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Background: Diabetes mellitus is known to have a negative effect on colorectal cancer survival due to hyperinsulinemia or hyperglycemia, and medications such as metformin, which targets insulin resistance and hyperinsulinemia, have a preventive effect on the risk of death. The aim of this study was to compare the risk of death among patients with colorectal cancer with diabetes with different levels of adherence to oral antidiabetics. Methods: National Health Information Database was used, which has all claims data for those who are registered for national health insurance in Korea, from 2002 to 2016, for conducting a retrospective cohort study. Newly diagnosed patients with colorectal cancer among diabetics were followed up from the date of diagnosis until death or December 31, 2016. The medication adherence was calculated as the proportion of days covered (PDC). The HR and 95% confidence interval (CI) for death were estimated using the low-adherence patients as a reference. Results: A total of 33,841 diabetic patients with newly diagnosed colorectal cancer were followed for an average of 4.7 years. Patients with colorectal cancer with good adherence (PDC ≥ 80%) showed a reduced risk of death [HR (95% CI), 0.82 (0.78-0.86)] compared with those with poor adherence (PDC < 80%). A reduced risk of death was observed for all cancer subsites. Conclusions: The maintenance of good medication adherence for diabetes mellitus was related to a favorable prognosis of colorectal cancer. Impact: This study provides evidence that patients with colorectal cancer who are adherent to their diabetes medication will have better survival than patients who are not adherent. [ABSTRACT FROM AUTHOR]

We propose methods of linear transceiver design for two different power constraints, sum relay power constraint and per relay power constraint, which determine signal processing matrices such as base station (BS) transmitter, relay precoders and user receivers to minimize sum mean square error (SMSE) for multi-relay multi-user (MRMU) networks. However, since the formulated problem is non-convex one which is hard to be solved, we suboptimally solve the problems by defining convex subproblems with some fixed variables. We adopt iterative sequential designs of which each iteration stage corresponds to each subproblem. Karush-Kuhn-Tucker (KKT) theorem and SMSE duality are employed as specific methods to solve subproblems. The numerical results verify that the proposed methods provide comparable performance to that of a full relay cooperation bound (FRCB) method while outperforming the simple amplify-and-forward (SAF) and minimum mean square error (MMSE) relaying in terms of not only SMSE, but also the sum rate. [ABSTRACT FROM AUTHOR]

In this paper, we propose an iterative transceiver design in a multi-relay multi-user multiple-input multiple-output (MIMO) system. The design criterion is to minimize sum mean squared error (SMSE) under relay sum power constraint (RSPC) where only local channel state information (CSI)s are available at relays. Local CSI at a relay is defined as the CSI of the channel between BS and the relay in the 1st hop link, and the CSI of the channel between the relay and all users in the 2nd hop link. Exploiting BS transmitter structure which is concatenated with block diagonalization (BD) precoder, each relay's precoder can be determined using local CSI at the relay. The proposed scheme is based on sequential iteration of two stages; stage 1 determines BS transmitter and relay precoders jointly with SMSE duality, and stage 2 determines user receivers. We verify that the proposed scheme outperforms simple amplify-and-forward (SAF), minimum mean squared error (MMSE) relay, and an existing good scheme of [13] in terms of both SMSE and sum-rate performances. [ABSTRACT FROM AUTHOR]