Estimating a Treatment Effect with Repeated Measurements Accounting for Varying Effectiveness Duration

To assess treatment efficacy in clinical trials, certain clinical outcomes are repeatedly measured for same subject over time. They can be regarded as function of time. The difference in their mean functions between the treatment arms usually characterises a treatment effect. Due to the potential existence of subject-specific treatment effectiveness lag and saturation times, erosion of treatment effect in the difference may occur during the observation period of time. Instead of using ad hoc parametric or purely nonparametric time-varying coefficients in statistical modeling, we first propose to model the treatment effectiveness durations, which are the varying time intervals between the lag and saturation times. Then some mean response models are used to include such treatment effectiveness durations. Our methodologies are demonstrated by simulations and an application to the dataset of a landmark HIV/AIDS clinical trial of short-course nevirapine against mother-to-child HIV vertical transmission during labour and delivery

Accelerated Hazards Model: Method, Theory and Applications

In an accelerated hazards model, the hazard functions of a failure time are related through the time scale-change, which is often a function of covariates and associated parameters. When the hazard functions have special properties, such as monotonicity in time, the parameters may be clinically meaningful in measuring a treatment effect. This paper reviews methodological and theoretical development of this model. Applications of the accelerated hazards model including sample size calculation in clinical trials, are also explored

Analysis of the Prevalence and Influencing Factors of Chronic Obstructive Pulmonary Disease in Elderly Hospitalized Patients：a Study Based on a Comprehensive Geriatric Assessment System in Yunnan Province

BackgroundCurrent studies on chronic obstructive pulmonary disease (hereinafter referred to as COPD) mostly focus on the lung itself, while studies on the extrapulmonary manifestations of COPD are still lacking. Many studies in China and at abroad have shown that COPD is closely related to geriatric syndrome, but it has not been further confirmed.ObjectiveTo investigate the prevalence of COPD in senile inpatients in several hospitals in Yunnan Province in the past three years, and to explore the influencing factors of elderly COPD from the aspect of geriatric syndrome.MethodsA total of 2 182 newly admitted elderly patients (≥60 years old) in several hospitals of Yunnan Province from September 2018 to June 2021 were selected as the research objects and divided into COPD group and non-COPD group according to whether the patients had COPD. The software platform of "Comprehensive Geriatric Assessment System" independently developed by the Geriatrics Department of the First People's Hospital of Yunnan Province was used to collect general data from the patients. At the same time, the scales in the system were used to conduct a comprehensive geriatric evaluation of the patients, including the assessment of anxiety and depression by 15-item geriatric depression scale (GDS-15) , the assessment of insomnia situation by athens insomnia scale (AIS) , the assessment of family support by PAGAR scale, the assessment of fall risk by Morse fall scale, the assessment of cognitive function by mini-mental state examination (MMSE) , the assessment of nutrition status by mini nutritional assessment scale, the assessment of the patients' daily living ability by the basic activities of daily living (BADL) scale, the assessment of frailty state by the Fried Scale, the assessment of swallowing (choking) by swallowing function assessment scale, the assessment of urinary incontinence by incontinence questionnaire simple form (ICI-Q-SF) , the assessment of constipation by Roma Ⅲ scale, the assessment of pain by visual analogue scale (VAS) . The influencing factors of COPD in the elderly hospitalized patients were analyzed by binary Logistic regression.ResultsThere were 1 558 cases (71.4%) in the non-COPD group and 624 cases (28.6%) in the COPD group. The results of binary Logistic regression analysis showed that age ≥75 and <85 years, age≥85 years old, male, anxiety and depression, potential malnutrition, malnutrition, pre-frailty, frailty were independent influencing factors of COPD (P<0.05) .ConclusionElderly hospitalized patients aged ≥60 years have a higher prevalence of COPD and are closely associated with geriatric syndrome

Correlation of Malnutrition，25-hydroxy Vitamin D and Interleukin-1β with Chronic Obstructive Pulmonary Disease in Elderly Inpatients

BackgroundThe specific pathogenesis of chronic obstructive pulmonary disease (COPD) is still not very clear so far, clinical interventions mainly focus on the control of pulmonary symptoms with drugs, however, the influence of extrapulmonary related factors of COPD has not caused enough attention.ObjectiveTo explore the correlation of malnutrition, 25-hydroxy vitamin D and interleukin-1β with COPD in elderly inpatients.MethodsA total of 305 inpatients (≥60 years old) were recruited from Department of Geriatrics, the First People's Hospital of Yunnan Province from November 2020 to August 2021, and divided into COPD group (n=89) and non-COPD group (n=216) according to the incidence of COPD. General information and comprehensive geriatric assessment results were compared between the two groups; binary Logistic regression analysis was used to analyze the influencing factors of COPD in elderly inpatients, and Spearman rank correlation analysis was used to analyze the correlation of malnutrition, 25-hydroxy vitamin D and interleukin-1β with COPD.ResultsThere were significant differences in age, gender, current smoking rate, nutritional status, cognitive function, incidence of anxiety and depression, incidence of disability, sleeping status, frailty status, proportion of multiple drugs, kinds of drugs used, platelet count, C-reactive protein, total protein, albumin, thyroxine, 25-hydroxy vitamin D, estradiol, testosterone, prothrombin time, D-dimer, interleukin-6 and interleukin-1β between the two groups (P<0.05) . The results of binary Logistic regression analysis showed that, current smoking〔OR=2.351, 95%CI (1.053, 5.249) 〕, underlying malnutrition〔OR=2.429, 95%CI (1.118, 5.276) 〕, malnutrition〔OR=3.936, 95%CI (1.355, 11.439) 〕, sleeplessness〔OR=2.584, 95%CI (1.094, 6.102) 〕, C-reactive protein〔OR=0.988, 95%CI (0.978, 0.999) 〕, 25-hydroxy vitamin D〔OR=0.929, 95%CI (0.880, 0.981) 〕and interleukin-1β〔OR=1.025, 95%CI (1.003, 1.047) 〕were independent influencing factors of COPD in elderly inpatients (P<0.05) . The results of Spearman rank correlation analysis showed that, malnutrition (rs=0.280, P<0.001) and interleukin-1β (rs=0.145, P=0.011) were positively correlated with the incidence of COPD in elderly inpatients, while 25-hydroxy vitamin D was negatively correlated with the incidence of COPD (rs=-0.264, P<0.001) .ConclusionMalnutrition, 25-hydroxy vitamin D and interleukin-1β are independent influencing factors of COPD in elderly inpatients. Among them, malnutrition and interleukin-1β are positively correlated with the incidence of COPD, while 25-hydroxy vitamin D is negatively correlated with the incidence of COPD

Research-based versus clinical serum creatinine measurements and the association of acute kidney injury with subsequent kidney function: findings from the Chronic Renal Insufficiency Cohort study.

Background:Observational studies relying on clinically obtained data have shown that acute kidney injury (AKI) is linked to accelerated chronic kidney disease (CKD) progression. However, prior reports lacked uniform collection of important confounders such as proteinuria and pre-AKI kidney function trajectory, and may be susceptible to ascertainment bias, as patients may be more likely to undergo kidney function testing after AKI. Methods:We studied 444 adults with CKD who participated in the prospective Chronic Renal Insufficiency Cohort (CRIC) Study and were concurrent members of a large integrated healthcare delivery system. We estimated glomerular filtration rate (eGFR) trajectories using serum creatinine measurements from (i) the CRIC research protocol (yearly) and (ii) routine clinical care. We used linear mixed effects models to evaluate the associations of AKI with acute absolute change in eGFR and post-AKI eGFR slope, and explored whether these varied by source of creatinine results. Models were adjusted for demographic characteristics, diabetes status and albuminuria. Results:During median follow-up of 8.5 years, mean rate of eGFR loss was -0.31 mL/min/1.73 m2/year overall, and 73 individuals experienced AKI (55% Stage 1). A significant interaction existed between AKI and source of serum creatinine for acute absolute change in eGFR level after discharge; in contrast, AKI was independently associated with a faster rate of eGFR decline (mean additional loss of -0.67 mL/min/1.73 m2/year), which was not impacted by source of serum creatinine. Conclusions:AKI is independently associated with subsequent steeper eGFR decline regardless of the serum creatinine source used, but the strength of association is smaller than observed in prior studies after taking into account key confounders such as pre-AKI eGFR slope and albuminuria

The p.V37I Exclusive Genotype Of GJB2: A Genetic Risk-Indicator of Postnatal Permanent Childhood Hearing Impairment

Postnatal permanent childhood hearing impairment (PCHI) is frequent (0.25%–0.99%) and difficult to detect in the early stage, which may impede the speech, language and cognitive development of affected children. Genetic tests of common variants associated with postnatal PCHI in newborns may provide an efficient way to identify those at risk. In this study, we detected a strong association of the p.V37I exclusive genotype of GJB2 with postnatal PCHI in Chinese Hans (P = 1.4×10−10; OR 62.92, 95% CI 21.27–186.12). This common genotype in Eastern Asians was present in a substantial percentage (20%) of postnatal PCHI subjects, and its prevalence was significantly increased in normal-hearing newborns who failed at least one newborn hearing screen. Our results indicated that the p.V37I exclusive genotype of GJB2 may cause subclinical hearing impairment at birth and increases risk for postnatal PCHI. Genetic testing of GJB2 in East Asian newborns will facilitate prompt detection and intervention of postnatal PCHI

Prevalence of cardiovascular disease and risk factors in a rural district of Beijing, China: a population-based survey of 58,308 residents

Abstract Background Cardiovascular disease (CVD) is the leading cause of global disease burden. Although stroke was thought to be more prevalent than coronary heart disease (CHD) in Chinese, the epidemic pattern might have been changed in some rural areas nowadays. This study was to estimate up-to-date prevalence of CVD and its risk factors in rural communities of Fangshan District, Beijing, China. Methods A cross-sectional population survey was carried out by stratified cluster sampling. A total of 58,308 rural residents aged over 40 years were surveyed by face-to-face interview and physical examination during 2008 and 2010. The standardized prevalence was calculated according to adult sample data of China's 5th Population Census in 2000, and the adjusted prevalence odds ratio (POR) was calculated for the association of CHD/stroke with its cardiovascular risk factors in multivariate logistic regression models. Results Age- and sex-standardized prevalence was 5.6% for CHD (5.2% in males and 5.9% in females), higher than the counterpart of 3.7% (4.7% in males and 2.6% in females) for stroke. Compared with previous studies, higher prevalence of 7.7%, 47.2%, 53.3% in males and 8.2%, 44.8%, 60.7% in females for diabetes, hypertension and overweight/obesity were presented accordingly. Moreover, adjusted POR (95% confidence interval) of diabetes, obesity, stage 1 and stage 2 hypertension for CHD as 2.51 (2.29 to 2.75), 1.53 (1.38 to 1.70), 1.13 (1.02 to 1.26) and 1.35 (1.20 to 1.52), and for stroke as 2.24 (1.98 to 2.52), 1.25 (1.09 to 1.44), 1.44 (1.25 to 1.66) and 1.70 (1.46 to 1.98) were shown respectively in the multivariate logistic regression models. Conclusions High prevalence of CVD and probably changed epidemic pattern in rural communities of Beijing, together with the prevalent cardiovascular risk factors and population aging, might cause public health challenges in rural Chinese population

Anemia and risk for cognitive decline in chronic kidney disease

BACKGROUND: Anemia is common among patients with chronic kidney disease (CKD) but its health consequences are poorly defined. The aim of this study was to determine the relationship between anemia and cognitive decline in older adults with CKD. METHODS: We studied a subgroup of 762 adults age ≥55 years with CKD participating in the Chronic Renal Insufficiency Cohort (CRIC) study. Anemia was defined according to the World Health Organization criteria (hemoglobin <13 g/dL for men and <12 g/dL for women). Cognitive function was assessed annually with a battery of six tests. We used logistic regression to determine the association between anemia and baseline cognitive impairment on each test, defined as a cognitive score more than one standard deviation from the mean, and mixed effects models to determine the relation between anemia and change in cognitive function during follow-up after adjustment for demographic and clinical characteristics. RESULTS: Of 762 participants with mean estimated glomerular filtration rate of 42.7 ± 16.4 ml/min/1.73 m(2), 349 (46 %) had anemia. Anemia was not independently associated with baseline cognitive impairment on any test after adjustment for demographic and clinical characteristics. Over a median 2.9 (IQR 2.6–3.0) years of follow-up, there was no independent association between anemia and change in cognitive function on any of the six cognitive tests. CONCLUSIONS: Among older adults with CKD, anemia was not independently associated with baseline cognitive function or decline. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12882-016-0226-6) contains supplementary material, which is available to authorized users