Working papers of the Max Planck Institute for Demographic Research receive only limited review. Views or opinions expressed in working papers are attributable to the authors and do not necessarily reflect those of the Institute.

OBJECTIVE To determine the association between plasma brain natriuretic peptide (BNP) level in patients with heart failure (HF) and physical frailty as well as with each domain of physical frailty. METHODS Two hundred and six outpatients of cardiovascular medicine aged 60 years and older who had been hospitalized for HF or had been given a prescription medication for HF were included. Physica...

The Gompertz distribution has many applications, particularly in medical and actuarial studies. However, there has been little recent work on the Gompertz in comparison with its early investigation. The problem of analyzing and estimating parameters of bivariate Gompertz distribution with shared frailty is of interest and the focus of this paper. We propose maximum likelihood estimation procedu...

In this paper, the problem of identifying s correlated components from a p−dimensional Gaussian vector is considered. Instead of having to take a full-vector observation at each time index, the observer is allowed to observe any subset or full set of components in the vector, and he has the freedom to design his sampling strategies over time. The observer aims to find an optimal sampling strate...

BACKGROUND Uncomplicated frailty instruments are desirable for use in a busy clinical setting. The aim of this study was to operationalize a frailty index (FI) from routine blood and urine tests, and to evaluate the properties of this FI compared to other frailty instruments. MATERIALS AND METHODS We conducted a secondary analysis of a prospective cohort study on 306 patients aged ≥65 years h...

BACKGROUND The incidence of chronic kidney disease (CKD) is rising and is likely to continue to do so for the foreseeable future, with the fastest growth seen among adults ≥75 years of age. Elderly patients with advanced CKD are likely to have a higher burden of comorbidity and frailty, both of which may influence their disease outcome. For these patients, treatment decisions can be complex, wi...

Three correlated frailty models are used to analyze bivariate timeto-event data by assuming gamma, log-normal and compound Poisson distributed frailty. All approaches allow to deal with right censored lifetime data and account for heterogeneity as well as for a non-susceptible (cure) fraction in the study population. In the gamma and compound Poisson model traditional ML estimation methods are ...