100,000 Chinese research data: TA, who often accompanies workers off work, can increase the risk of diabetes by 28%!

Exposure to outdoor artificial light from a variety of light sources at night is a prevalent environmental risk factor
in modern society.
Urban light pollution affects not only residents of large cities, but also residents of suburban and remote areas such as forest parks hundreds of kilometers away from the light source
.
Although more than 80% of the world's population is exposed to light pollution at night, it is only in recent years that the issue has received limited attention
from scientists.

Diabetes is a serious public health problem
in China.
The onset and progression of diabetes are largely due to behavioural and environmental risk factors
.
With the rapid development of urbanization and economy, China's urban artificial lighting has greatly increased
.
People living in cities are more likely to move from nature's 24-hour circadian rhythm to a model
of round-the-clock work, staying up late, and being exposed to artificial LANs.
Therefore, it is essential to assess the extent to which artificial LAN causes or is associated with diabetes in order to implement effective prevention strategies
.
This study aimed to estimate the relationship between long-term exposure to outdoor artificial LAN, glucose homeostasis markers and diabetes prevalence based on national and cross-sectional surveys of the general population in China.

The China NCD Surveillance Study is a nationally representative study that included 98,658 participants aged ≥18 years who had lived in their current residence for at least 6 months in 2010 from 162 study sites in Chinese mainland, and diabetes was defined
according to ADA criteria.
The association between outdoor LAN exposure levels and the presence of diabetes, household income, urban/rural areas, taking antihypertensive drugs, taking lipid-lowering drugs, and BMI
was assessed by calculating prevalence (PRs) and adjusting for age, sex, education, smoking status, alcohol consumption status, physical activity, family history of diabetes.

The results showed that the radiation exposed to the LAN varied widely
across China.
Most areas are exposed to low-intensity outdoor LANs, while higher outdoor LAN intensities are concentrated in eastern coastal cities
.
In a further analysis, the researchers classified
participants by quintile of outdoor LAN exposure.
The median outdoor LAN (IQR) from quintile 1 to quintile 5 was 1.
0 (0.
6, 1.
7), 3.
9 (3.
2, 4.
8), 7.
0 (6.
3, 8.
1), 17.
0 (10.
5, 24.
5), and 69.
1 (53.
9, 117.
0) nW cm−2 sr−1, respectively
。

The mean age of the study population was 42.
7 years, and 53,515 participants (weighted ratio 49.
2%) were women
.
The researchers examined the shape
of the exposure-response curve in the relationship between outdoor LAN exposure and glucose homeostasis markers and diabetes.
Outdoor LAN exposure levels were positively correlated with HbA1c, fasting and 2-hour glucose concentrations, and HOMA-IR, and negatively correlated
with HOMA-B.
The prevalence of diabetes was significantly associated with LAN exposure per quintile (PR 1.
07 [95% CI 1.
02 to 1.
12]).

LAN exposure was the highest quintile (median 69.
1 nW cm−2 sr−1) and lowest quintile exposure (median 1.
0 nW cm−2 sr−1).
The prevalence of diabetes was significantly increased (PR 1.
28 [95% CI 1.
03 to 1.
60]).

Overall, there was a significant correlation
between long-term exposure to high-intensity outdoor LAN and an increased risk of glucose metabolism disorders and diabetes prevalence.
The results of this study further confirm the growing body of evidence that LAN is harmful to health and point to outdoor LAN as a potential new risk factor
for diabetes.

Original source:

Zheng R, Xin Z, Li M, Wang T, Xu M, Lu J, Dai M, Zhang D, Chen Y, Wang S, Lin H, Wang W, Ning G, Bi Y, Zhao Z, Xu Y.
Outdoor light at night in relation to glucose homoeostasis and diabetes in Chinese adults: a national and cross-sectional study of 98,658 participants from 162 study sites.
Diabetologia.
2022 Nov 14.
doi: 10.
1007/s00125-022-05819-x.
Epub ahead of print.
PMID: 36372821.