Serum biomarkers of inflammation and muscle strength among women with systemic lupus erythematosus

Muscle strength, not muscle mass, determines the health-related quality of life in Indonesian women with systemic lupus erythematosus

OBJECTIVE

No study evaluated the impact of low muscle strength and mass on the Sarcopenia-related Quality of Life (SarQoL) in women with SLE.

METHODS

This cross-sectional study recruited 145 women with SLE consecutively; muscle strength was measured with a calibrated Jamar handheld dynamometer, muscle mass was measured with appendicular muscle mass index (Tanita MC-780 MAP body impedance analyser) and health-related quality of life with SarQoL Questionnaire. The cut-off points for low muscle strength, low muscle mass and sarcopenia were derived from the Asian Working Group on Sarcopenia 2019. Statistical analysis was conducted with a t-test for mean difference, and logistic regression was used to evaluate for low muscle strength contributing factors.

RESULTS

There was a significant difference in the mean total score of SarQoL in individuals with normal compared with low muscle strength (74.36 vs 64.85; mean difference 9.50; 95% CI 2.10 to 5.33; p<0.001). On the other hand, there was no difference in individuals with normal compared with low muscle mass (71.07 vs 70.79; mean difference 0.28; -5.18 to 5.74; p=0.91). After minimally adjusted with age, we found moderate-severe joint pain (B -9.280; p<0.001) and low muscle strength (B -6.979; p=0.001) to be independently associated with low mean SarQoL total score.

CONCLUSION

There was a lower total SarQoL score in individuals with low muscle strength but not with low muscle mass.

Between-day reliability of cytokines and adipokines for application in research and practice

Purpose: This study assessed the biological reliability of peripheral human cytokines and adipokines, and the influence of participant characteristics on total error. This has essential application to interventional cytokine measurement to ensure that reported results are interpreted with confidence.

Methods: Participants (49% female, 18–85 years, n = 84) completed two consecutive-day testing sessions. Participants provided a venous blood sample at the same time of day across two consecutive days, under standardized participant presentation, including 24-h rested and 12-h fasted conditions. Multiplex immunoassay was used to assess inflammatory analytes from samples (predominantly plasma). Repeat measurements were conducted between-day for total precision quantification, and technical (technique) error was negated from the total to provide an estimate of biological (attributed to participant presentation) error.

Results: Whilst there was no evidence of statistically significant biological error, a small amount of biological error was consistently present across most analytes (∼3.3%/0.07 pg/ml), which was largest for measurement of leptin (7.3%/210 pg/ml). There was also an influence of sex on reliability of leptin and adiponectin (total model explained 6–7% of error variation), where females demonstrated the greatest error.

Conclusion: Biological error reported in this study should be applied to any future study or individual with a repeated measurement of cytokine concentrations over time that maintain best practice procedures (12-h fasted, 24-h rested). In most cases, raw error should be used, with exceptions for women for measurement of leptin and adiponectin. This approach will ensure that results are reported with certainty for improved reporting of intervention efficacy.

A prescription for exercise in systemic lupus erythematosus

Patients with systemic lupus erythematosus (SLE) have increased cardiovascular risk, and fatigue is a major subjective complaint. Sedentary lifestyle has been shown to have negative health impacts in cardiovascular and rheumatic disease, though exercise has not traditionally been incorporated into routine therapy recommendations. Regular exercise in SLE may improve difficult to treat Type 2 symptoms, such as fatigue, depression, stress, and quality of life. Insufficient counseling on exercise by physicians is a notable barrier for SLE patients to engage in physical activity. Aerobic exercise regimens are more commonly studied, and have been shown to improve cardiovascular health in SLE. Exercise may improve some inflammatory markers, though does not definitively affect SLE clinical disease activity. Physical activity should be recommended to improve quality of life and cardiovascular health in patients with SLE. Developing clearer guidelines for exercise regimens in a patient-centered manner is warranted, especially given diverse phenotypes of SLE patients and varying degrees of physical limitations.

The handgrip strength and risk of depressive symptoms: a meta-analysis of prospective cohort studies

PURPOSE

Many studies have investigated the association between handgrip strength (HGS) and depressive symptoms, but the conclusion remain controversial. We performed a meta-analysis to evaluate the longitudinal association between HGS and risk of depressive symptoms.

METHODS

PubMed, PSYCINFO and EMBASE databases were searched for eligible publications up to April 2020. Pooled relative risks (RRs) with 95% confidence intervals were calculated using random-effects model. Publication bias was estimated using Egger's test and the funnel plot. Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of eligible studies.

RESULTS

The present meta-analysis included 8 cohort studies with 30,727 participants. Overall, higher HGS was related to a decreased risk of depressive symptoms: the pooled risk ratio (RR) of 0.74 [95% confidence intervals (CI) 0.65-0.85] with a moderate heterogeneity (I² = 60.5%, P = 0.013). HGS was significantly associated with a reduced risk of depressive symptoms in males (RR = 0.69; 95% CI 0.50-0.94), but not in females.

CONCLUSIONS

Lower HGS was associated with an increased risk of depressive symptoms. Further studies are needed to confirm these findings and to investigate the sex differences.

Relationships Between Eating Behaviors and Hand Grip Strength Among Chinese Adults: A Population-Based Cross-Sectional Study

Purpose

Poor eating behaviors are associated with imbalances in energy and food intake, which may directly or indirectly contribute to muscle strength loss. This study aimed to investigate the association between eating behaviors and hand grip strength in Chinese adults.

Materials and Methods

We designed and conducted a cross-sectional study of 2009 Chinese individuals aged 25–65 years in 2017. Eating behaviors, including breakfast consumption, snacking after dinner, and eating rate, were assessed using a self-administered questionnaire. Hand grip strength was assessed using a digital grip dynamometer. Age, sex, BMI, physical activity, educational level, occupation, living status, sleep duration, smoking and drinking status, hypertension, diabetes, and depressive symptoms were used as confounding factors.

Results

After final adjustments for confounding factors, grip strength was measured as 35.2 (95% confidence interval [CI]: 34.7–35.8), 36.0 (95% CI: 35.6–36.4), and 36.9 (95% CI: 36.6–37.3) for those who skipped, occasionally ate, and regularly ate breakfast, respectively (p for trend <0.001). Those who always, sometimes, and seldom snacked after dinner (p for trend <0.001) reported the following grip strength: 34.7 (95% CI: 34.0–35.3), 36.2 (95% CI: 35.8–36.6), and 36.9 (95% CI: 36.6–37.2), respectively. Significant associations were not found between eating rate and grip strength.

Conclusion

This study showed that higher frequency of breakfast consumption and lower frequency of snacking after dinner were associated with higher grip strength in Chinese adults. Therefore, eating behaviors may be involved in muscle function.

Higher handgrip strength predicts a lower risk of depressive symptoms in rural Chinese populations

BACKGROUND

The longitudinal associations between handgrip strength (HGS) and depressive symptoms remain unclear, especially in developing countries. The aim of this cohort study was to explore the associations between HGS and the incidence of depressive symptoms in China.

METHODS

This prospective cohort study enrolled 8470 participants living in 450 urban communities and rural villages within 28 provinces of China. Depressive symptoms were assessed using the 10-item Center for Epidemiological Studies Depression Scale. Cox proportional hazards regression models were used to examine the associations between baseline HGS and the incidence of depressive symptoms.

RESULTS

During the following period (mean follow-up, 3.75 years; 95% confidence interval [CI], 3.73-3.76 years), 2,027 (23.93%) out of 8470 participants developed depressive symptoms. The risk of depressive symptoms decreased progressively with both increasing weighted HGS (P for trend = 0.04) and absolute HGS (P for trend < 0.001) after multivariate-adjustments. Compared with participants in the lowest quartiles of weighted and absolute HGS, the multivariate-adjusted hazard ratios (HRs) (95% CIs) of depressive symptoms for participants in the highest quartiles were 0.83 (0.71, 0.98) and 0.74 (0.62, 0.89), respectively. The interaction terms of weighted HGS-place of residence (P for interaction < 0.001) and absolute HGS-place of residence (P for interaction = 0.03) were both significant. Higher weighted and absolute HGS were associated with a lower incidence of depressive symptoms for participants living in rural villages but not urban communities.

CONCLUSIONS

The results suggest that HGS predicts a lower risk of depressive symptoms in Chinese rural populations.

Detrimental association between quadriceps strength and exposure to polycyclic aromatic hydrocarbons in elderly adults

Polycyclic aromatic hydrocarbons (PAHs) are environmental pollutants primarily from the incomplete combustion of organic materials. Myriads of studies have reported the associations between PAH exposure with several adverse health outcomes. However, no previous study had explored the relationship between PAH exposure with muscle strength in the elderly population. In the present study, we included 473 elderly adults who were obtained from the US National Health and Nutrition Examination Survey (NHANES) (2001-2006). PAH metabolites were measured in urine samples. Muscle strength was determined as the isokinetic strength of the quadriceps. Pertinent variables were analyzed by various standard measurements. The association between PAH exposure and muscle strength was examined using multivariable linear regression models. After fully adjusting for covariables, PAH metabolites had a negative relationship with muscle strength, especially 3-fluorene (β = -0.021, 95% CI: -0.042, 0.000) and 2-fluorene (β = -0.020, 95% CI: -0.034, -0.005). Notably, the relationship remained significant in males, but not in females. PAH exposure is associated with decreased muscle strength in the US elderly population. Further studies are needed to bring to light the underlying mechanisms for these findings. In addition, it is important to provide interventions and determine strategies for treating the adverse impact of PAH exposure on dynapenia. Novelty PAH exposure is associated with decreased muscle strength in elderly adults. The adverse impact remains in males.

Increased flexibility, pain reduction and unaltered levels of IL-10 and CD11b + lymphocytes in patients with systemic lupus erythematosus were associated with kinesiotherapy

The effect of physical activity on the immune system is still poorly understood in cases of systemic lupus erythematosus (SLE). Therefore, our aim was to investigate differences in the serum levels of cytokines (IL-2, IL-5, IL-6, IL-8, IL-10 and TNF-α) and the numbers of CD11b + and CXCR2 + neutrophils and lymphocytes in women with SLE undergoing drug treatment, without ( n = 9) or with ( n = 5) 4 months of kinesiotherapy. Parameters related to functional capacity were also analyzed. In the case of the patients who were not submitted to kinesiotherapy, there were reductions in the levels of IL-5, IL-6 and IL-10, and an increase in the number of CD11b + leukocytes, in addition to an increase in abdominal circumference after the monitoring time. Patients submitted to kinesiotherapy did not present changes in serum cytokines or in the numbers of CD11b + and CXCR2 + neutrophils and lymphocytes, but there were increases of flexibility and strength, as well as a reduction in pain sensation after the monitoring time. In conclusion, kinesiotherapy was able to increase flexibility and reduce pain in SLE patients without influencing immune parameters.