The effect of COVID-19 infection on patients with rheumatic diseases in China.

OBJECTIVES: At the end of 2022, the COVID-19 outbreak erupted in China, and BA.5.2 or BF.7 subtypes of Omicron novel variations were implicated in more than 90% of the cases. We created a real-world questionnaire survey to better understand how this new variant pandemic was affecting rheumatic patients in China. METHODS: During the COVID-19 outbreak in China, the subjects of this study were rheumatic patients and non-rheumatic individuals (control group), who were matched for sex and age. Professional physicians carefully questioned the participants before administering a questionnaire as part of the study. This study focused on the general baseline characteristics, clinical symptoms and treatment after COVID-19 infection, and the target populations' awareness of COVID-19. RESULTS: The study included 1130 participants, of whom 572 were assigned to the rheumatic group and 558 to the control group. The percentage of vaccinated controls was significantly higher than that of rheumatic patients (90.1% vs. 62.8%, p < 0.001), while the rate of COVID-19 infection was not significantly different between the two groups (82.3% vs. 86.6%, p = 0.051). Patients with rheumatic disease experienced substantially more days of fever following infection (2.87 ± 3.42 vs. 2.18 ± 1.65, p = 0.002) compared to individuals in the control group. The rheumatic patients had a greater prevalence of cough (67.1% vs. 54.0%, p < 0.001), somnipathy (13.8% vs. 6.0%, p < 0.001), and conjunctivitis/ophthalmodynia (5.3% vs. 2.1%, p = 0.008), while dry throat/throat pain/weakness (49.9% vs. 59.4%, p = 0.003), myalgia/osteodynia (33.3% vs. 41.8%, p = 0.003), and dyspnea (14.0% vs. 25.3%, p < 0.001) were more likely to occur in non-rheumatic group after infection. Human immunoglobulin (2.1% vs. 0.2%, p = 0.006), glucocorticoids (19.5% vs. 1.6%, p < 0.001), oxygen support (6.8% vs. 2.1%, p < 0.001), and traditional Chinese medicine (21.9% vs. 16.6%, p = 0.037) were all more frequently used by rheumatic patients with COVID-19 infection. People in the control group were more confused about whether to use masks in following social activities after contracting COVID-19 (14.7% vs. 7.6%, p = 0.001). In the control group, more individuals than patients with rheumatic disease (25.1% vs. 13.4%, p < 0.001) expressed an interest to receive the vaccine again. After being exposed to COVID-19, the majority of rheumatic patients (66.9%) reported no discernible change, only 29.1% reported a worsening of their symptoms, and the remaining 4% indicated an improvement. CONCLUSIONS: After the COVID-19 outbreak in China, the proportion of patients with rheumatic diseases infected with the virus was similar to that of normal individuals. But the clinical symptoms, follow-up treatment requirements, and awareness of the COVID-19 among rheumatic patients were distinct from those among non-rheumatic patients, necessitating the use of individualized diagnosis and treatment plans as well as health advice by medical professionals in clinical work. Key Points • Despite there were different comorbidities and vaccination rates, the rate of COVID-19 infection in patients with rheumatic disease was similar to that of normal individuals. • After COVID-19 infection, rheumatic patients and normal controls had different clinical symptoms and drug usage. • After being exposed to COVID-19, the majority of rheumatic patients felt no significant change in the primary disease, while the normal controls was more likely to accept a new vaccine injection and confused about whether to use masks in following social activities.

Anti-hyperuricemic and nephroprotective effects of rhein in hyperuricemic mice.

Hyperuricemia has been considered to be a key risk factor for kidney disease. The formation of uric acid crystals in the kidney further stimulates an intensive inflammatory response. Rhein possesses various pharmacological activities, including anti-inflammatory, antioxidative, antitumor, purgative effects, and so on. To our knowledge, no previous work has been reported about the therapeutic effect of rhein on urate nephropathy. In this study, a model of hyperuricemia and nephropathy induced by adenine and ethambutol in mice was established. Meanwhile, the potential beneficial effects and mechanisms of rhein on hyperuricemia and nephropathy were also investigated. The results demonstrated that rhein significantly decreased the serum uric acid level by inhibiting the xanthine oxidase activity and increasing the excretion of urinary uric acid. In addition, rhein also markedly improved kidney damage related to hyperuricemia. Further investigation indicated that rhein improved the symptoms of nephropathy through decreasing the production of proinflammatory cytokines, including interleukin 1ß, prostaglandin E2, and tumor necrosis factor-α and inhibiting the expression of transforming growth factor-ß1. The present study suggests that rhein may have a considerable potential for development as an anti-hyperuricemic and nephroprotective agent for clinical application.

Study on the anti-gout activity of chlorogenic acid: improvement on hyperuricemia and gouty inflammation.

Gout is a metabolic disorder associated with hyperuricemia resulting in the deposition of monosodium urate (MSU) crystals in joints and tissues. Lowering serum uric acid (Sur) levels and anti-inflammation are highly essential in treating gout. Chlorogenic acid (CA), as one of the most abundant polyphenols in the Chinese medicines, has been rarely reported to have an anti-gout effect. The model of potassium oxonate (PO)-induced hyperuricemia in mice and MSU crystal-induced inflammation in rats has been established in this study. The potential beneficial effects and mechanisms of CA on hyperuricemia and gouty arthritis were elucidated. The results demonstrated that CA significantly decreased the Sur level by inhibiting the xanthine oxidase (XOD) activity but not increasing the urinary uric acid (Uur) level. In addition, CA also exhibited the effect of suppressing paw swelling. Further investigation indicated that CA improved the symptoms of inflammation induced by MSU crystals by inhibiting the production of proinflammatory cytokines including interleukin-1ß (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α). The present study suggests that CA may have a considerable potential for development as an anti-gouty arthritis agent for clinical application.