, 2009. A total of 7100 adults were recruited. Subjects were classified into three groups according to their sleep duration: short (<6 h), normal (6-8 h), and long sleepers (>8 h).

RESULTS

There were significant differences in age, gender, education level, fasting plasma glucose, and the proportion of smoking status and exercise frequency among different sleep groups. Based on multiple logistic regression, short sleepers were positively associated with metabolic syndrome (OR=1.28, 95% CI: 1.01-1.63) in males but not in females (OR=1.04, 95% CI: 0.72-1.51). Long sleepers were not related with metabolic syndrome in both genders. Short sleep duration was independently related to hyperglycemia (OR=1.39, 95% CI: 1.10-1.74) also in males only. Other components such as hypertriglyceridemia, low high density lipoprotein cholesterol, high blood pressure and central obesity were not associated with short sleep duration.

CONCLUSION

Males with short sleep duration are positively associated with metabolic syndrome and they also exhibited a higher prevalence of hyperglycemia.

Sleep deprivation is associated with lower diet quality indices and higher rate of general and central obesity among young female students in Iran

OBJECTIVES

Short sleep duration and low diet quality are associated with weight gain. However, little is known about the relationship between sleep duration and the quality of diets. Therefore, we aimed to compare the diet quality indices and anthropometric measures between short and longer sleepers.

METHODS

This cross-sectional study consisted of 410 female youths who were chosen among students of Isfahan University of Medical Sciences based on stratified random sampling method. Dietary intake assessment was done using a semiquantitative validated food frequency questionnaire. Sleep duration was estimated using self-reported nocturnal sleep duration by each person. Anthropometric measures were done using standard protocols. Diet quality indices (including dietary energy density, dietary diversity scores, healthy eating index, nutrient adequacy ratio, and mean adequacy ratio) were calculated using the standard definition.

RESULTS

Subjects who slept less than 6 h/d were more likely to be overweight and obese (P = 0.0001) and also abdominally obese (P = 0.03). They also consumed more dietary energy (2406 ± 825 versus 2092 ± 700 kcal/d; P = 0.01, respectively) and carbohydrates (58.1 ± 16.2% versus 51.6 ± 10.3%; P = 0.03) but a lower amount of fiber (12 ± 7 versus 18 ± 7 g/d; P = 0.04), fruits (2.4 ± 0.6 versus 3.1 ± 0.7 servings/d; P = 0.04), whole grains (0.9 ± 0.1 versus 1.3 ± 0.1 servings/d; P = 0.04), and beans (0.3 ± 0.1 versus 0.8 ± 0.1 servings/d; P = 0.04). All diet quality indices were significantly lower among short sleepers (P < 0.05), apart from dietary energy density, which did not differ significantly (P = 0.8).

CONCLUSION

Our findings confirm the association of short sleep duration and obesity in young female youths. It might be derived from lower diet quality among short sleepers more than longer sleepers.

Short sleep duration is associated with hypertension risk among adults: a systematic review and meta-analysis

A number of studies have reported that sleep duration might have an important role in the development of hypertension. However, the results have been inconsistent. In this study, a meta-analysis was performed to clarify the association between sleep duration and hypertension risk. PubMed, Embase and ISI web of science databases updated on 28 October 2011 were searched for eligible publications. Pooled odds ratio (OR) or relative risk (RR) with 95% confidence intervals (CI) was calculated using a random- or fixed-effect model. Six prospective (N=9959) and seventeen cross-sectional (N=105432) studies were identified for the data analysis on sleep duration. The results indicated that short sleep duration was associated with an increased risk of prevalent hypertension (OR=1.20, 95% CI: 1.09-1.32, P<0.001), especially among subjects younger than 65 years and females. In addition, short sleep duration was also associated with an increased risk of incident hypertension among subjects younger than 65 years (RR=1.33, 95% CI: 1.11-1.61, P=0.002). Overall, there was a significant association between long sleep duration and the risk of prevalent hypertension (OR=1.11, 95% CI: 1.05-1.17, P<0.001). Further subgroup analysis also suggested a significant association between long sleep duration and the risk of prevalent hypertension among subjects younger than 65 years (OR=1.12, 95% CI: 1.06-1.19, P<0.001). The present meta-analysis indicated that short sleep duration was associated with an increased risk of hypertension in the overall polulation and incident hypertension among subjects younger than 65 years. In addition, long sleep duration might be associated with a risk of prevalent hypertension, especially among subjects younger than 65 years.

Might psoriasis be a risk factor for obstructive sleep apnea syndrome?

BACKGROUND

It is believed that psoriasis is a chronic systemic inflammatory disease. Obstructive sleep apnea syndrome (OSAS) is a disease influencing all systems and characterized by intermittent partial or complete obstruction of the upper respiratory tract during sleep. In our study, we aimed to investigate the frequency of OSAS in patients previously diagnosed with psoriasis in order to investigate a potential association between chronic inflammation psoriasis and OSAS.

METHODS

Thirty-three patients diagnosed with psoriasis by biopsy were enrolled into the study. Demographics of patients, Psoriasis Area Severity Index (PASI), Dermatology Life Quality Index (DLQI), and Epworth Sleepiness Scale were examined. All patients underwent polysomnography.

RESULTS

OSAS was determined in 18 of 33 patients with psoriasis (54.5 %). Eleven of the 18 patients had mild, 2 had moderate, and 5 had severe OSAS. Mean age was significantly higher in the OSAS group in comparison with non-OSAS group (54.4 ± 15.5 vs 39.4 ± 11.8, respectively, p < 0.05). Mean PASI was higher in the OSAS group in comparison with that of non-OSAS group, and the difference was not significant, although mean DLQI was lower (p > 0.05). It is believed that this was caused by the small patient population.

CONCLUSION

We detected that the frequency of OSAS in patients with psoriasis was much higher than that in the normal population. Though OSAS is not easy to diagnose without detailed testing, it should be investigated in psoriatic patients with long disease duration and high PASI score, and patients refractory to conventional systemic treatment. Physicians treating patients with psoriatic disease should incorporate this life-altering comorbidity into their assessment of disease and selection of treatment.