Background: We aim to investigate the profile of acute antibody response in COVID-19 patients, and provide proposals for the usage of antibody test in clinical practice. Methods: A multi-center cross-section study (285 patients) and a single-center follow-up study (63 patients) were performed to investigate the feature of acute antibody response to SARS-CoV-2. A cohort of 52 COVID-19 suspects and 64 close contacts were enrolled to evaluate the potentiality of the antibody test. Results: The positive rate for IgG reached 100% around 20 days after symptoms onset. The median day of seroconversion for both lgG and IgM was 13 days after symptoms onset. Seroconversion of IgM occurred at the same time, or earlier, or later than that of IgG. IgG levels in 100% patients (19/19) entered a platform within 6 days after seroconversion. The criteria of ‘IgG seroconversion’ and ‘> 4-fold increase in the IgG titers in sequential samples’ together diagnosed 82.9% (34/41) of the patients. Antibody test aided to confirm 4 patients with COVID-19 from 52 suspects who failed to be confirmed by RT-PCR and 7 patients from 148 close contacts with negative RT-PCR. Conclusion: IgM and IgG should be detected simultaneously at the early phase of infection. The serological diagnosis criterion of seroconversion or the ‘>; 4-fold increase in the IgG titer’ is suitable for a majority of COVID-19 patients. Serologic test is helpful for the diagnosis of SARS-CoV-2 infection in suspects and close contacts.

Purpose: Hypertension is a major risk factor for cardiovascular diseases and stroke, and it requires lifelong medication. This study aimed to investigate the factors impacting on Health-Related Quality of Life (HRQoL) among hypertensive patients in Chongqing, China, and to provide evidence-based strategies to improve their HRQoL. Methods: This cross-sectional survey was conducted in Chongqing, China. Of 600 randomly selected patients, 586 patients agreed to participate and 567 patients completed the survey. A SF-36 (Medical Outcomes Study (MOS) Short Form Health Survey questionnaire) that included eight domains: physical functioning, role limitations due to physical problems, body pain, general health, vitality, social function, role limitations due to emotional problems, and mental health was used to measure HRQoL. Linear regressions were used; each domain of HRQoL was measured in the stratification of sex. Results: Self-perceived relatively low economic burden caused by hypertension and regular physical activity had a positive impact on HRQoL (p < 0.05) for both men and women. For women, younger age was associated with higher scores of measuring physical functioning and body pain. Living with more than three family members had a positive impact on domains, including physical functioning. Emotional self-regulation had a positive association with women’s mental health. Alcohol use for men was associated with higher scores in physical and mental health measures, and emotional self-regulation showed some positive impact on general health. Conclusion: Perceived economic burden caused by hypertension was the most common factor impacting on patients’ HRQoL. Female patients were more susceptible when compared to male patients. Health intervention strategies need to be further explored and adapted to the context of improving HRQoL for patients who suffer from hypertension and other chronic non-communicable diseases.

Little is known about the association between spicy food intake, dietary approaches to stop hypertension (DASH) score, and incident stroke. This study aimed to explore the association of eating spicy food, DASH score, and their interaction with stroke incidence. We included 22,160 Han residents aged 30–79 in southwest China from the China Multi-Ethnic Cohort. Three hundred and twelve cases were newly diagnosed with stroke by October 8, 2022, during a mean of 45.5 months of follow-up. Cox regression analyses showed that eating spicy food reduced stroke risk by 34% among people with low DASH scores (HR 0.66, 95%CI 0.45–0.97), while individuals with high DASH scores versus low DASH scores had a 46% lower stroke incidence among spicy food nonconsumers (HR 0.54, 95%CI 0.36–0.82). The HR of the multiplicative interactive term was 2.02 (95%CI 1.24–3.30) and the overall estimates of relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP), and the synergy index (S) were 0.54 (95%CI 0.24–0.83), 0.68 (95%CI 0.23–1.14), and 0.29 (95%CI 0.12–0.70), respectively. Consuming spicy food seems to be associated with lower stroke risk only in people who have a lower DASH score, while the beneficial effect of higher DASH scores seems to be found only among nonconsumers of spicy food, and a negative interaction may exist between them in southwestern Chinese aged 30–79. This study could provide scientific evidence for dietary guidance to reduce stroke risk.

Objectives Since 2009, China has introduced policies, principally targeting health professionals, to reduce caesarean section (CS) overuse. In 2016, China endorsed a universal two-child policy. Advanced maternal age and previous CS may indicate changes in obstetric risks, which raise concerns on the need for and safety of CS. This study investigated changes in CS rates in 2008–2018, and factors associated with CS use during the period of transition from the one-child to two-child policy era. Design We used births data from the cross-sectional National Household Health Services Surveys in 2013 and 2018. Setting Population-based national survey. Participants Women who had the last live birth within 5 years before the survey. Primary outcome measure CS rate. Results Overall CS use increased from 40.9% in 2008 to 47.2% in 2014 with significant increase in rural areas and the western region, and slightly decreased to 45.2% in 2018 with the greatest decrease among nulliparous women. Maternal request for CS by urban nulliparous women decreased from 36.8% in 2008–2009 to 22.2% in 2016–2018, but this change was not statistically significant in rural areas. Maternal age over 35 years old (OR 2.40, 95% CI 1.72 to 3.35) and births that occurred at a private hospital (OR 1.52, 95% CI 1.25 to 1.86) were associated with CS use among nulliparous women in 2016–2018. The CS rate among multiparous women increased over time. Individual socioeconomic factors associated with CS use among multiparous women. Conclusions The CS rate rise in China in 2008–2018 is attributable to increased use in rural areas and the less developed western region. The population policy shift, alongside facility policies for unnecessary CS reduction, are likely factors in CS reduction in urban areas. The challenge remains to reduce unnecessary CS, at the same time as providing safe, universal access to CS for women in need.

Hyperuricemia is associated with substantial health and economic burden all over the world. Dietary habits are an important influencing factor of hyperuricemia. This study aimed to investigate the relationship between spicy food intake and hyperuricemia based on a large population. A total of 22,125 individuals aged 30–79 were enrolled in China Multi-Ethnic Cohort (CMEC), Chongqing region. Spicy food intake information was collected by a standardized questionnaire. The association between spicy food intake and hyperuricemia was estimated by multivariable logistic regression models and multiple linear regression models. Additionally, we explored these relations in subgroups stratified by sex and age. Furthermore, sensitivity analyses were conducted to verify the stability of current findings. After controlling for potential confounders, compared with participants who never consumed spicy food and consumed less hot, participants who ate 3–5 days per week and very hot had the highest risk of hyperuricemia; the ORs (95% CIs) were 1.28 (1.09, 1.5) and 1.22 (0.92, 1.63), respectively. Additionally, the corresponding ORs (95% CIs) for each level increment in the frequency and degree of pungency in spicy food intake were 1.04 (1.01, 1.07) (P trend = 0.009) and 1.15 (1.04, 1.26) (P trend = 0.004). Further in sex-stratified and age-stratified analysis, similar positive associations were observed among men and those aged 30–59, but no significant association was found among women and those aged 60–79. In the linear regression models, 3–5 days per week and moderate pungency in spicy food intake were associated with 5.21 μmol/L (95% CI: 1.72, 8.70) and 4.69 μmol/L (95% CI: 1.93, 7.45) higher serum urate level. Results in further subgroup analysis were generally consistent with the logistic regression models. This study suggests that spicy food intake may be a risk factor for hyperuricemia, especially in men and younger people, and more studies are warranted to verify the causal associations.