Bidirectional causal relationship between depression and frailty: a univariate and multivariate Mendelian randomisation study.

BACKGROUND: cumulative evidence from cohort studies suggested that there were inconsistent conclusions as to whether there was a bidirectional association between depression and frailty. Therefore, this study used a bidirectional two-sample Mendelian randomisation (MR) study to investigate the causal relationship between depression and frailty. METHODS: we performed univariate and multivariate bidirectional MR analyses to assess the causal association between depression and frailty. Independent genetic variants associated with depression and frailty were selected as instrumental variables. Inverse variance weighted (IVW), MR-Egger, weighted median and weighted mode were mainly used in univariate MR analysis. Multivariate MR (MVMR) analyses used multivariable inverse variance-weighted methods to individually and jointly adjust for three potential confounders, body mass index (BMI), age at menarche (AAM) and waist-to-hip ratio (WHR, adjusted for BMI). RESULTS: univariate MR analysis showed a positive causal relationship between depression and risk of frailty (IVW, odds ratio (OR) = 1.30, 95% confidence interval (CI) = 1.23-1.37, P = 6.54E-22). Causal relationship between frailty and risk of depression (IVW, OR = 1.69, 95% CI = 1.33-2.16, P = 2.09E-05). MVMR analysis revealed that the bidirectional causal association between depression and frailty remained after adjusting for three potential confounders, BMI, AAM and WHR (adjusted for BMI), individually and in combination. CONCLUSIONS: our findings supported a causal relationship between genetically predicted depression and frailty in both directions.

The prevalence and influencing factors of frailty in patients with chronic kidney disease: a systematic review and meta-analysis.

BACKGROUND: To investigate the prevalence and influencing factors of frailty and pre-frailty in chronic kidney disease (CKD) patients and thereby provide a scientific basis for effective avoidance of frailty in patients with CKD. METHODS: PubMed, EMBASE, Web of Science, EBSCO, Cochrane Library, CNKI, VIP, CBMdisc, and Wanfang databases were searched for relevant studies published till December 31, 2021. The summary results were described as odds ratios (ORs) or standardized mean differences (SMDs) with 95% confidence intervals (CIs). A meta-analysis was performed using StataSE12.0. RESULTS: Fifteen published studies, which enrolled a total of 3294 CKD patients, met the inclusion criteria. The combined prevalence of frailty in CKD patients was 38.1% (95% CI 29.7-46.5%) and pre-frailty was 37.9% (95% CI 32.7-43.1%). The main factors influencing frailty in CKD patients were age (SMD 0.524, 95% CI 0.326-0.723), diastolic blood pressure (SMD - 0.294, 95% CI - 0.518 to - 0.071), body mass index (BMI) (SMD - 0.267, 95% CI - 0.471 to - 0.064), grip strength (SMD - 0.929, 95% CI - 1.233 to - 0.626), hemoglobin level (SMD - 0.346, 95% CI - 0.448 to - 0.243), serum albumin level (SMD - 0.533, 95% CI - 0.655 to - 0.411), Charlson Comorbidity Index (SMD 0.421, 95% CI 0.150-0.692), multiple medications (SMD 0.625, 95% CI 0.354-0.895), Mini-Mental State Examination (MMSE) score (SMD - 0.563, 95% CI - 0.846 to - 0.280), and female (OR 2.391, 95% CI 1.236-4.627). CONCLUSION: Frailty is common in CKD patients. The prevalence of frailty among CKD patients was related to age, diastolic blood pressure, BMI, grip strength, hemoglobin and serum albumin levels, Charlson Comorbidity Index, multiple medications, MMSE score, and female.