Reduced Sleep Duration or Quality: Relationships With Insulin Resistance and Type 2 Diabetes

Altered sleep parameters, such as duration and quality, play an important role in the pathogenesis and progression of cardiovascular diseases, as well as in all-cause morbidity and mortality. It has been suggested that the specific mechanisms underlying this association could be through the influence of sleep parameters on vascular markers, such as arterial stiffness (AS), although this remains unclear. Thus, in this meta-analysis, we aimed to assess the association between sleep duration and sleep quality with AS in adults.

PubMed, Scopus, Web of Science and Cochrane Library databases were searched from inception to July 30, 2021. The DerSimonian and Laird method was used to compute pooled effect size estimates and their respective 95% confidence intervals (95% CIs) of the association of sleep duration and sleep quality with AS. The Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies from the United States National Institute of Health National Heart, Lung, and Blood Institute was used to assess the risk of bias.

Finally, 14 studies (8 cross-sectional studies and baseline data from 6 prospective longitudinal studies) involving 97,837 individuals between 18 and 92 years of age were included. Our results showed that increased sleep duration, as continuous values, does not influence AS (effect size [ES]: 0.00; 95% CIs: -0.15, 0.15) in the general population. However, when sleep duration was longer than 8 hours (ES: 0.21; 95% CIs: 0.06, 0.36), according to sleep categories, a significant increase in pulse wave velocity was shown. Poor sleep quality was associated with increased AS (ES: 0.13; 95% CIs: 0.04, 0.21) in the general population. The overall risk of bias for studies examining sleep duration was fair in 77.8% of the included studies and the overall risk of bias for studies examining sleep quality was fair in 55.6%.

Our findings showed that both long sleep duration and poor sleep quality were associated with AS in adults. These findings underscore the influence of sleep on vascular health markers, specifically AS, as a possible pathway to explain the increased cardiovascular morbidity and mortality associated with sleep disorders.

La diabetes tipo 2 (DM2) es una de las enfermedades que causa mayor mortalidad prematura y discapacidad a nivel mundial. Las alteraciones del sueño se han asociado a la aparición de trastornos metabólicos y a mayores niveles de hemoglobina glucosilada en personas diabéticas.

Evaluar la calidad del sueño de personas con DM2 y su asociación con características sociodemográficas, clínicas y metabólicas.

Estudio observacional, transversal, analítico en 223 personas con DM2 entre 20 y 64 años controladas en un centro de atención primaria de salud.

La mayoría eran mujeres (66,4%), edad promedio 54,7 años y solo el 33% duerme las horas necesarias (7 a 9 horas). Un 57,7% se encontraba metabólicamente descompensado (Hb1Ac > 7%). Un 75,2% de los participantes presentó problemas de sueño de diversa gravedad, que se asoció a ser mujer, dolor nocturno, nicturia, tiempo de diagnóstico de la diabetes y síntomas depresivos. Las personas con mala calidad de sueño tuvieron 73% más probabilidad de estar descompensados metabólicamente, sin embargo, este resultado no fue estadísticamente significativo OR = 1,73 (IC: 0,78-3,87).

Destaca la alta frecuencia de mala calidad de sueño y descompensación metabólica en la muestra, lo que podría complicar la DM2. No es concluyente la asociación entre mala calidad de sueño y descompensación de la DM2. Futuras investigaciones contribuirán a dilucidar el papel del sueño en la compensación metabólica y en la prevención de trastornos metabólicos.

Type 2 diabetes (DM2) is one of the diseases that cause the highest premature mortality and disability worldwide. Sleep disturbances have been associated with the onset of metabolic disorders and increased levels of glycated haemoglobin in diabetics.

To evaluate the quality of sleep of people with type 2 diabetes and its association with sociodemographic, clinical, and metabolic characteristics.

Observational, cross-sectional, analytical study of 223 patients with DM2 between 20 and 64 years old, controlled in a primary health care centre in Chile.

Most were women (66.4%), average age 54.7 years. Only 33% slept the required number of hours (7 to 9 hours) to maintain health. Fifty-seven point seven percent were metabolically unbalanced (Hb1Ac > 7%). Seventy-five point two percent presented sleep problems of varying severity, which were associated with being a woman, night pain, nocturia, time of diagnosis of diabetes, and depressive symptoms. Persons with poor sleep quality were 73% more likely to be metabolically decompensated, however, this result was not statistically significant: OR = 1.73 (CI:78-3.87).

The high frequency of poor sleep quality and metabolic decompensation in the sample stands out, which could complicate DM2. The association between poor sleep quality and DM2 decompensation is inconclusive. Future research will contribute to elucidating the role of sleep in metabolic compensation and in the prevention of metabolic disorders.

The primary aim of the study was to estimate the effect of sleep duration on prospective type 2 diabetes (T2D) risk across demographic characteristics and follow-up periods, and test body mass index (BMI) as a mediator and moderator.

Data included adults (M_age = 39.0 ± 12.7 years) born in the United States or Mexico recruited from 2001 to 2012 in a Mexican American cohort study conducted in Houston, TX (n = 15,779). Participants completed self-reported questionnaires at baseline related to health, health behaviors (sleep duration, physical activity, smoking, drinking), and sociocultural factors and were followed up annually.

Cox proportional hazard models estimated hazard ratios (HR) for the effect of sleep duration on T2D diagnosis at follow-up. Of the participants, 10.3% were diagnosed with T2D. Self-reported ≤5 hours of sleep, compared to 7-8 hours, at baseline predicted greater risk for T2D (HR = 1.32, P = .001), yet was no longer significant after adjusting for sociodemographic characteristics and BMI. Notably, those with BMI <25 kg/m² reporting ≤5 hours of sleep were at significant risk for T2D at 3 (HR = 4.13, P = .024) and 5-year follow-up (HR = 3.73, P = .008) compared to 7-8 hours. Obesity status accounted for 31.6% and 27.3% of the variance in the association between ≤5 and 6 hours of sleep and increased T2D risk, respectively.

Results highlighted the mediating and moderating role of BMI, and its effect on T2D risk at earlier follow-up among those without obesity. T2D prevention and control for Mexican American adults should consider the role of chronic sleep loss.