Profile and dynamics of infectious diseases: a population-based observational study using multi-source big data

Long-term exposure to particulate air pollution associated with the progression of type 2 diabetes mellitus in China: effect size and urban-rural disparities

BACKGROUND

Recent Western studies link long-term particulate matter (PM) exposure to type 2 diabetes mellitus (T2DM) progression, but little is known for low- and middle-income countries. This study aimed to estimate the relationship between PM exposure and T2DM progression in China, and also assess urban-rural disparities.

METHODS

Using 7-year cohort data of 1.3 million Chinese over 40, a multistate model estimated the associations of PM exposure with T2DM progression. Covariates included demographics, socioeconomic status, health behaviors, medication, and meteorological factors. Sub-sample analyses were done for rural and urban areas.

RESULTS

For participants exposed to high levels of PM 2.5 , the 5-year absolute risks of developing T2DM and its complications were 4.31% (95% CI: 4.22-4.40) and 31.04% (95% CI: 29.97-32.08), respectively. In the low- PM 2.5 -exposure group, these risks were 3.82% (95% CI: 3.74-3.91) and 30.55% (95% CI: 29.43-31.65). For each 10 µg/m3 increase in PM 2.5 exposure, the HRs (95% CI) for the progression from no T2DM diagnosis to a T2DM diagnosis were 1.13 (1.13-1.14), and for the progression from T2DM to the development of T2DM complications were 1.04 (1.03-1.06). Moreover, the HRs (95% CI) for mortality risk were 1.09 (1.08-1.09) for participants without T2DM, 1.06 (1.00-1.14) for those with T2DM, and 1.10 (1.05-1.16) for those with T2DM complications. Similar associations were observed for other PM-related metrics. In rural areas, PM exposure was more strongly associated with the progression from T2DM and its complications to death. Conversely, in urban areas, PM exposure had a stronger association with the progression from a non-T2DM state to a formal T2DM diagnosis. Urban residents are exposed to higher levels of toxic components like heavy metals, potentially increasing T2DM risk, yet urban healthcare infrastructure offers protection against T2DM-related mortality.

CONCLUSIONS

PM exposure is significantly associated with T2DM progression. Urban areas should focus on primary prevention, while rural areas need to improve secondary and tertiary prevention like healthcare services.

Urban-rural disparities in the association of nitrogen dioxide exposure with cardiovascular disease risk in China: effect size and economic burden

BACKGROUND

Together with rapid urbanization, ambient nitrogen dioxide (NO2) exposure has become a growing health threat. However, little is known about the urban-rural disparities in the health implications of short-term NO2 exposure. This study aimed to compare the association between short-term NO2 exposure and hospitalization for cardiovascular disease (CVD) among urban and rural residents in Shandong Province, China. Then, this study further explored the urban-rural disparities in the economic burden attributed to NO2 and the explanation for the disparities.

METHODS

Daily hospitalization data were obtained from an electronic medical records dataset covering a population of 5 million. In total, 303,217 hospital admissions for CVD were analyzed. A three-stage time-series analytic approach was used to estimate the county-level association and the attributed economic burden.

RESULTS

For every 10-μg/m3 increase in NO2 concentrations, this study observed a significant percentage increase in hospital admissions on the day of exposure of 1.42% (95% CI 0.92 to 1.92%) for CVD. The effect size was slightly higher in urban areas, while the urban-rural difference was not significant. However, a more pronounced displacement phenomenon was found in rural areas, and the economic burden attributed to NO2 was significantly higher in urban areas. At an annual average NO2 concentration of 10 μg/m3, total hospital days and expenses in urban areas were reduced by 81,801 (44,831 to 118,191) days and 60,121 (33,002 to 86,729) thousand CNY, respectively, almost twice as much as in rural areas. Due to disadvantages in socioeconomic status and medical resources, despite similar air pollution levels in the urban and rural areas of our sample sites, the rural population tended to spend less on hospitalization services.

CONCLUSIONS

Short-term exposure to ambient NO2 could lead to considerable health impacts in either urban or rural areas of Shandong Province, China. Moreover, urban-rural differences in socioeconomic status and medical resources contributed to the urban-rural disparities in the economic burden attributed to NO2 exposure. The health implications of NO2 exposure are a social problem in addition to an environmental problem. Thus, this study suggests a coordinated intervention system that targets environmental and social inequality factors simultaneously.

Comorbidity increases the risk of pulmonary tuberculosis: a nested case-control study using multi-source big data

BACKGROUND

Some medical conditions may increase the risk of developing pulmonary tuberculosis (PTB); however, no systematic study on PTB-associated comorbidities and comorbidity clusters has been undertaken.

METHODS

A nested case-control study was conducted from 2013 to 2017 using multi-source big data. We defined cases as patients with incident PTB, and we matched each case with four event-free controls using propensity score matching (PSM). Comorbidities diagnosed prior to PTB were defined with the International Classification of Diseases-10 (ICD-10). The longitudinal relationships between multimorbidity burden and PTB were analyzed using a generalized estimating equation. The associations between PTB and 30 comorbidities were examined using conditional logistic regression, and the comorbidity clusters were identified using network analysis.

RESULTS

A total of 4265 cases and 17,060 controls were enrolled during the study period. A total of 849 (19.91%) cases and 1141 (6.69%) controls were multimorbid before the index date. Having 1, 2, and ≥ 3 comorbidities was associated with an increased risk of PTB (aOR 2.85-5.16). Fourteen out of thirty comorbidities were significantly associated with PTB (aOR 1.28-7.27), and the associations differed by sex and age. Network analysis identified three major clusters, mainly in the respiratory, circulatory, and endocrine/metabolic systems, in PTB cases.

CONCLUSIONS

Certain comorbidities involving multiple systems may significantly increase the risk of PTB. Enhanced awareness and surveillance of comorbidity are warranted to ensure early prevention and timely control of PTB.

The incidence of herpes zoster in China: A meta-analysis and evidence quality assessment

This review aimed to estimate the disease burden of herpes zoster (HZ) in China and explore the application of the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) approach in studies of disease burden. We searched for the literature of observational studies analyzing HZ incidence in populations of all ages in China. Meta-analysis models were constructed to calculate the pooled incidence of HZ and pooled risks of postherpetic neuralgia (PHN), HZ recurrence, and hospitalization. Subgroup analysis was performed according to gender, age, and quality assessment score. The quality of evidence for incidence was rated using the GRADE system. Twelve studies with a total of 25,928,408 participants were included in this review. The pooled incidence for all ages was 4.28/1000 person years (95% CI 1.22-7.35). It increased with the increasing in age especially for individuals aged ≥60 y, which was 11.69/1000 person years (95% CI 6.56-16.81). The pooled risks of PHN, recurrence, and hospitalization were 12.6% (95% CI 10.1-15.1), 9.7% (95% CI 3.2-16.2), and 6.0/100,000 population (95% CI 2.3-14.2), respectively. The quality of the evidence assessment of the pooled incidence by the GRADE for all ages was 'low'; however, it was 'moderate' for the ≥60 yold subgroup. HZ is a serious public health problem in China and is more significant in individuals older than 60 y. Therefore, an immunization strategy for the zoster vaccine should be considered. The evidence quality assessment by the GRADE approach indicated that we had more confidence in the estimation of aged population.

Trends and disparities in 44 national notifiable infectious diseases in China: An analysis of national surveillance data from 2010 to 2019

Research assessing the changing epidemiology of infectious diseases in China after the implementation of new healthcare reform in 2009 was scarce. We aimed to get the latest trends and disparities of national notifiable infectious diseases by age, sex, province, and season in China from 2010 to 2019. The number of incident cases and deaths, incidence rate, and mortality of 44 national notifiable infectious diseases by sex, age groups, and provincial regions from 2010 to 2019 were extracted from the China Information System for Disease Control and Prevention and official reports and divided into six kinds of infectious diseases by transmission routes and three classes (A-C) in this descriptive study. Estimated annual percentage changes (EAPCs) were calculated to quantify the temporal trends of incidence and mortality rate. We calculated the concentration index to measure economic-related inequality. Segmented interrupted time-series analysis was used to estimate the impact of the COVID-19 pandemic on the epidemic of notifiable infectious diseases. The trend of incidence rate on six kinds of infectious diseases by transmission routes was stable, while only mortality of sexual, blood-borne, and mother-to-child-borne infectious diseases increased from 0.6466 per 100 000 population in 2010 to 1.5499 per 100 000 population in 2019 by 8.76% per year (95% confidence interval [CI]: 6.88-10.68). There was a decreasing trend of incidence rate on Class-A infectious diseases (EAPC = -16.30%; 95% CI: -27.93 to -2.79) and Class-B infectious diseases (EAPC = -1.05%; 95% CI: -1.56 to -0.54), while an increasing trend on Class-C infectious diseases (EAPC = 6.22%; 95% CI: 2.13-10.48). For mortality, there was a decreasing trend on Class-C infectious diseases (EAPC = -14.76%; 95% CI: -23.46 to -5.07), and an increasing trend on Class-B infectious diseases (EAPC = 4.56%; 95% CI: 2.44-6.72). In 2019, the infectious diseases with the highest incidence rate and mortality were respiratory diseases (340.95 per 100 000 population), and sexual, blood-borne, and mother-to-child-borne infectious diseases (1.5459 per 100 000 population), respectively. The greatest increasing trend of incidence rate was observed in seasonal influenza, from 4.83 per 100 000 population in 2010 to 253.36 per 100 000 population in 2019 by 45.16% per year (95% CI: 29.81-62.33), especially among females and children aged 0-4 years old. The top disease with the highest mortality was still AIDs, which had the highest average yearly mortality in 24 provinces from 2010 to 2019, and its incidence rate (EAPC = 14.99%; 95% CI: 8.75-21.59) and mortality (EAPC = 9.65; 95%CI: 7.71-11.63) both increased from 2010 to 2019, especially among people aged 44-59 years old and 60 or older. Male incidence rate and mortality were higher than females each year from 2010 to 2018 on 29 and 10 infectious diseases, respectively. Additionally, sex differences in the incidence and mortality of AIDS were becoming larger. The curve lay above the equality line, with the negative value of the concentration index, which indicated that economic-related health disparities exist in the distribution of incidence rate and mortality of respiratory diseases (incidence rate: the concentration index = -0.063, p < 0.0001; mortality: the concentration index = -0.131, p < 0.001), sexual, blood-borne, and mother-to-child-borne infectious diseases (incidence rate: the concentration index = -0.039, p = 0.0192; mortality: the concentration index = -0.207, p < 0.0001), and the inequality disadvantageous to the poor (pro-rich). Respiratory diseases (Dec-Jan), intestinal diseases (May-Jul), zoonotic infectious diseases (Mar-Jul), and vector-borne infectious diseases (Sep-Oct) had distinct seasonal epidemic patterns. In addition, segmented interrupted time-series analyses showed that, after adjusting for potential seasonality, autocorrelation, GDP per capita, number of primary medical institutions, and other factors, there was no significant impact of COVID-19 epidemic on the monthly incidence rate of six kinds of infectious diseases by transmission routes from 2018 to 2020 (all p > 0.05). The incidence rates of six kinds of infectious diseases were stable in the past decade, and incidence rates of Class-A and Class-B infectious diseases were decreasing because of comprehensive prevention and control measures and a strengthened health system after the implementation of the new healthcare reform in China since 2009. However, age, gender, regional, and economic disparities were still observed. Concerted efforts are needed to reduce the impact of seasonal influenza (especially among children aged 0-4 years old) and the mortality of AIDs (especially among people aged 44-59 years old and 60 or older). More attention should be paid to the disparities in the burden of infectious diseases.