Social support and frailty progression in community-dwelling older adults.

Objectives: Despite the growing evidence regarding the influence of social factors on frailty in older adults, the effect of social support remains unclear. This study aims to assess the association between social support and frailty progression (transition and incidence) in a sample of community-dwelling older adults. Methods: Using a cohort study design, 1,059 older adults from the Berlin Initiative Study were followed up for 2.1 years. Multinomial and logistic regression analyses were performed to assess the association of social support using Oslo Social Support Scale-3 with frailty transition and incidence, respectively. Gender differences were explored using stratified analyses. Results: At baseline, frailty prevalence in the study population [mean (SD) age 84.3 (5.6) years; 55.8% women] reached 33.1% with 47.0, 29.4 and 23.6% of the participants reporting moderate, strong and poor social support, respectively. Over the follow-up period, social support was not significantly associated with the frailty transition categories in the adjusted model. Conversely, the adjusted logistic regression analysis showed that participants with poor social support had twice the odds of becoming frail compared to those with strong social support (OR 2.07; 95% CI 1.08-3.95). Gender-stratified analyses showed comparable estimates to the main analysis but were statistically non-significant. Discussion: Our study results underpin the role of social factors in frailty incidence and highlight social support as a potential target for frailty-preventing interventions in older adults. Therefore, it is important to adopt a biopsychosocial model rather than a purely biomedical model to understand and holistically improve the health of community-dwelling older adults.

Effect modification of polypharmacy on incident frailty by chronic kidney disease in older adults.

BACKGROUND: Frailty and polypharmacy are common conditions in older adults, especially in those with chronic kidney disease (CKD). Therefore, we analyzed the association of polypharmacy and incident frailty and the effect modification by CKD in very old adults. METHODS: In non-frail individuals within the Berlin Initiative (cohort) Study, polypharmacy (≥ 5 medications) was assessed according to multiple definitions based on the number of regular and on demand prescription and over the counter drugs, as well as vitamins and supplements. CKD was defined as an estimated glomerular filtration rate < 60 mL/min/1.73m2 and/or an albumin-creatinine ratio ≥ 30 mg/g. Incident frailty was assessed at follow-up using Fried criteria. Logistic regression was applied to assess (1) the association of different polypharmacy definitions with incident frailty and (2) effect modification by CKD. RESULTS: In this cohort study, out of 757 non-frail participants (mean age 82.9 years, 52% female, 74% CKD), 298 (39%) participants reported polypharmacy. Over the observation period of 2.1 years, 105 became frail. Individuals with polypharmacy had 1.96 adjusted odds (95% confidence interval (CI): 1.20-3.19) of becoming frail compared to participants without polypharmacy. The effect of polypharmacy on incident frailty was modified by CKD on the additive scale (relative excess risk due to interaction: 1.56; 95% CI 0.01-3.12). CONCLUSIONS: This study demonstrates an association of polypharmacy and incident frailty and suggests strong evidence for an effect modification of CKD on polypharmacy and incident frailty. Revision of prescriptions could be a target strategy to prevent frailty occurrence, especially in older adults with CKD.

Diagnostic Validity of Chronic Kidney Disease in Health Claims Data Over Time: Results from a Cohort of Community-Dwelling Older Adults in Germany.

Purpose: The validity of ICD-10 diagnostic codes for chronic kidney disease (CKD) in health claims data has not been sufficiently studied in the general population and over time. Patients and Methods: We used data from the Berlin Initiative Study (BIS), a prospective longitudinal cohort of community-dwelling individuals aged ≥70 years in Berlin, Germany. With estimated glomerular filtration rate (eGFR) as reference, we assessed the diagnostic validity (sensitivity, specificity, positive [PPV], and negative predictive values [NPV]) of different claims-based ICD-10 codes for CKD stages G3-5 (eGFR <60mL/min/1.73m²: ICD-10 N18.x-N19), G3 (eGFR 30-<60mL/min/1.73m²: N18.3), and G4-5 (eGFR <30mL/min/1.73m²: N18.4-5). We analysed trends over five study visits (2009-2019). Results: We included data of 2068 participants at baseline (2009-2011) and 870 at follow-up 4 (2018-2019), of whom 784 (38.9%) and 440 (50.6%) had CKD G3-5, respectively. At baseline, sensitivity for CKD in claims data ranged from 0.25 (95%-confidence interval [CI] 0.22-0.28) to 0.51 (95%-CI 0.48-0.55) for G3-5, depending on the included ICD-10 codes, 0.20 (95%-CI 0.18-0.24) for G3, and 0.36 (95%-CI 0.25-0.49) for G4-5. Over the course of 10 years, sensitivity increased by 0.17 to 0.29 in all groups. Specificity, PPVs, and NPVs remained mostly stable over time and ranged from 0.82-0.99, 0.47-0.89, and 0.66-0.98 across all study visits, respectively. Conclusion: German claims data showed overall agreeable performance in identifying older adults with CKD, while differentiation between stages was limited. Our results suggest increasing sensitivity over time possibly attributable to improved CKD diagnosis and awareness.

The Lack of a Standardized Definition of Chronic Dialysis Treatment in German Statutory Health Insurance Claims Data.

BACKGROUND: Chronic kidney failure (CKF) is often treated with dialysis, which is invasive and costly and carries major medical risks. The existing studies of patients with CKF requiring dialysis that are based on claims data from German statutory health insurance (SHI) carriers employ varying definitions of this entity, with unclear consequences for the resulting statistical estimates. METHODS: We carried out a cohort study on four random samples, each consisting of 62 200 persons aged 70 or above, from among the insurees of the SHI AOK Nordost, with one sample for each of the years 2012, 2014, 2016, and 2018. The prevalence, incidence, mortality, and direct health care costs of CKF requiring dialysis were estimated and compared on the basis of four different definitions from literature and a new definition developed by the authors in reference to billing data. RESULTS: The different definitions led to variation in 12-month prevalences (range: 0.33-0.61%) and 6-month incidences (0.058-0.100%). The percentage of patients with prior acute kidney injury (AKI) ranged from 27.6% to 61.8%. Among incident patients, three-month survival ranged from 70.2% to 88.1%, and six-month survival from 60.5% to 81.3%. In CKF patients without prior AKI, the survival curves differed less across definitions (80.2-91.8% at three months, 70.7-84.4% at six months). The monthly health care costs ranged from €6010 to €9606, with marked variability across definitions in the costs of inpatient and outpatient care. CONCLUSION: The lack of a standardized definition of CKF requiring dialysis in German SHI claims data leads to variability in the estimated case numbers, mortality, and health care costs. These differences are most probably in part due to the variable inclusion of inpatients who received short-term dialysis after AKI.