Association between sleep quality and type 2 diabetes at 20-year follow-up in the Southall and Brent REvisited (SABRE) cohort: a triethnic analysis

Background

The risk of developing type 2 diabetes associated with poor sleep quality is comparable to other lifestyle factors (eg, overweight, physical inactivity). In the UK, these risk factors could not explain the two to three-fold excess risks in South-Asian and African-Caribbean men compared with Europeans. This study investigates (1) the association between mid-life sleep quality and later-life type 2 diabetes risk and (2) the potential modifying effect of ethnicity.

Methods

The Southall and Brent REvisited cohort is composed of Europeans, South-Asians and African-Caribbeans (median follow-up 19 years). Complete-case analysis was performed on 2189 participants without diabetes at baseline (age=51.7±7 SD). Competing risks regressions were used to estimate the HRs of developing diabetes associated with self-reported baseline sleep (difficulty falling asleep, early morning waking, waking up tired, snoring and a composite sleep score), adjusting for confounders. Modifying effects of ethnicity were analysed by conducting interaction tests and ethnicity-stratified analyses.

Results

There were 484 occurrences of incident type 2 diabetes (22%). Overall, there were no associations between sleep exposures and diabetes risk. Interaction tests suggested a possible modifying effect for South-Asians compared with Europeans for snoring only (p=0.056). The ethnicity-stratified analysis found an association with snoring among South-Asians (HR 1.41, 95% CI 1.08 to 1.85), comparing those who snored often/always versus occasionally/never. There were no elevated risks for the other sleep exposures.

Conclusion

The association between snoring and type 2 diabetes appeared to be modified by ethnicity, and was strongest in South-Asians.

Status and disparities of diabetes among urban and rural residents aged 40 years and older: insight from a population-based study in northeast China, 2017-2019

OBJECTIVES

To evaluate the up-to-date epidemiology of diabetes in northeast China.

METHODS

The cross-sectional study was conducted between September 2017 and March 2019 using a multistage, stratified and cluster random sampling method. 18 796 participants (28.9% urban and 71.1% rural) aged ≥40 years were enrolled. Diabetes and pre-diabetes were diagnosed according to the history, fasting plasma glucose (FPG) and glycosylated haemoglobin A1c (HbA1c) levels.

RESULTS

The prevalence of diabetes was 17.1%, higher in urban than in rural residents (20.2% vs 15.8%, p<0.001). Meanwhile, the prevalence of pre-diabetes was 44.3%, higher in rural than in urban areas (49.4% vs 31.8%, p<0.001). The overall FPG and HbA1c were 6.10±1.94 mmol/L and 5.59%±1.08%. The FPG level was higher in rural area than in urban areas (6.15±1.83 mmol/L vs 5.97±2.18 mmol/L, p<0.001). Among participants with diabetes, 47.5% were aware of their diabetes condition; 39.5% were taking antidiabetic medications and 36.8% of people had their diabetes controlled. The awareness and treatment rates in rural areas were lower than those in urban areas (47.3% vs 57.5%, 34.4% vs 49.5%, p<0.001). Patients with diabetic, especially those in rural areas, tended to have multiple risk factors including hypertension (71.7%), overweight or obesity (69.6%) and dyslipidaemia (52.8%).

CONCLUSION

A considerable burden of diabetes was observed in northeast China, with high percentage of untreated diabetes, high prevalence of pre-diabetes, high overall FPG level and multiple uncontrolled risk factors in patients with diabetics. Therefore, region-specific strategies on prevention and management of diabetes should be emphasised.

Onset of type 1 diabetes mellitus in rural areas of the USA

BACKGROUND

In the USA, the epidemiologic features of type 1 diabetes are not well-defined across all 50 states. However, the advent of large nationwide insurance databases enables the investigation of where type 1 diabetes cases occur throughout the country.

METHODS

An integrated database from a large nationwide health insurer in the USA (Clinformatics Data Mart Database) was used, from 2001 to 2017. The database contained longitudinal information on approximately 77 million people.

RESULTS

The incidence of type 1 diabetes was greatest in areas of low population density across the 50 states. Individuals in the lowest population density areas had rates that were 2.28 times (95% CI 2.08 to 2.50) that of persons living in high-density areas. This association was consistent across various measures of rural status (p<0.001 for population density; p<0.001 for per cent rural as defined by the US Census Bureau; p=0.026 for farmland). The association between rural areas and the incidence of type 1 diabetes was evident across all four general regions of the USA.

CONCLUSIONS

The predilection of type 1 diabetes in rural areas provides clues to potential factors associated with the onset of this autoimmune disease.

Waist circumference threshold values for type 2 diabetes risk

Adult gains in body weight, excess adiposity, and intra-abdominal fat have each been associated with risk for type 2 diabetes mellitus (T2DM), forming the basis for preventive medicine guidelines and actuarial predictions using practical indices of weight (e.g., body mass index [BMI]) and waist circumference (WC). As obesity-related disease spreads beyond affluent western countries, application of WC thresholds to other populations has highlighted issues of their generalizability. For example, U.S. national health goals based on BMI < 25 kg/m(2) and WC < 89 cm (women) and <102 cm (men) differ considerably with a recent law in Japan mandating intervention for older adults with WC exceeding 90 cm (women) and 85 cm (men). The U.S. military has also faced issues of generalizability of WC-based adiposity standards that are fair and achievable. Data from many studies indicate that WC is a reliable biomarker for T2DM risk, suggesting that, for adult men and women, action thresholds should be more stringent than current U.S. guidelines, and it would not be harmful to set worldwide targets somewhere below 90 cm for men and women, regardless of weight status. Medical technology has provided many great insights into disease, including modern imaging technologies that have differentiated fat depots that have the greatest influence on T2DM, but ultimately, an inexpensive measuring tape provides the most useful and cost-effective preventive measure for T2DM today. At some point in the future, a Star Trek-like abdominal body fat "tricorder" noninvasive assessment of tissue composition may provide an advantage over abdominal girth.