The role of education in the association between self-rated health and levels of C-reactive protein: a cross-sectional study in rural areas of China

Objectives This study aims to examine the association between self-rated health (SRH) and levels of C-reactive protein (CRP) among adults aged 45 to 101 years old in rural areas of China, and to explore the role of education in the association. Design Cross-sectional study. Setting The study population was derived from two databases in China: Nanping project (NP) and the China Health and Retirement Longitudinal Study (CHARLS). Participants There were 646 participants from a rural area of Nanping (NP) and 8555 rural participants from a national representative sample of China (CHARLS). Methods CRP was measured using a high sensitivity sandwich enzyme immunoassay in the NP and immunoturbidimetric assay in the CHARLS. SRH was assessed by SRH questionnaires and categorised into good and poor. Education was measured by the maximum years of schooling and dichotomised into illiterate and literate. Multivariate linear regression models were used to study the associations. Results Compared to people with good SRH, those with poor SRH had higher levels of CRP in NP (β=0.16, 95% CI -0.02 to 0.34) and in CHARLS (β=0.07, 95% CI 0.02 to 0.11) after adjusting for potential confounders. Similar findings were observed in the pooled population (β=0.08, 95% CI 0.03 to 0.12), especially in men (β=0.13, 95% CI 0.06 to 0.20) and in literate people (β=0.12, 95% CI 0.06 to 0.18). Conclusion Poor SRH may be a predicator of elevated levels of CRP among middle-aged and older people in rural areas, especially in men and literate people

The role of education in the association between self-rated health and levels of C-reactive protein: a cross-sectional study in rural areas of China

ObjectivesThis study aims to examine the association between self-rated health (SRH) and levels of C-reactive protein (CRP) among adults aged 45 to 101 years old in rural areas of China, and to explore the role of education in the association.DesignCross-sectional study.SettingThe study population was derived from two databases in China: Nanping project (NP) and the China Health and Retirement Longitudinal Study (CHARLS).ParticipantsThere were 646 participants from a rural area of Nanping (NP) and 8555 rural participants from a national representative sample of China (CHARLS).MethodsCRP was measured using a high sensitivity sandwich enzyme immunoassay in the NP and immunoturbidimetric assay in the CHARLS. SRH was assessed by SRH questionnaires and categorised into good and poor. Education was measured by the maximum years of schooling and dichotomised into illiterate and literate. Multivariate linear regression models were used to study the associations.ResultsCompared to people with good SRH, those with poor SRH had higher levels of CRP in NP (β=0.16, 95% CI −0.02 to 0.34) and in CHARLS (β=0.07, 95% CI 0.02 to 0.11) after adjusting for potential confounders. Similar findings were observed in the pooled population (β=0.08, 95% CI 0.03 to 0.12), especially in men (β=0.13, 95% CI 0.06 to 0.20) and in literate people (β=0.12, 95% CI 0.06 to 0.18).ConclusionPoor SRH may be a predicator of elevated levels of CRP among middle-aged and older people in rural areas, especially in men and literate people.</jats:sec

Association between intergenerational contact and cognitive function in middle-aged and older Chinese adults: The mediating role of functional disability and depressive symptoms

Abstract Background Previous studies have documented the impact of intergenerational contact on cognitive function in Chinese adults, however, few have focused on the possible mediating pathways. This study aimed to test a hypothetical model in which functional disability and depressive symptoms mediate the association between intergenerational contact and cognitive function. Methods This longitudinal study included data of 3666 participants aged 45 years or older (mean age: 60.2 years) from the China Health and Retirement Longitudinal Study (CHARLS) from 2011 to 2015. Intergenerational contact was measured as the frequency of contact with children and categorized as frequent (≥ 1 time/week) or infrequent (< 1 time/week). Cognitive function was measured in two dimensions: episodic memory and executive function. Depressive symptoms and functional disability were assessed as continuous variables using the 10-item Center for Epidemiological Studies Depression Scale, Activities of Daily Living, and Instrumental Activities of Daily Living Scales. The mediating pathways were quantified using the SPSS PROCESS macro. Results Frequent intergenerational contact correlated with a better cognitive function (coefficient: 0.73, 95%CI: 0.39 to 1.06), with plausible mediated pathways via functional disability without depressive symptoms (coefficient: 0.03, 95%CI: 0 to 0.06, proportion mediated: 4.11%), depressive symptoms without functional disability (coefficient: 0.04, 95%CI: 0.01 to 0.08, proportion mediated: 5.48%), and functional disability and depressive symptoms in a chain (coefficient: 0.01, 95%CI: 0 to 0.02, proportion mediated: 1.37%). Conclusion Functional disability and depressive symptoms may partly explain the association between intergenerational contact and cognitive function. Further research is needed to explore the mechanisms underlying the association between intergenerational contact and cognitive function

Sex-related differences in the hypertriglyceridemic-waist phenotype in association with hyperuricemia: a longitudinal cohort study

Abstract Background There is limited longitudinal evidence supporting the association between the hypertriglyceridemic-waist (HTGW) phenotype and hyperuricemia. This study aimed to examine the longitudinal relationship between hyperuricemia and the HTGW phenotype among males and females. Methods A total of 5562 hyperuricemia-free participants aged 45 or over from the China Health and Retirement Longitudinal Study (mean age: 59.0) were followed for 4 years. The HTGW phenotype was defined as having elevated triglyceride levels and enlarged waist circumference (cutoffs for males: 2.0 mmol/L and 90 cm; females: 1.5 mmol/L and 85 cm). Hyperuricemia was determined by uric acid cutoffs (males: 7 mg/dl; females: 6 mg/dl. Multivariate logistic regression models were used to assess the association between the HTGW phenotype and hyperuricemia. The joint effect of the HTGW phenotype and sex on hyperuricemia was quantified, and the multiplicative interaction was assessed. Results During the four-year follow-up, 549 (9.9%) incident hyperuricemia cases were ascertained. Compared with those with normal levels of triglycerides and waist circumference, participants with the HTGW phenotype had the highest risk of hyperuricemia (OR: 2.67; 95% CI: 1.95 to 3.66), followed by an OR of 1.96 (95% CI: 1.40 to 2.74) for only higher triglyceride levels and 1.39 (95% CI: 1.03 to 1.86) for only greater waist circumference. The association between HTGW and hyperuricemia was more prominent among females (OR = 2.36; 95% CI: 1.77 to 3.15) than males (OR = 1.29; 95% CI: 0.82 to 2.04), with evidence of a multiplicative interaction (P = 0.006). Conclusions Middle-aged and older females with the HTGW phenotype may at the highest risk of hyperuricemia. Future hyperuricemia prevention interventions should be primarily targeted for females with the HTGW phenotype. </jats:sec

The association between healthy aging index and trajectories of disability : a population-based cohort study

Background Healthy aging index (HAI) could predict adverse health consequences including mortality and disability independent of age and comorbidity. We investigated the role of HAI on trajectories of disability throughout later life based on a nationally representative sample.Methods We examined 1733 participants aged over 60 years from the China Health and Retirement Longitudinal Study (CHARLS) followed for 7 years/4 waves repeatedly. Systolic blood pressure [SBP], cognitive function, cystatin C, peak expiratory flow [PEF], and fasting glucose were categorized using tertile or clinical reference range, and scored as 0 (healthiest), 1 (less healthy) and 2 (least healthy) respectively to further generate HAI summary scores (range 0–10). Disability was defined as the sum of impaired activities of daily living (ADL) and instrumental activities of daily living (IADL). We used linear mixed-effects model to study the association between HAI and trajectories of disability.Results A total of 10.5% of participants represented in the healthiest group and 22.5% ended up as the least healthy. After adjusting for all potential confounders, disability progression was significantly faster (β = 0.27, 95% CI 0.11–0.42) in the least healthy group when comparing with the healthiest.Conclusion Our findings suggest that HAI is associated with disability progression among adults aged over 60 years old. It might be beneficial for future interventions to specifically target older adults with high HAI scores as a means of reducing disability.</p