Higher rates of surgical and medical complications and mortality following TKA in patients aged ≥ 80 years: a systematic review of comparative studies

The purpose of this systematic review was to synthesize studies published since the last systematic review in 2015 that compare outcomes of primary total knee arthroplasty (TKA) in older patients (≥ 80 years) and in younger patients (< 80 years), in terms of complication rates and mortality. An electronic literature search was conducted using PubMed, Embase®, and Cochrane Register. Studies were included if they compared outcomes of primary TKA for osteoarthritis in patients aged 80 years and over to patients aged under 80 years, in terms of complication rates, mortality, or patient-reported outcomes (PROs). Thirteen studies were eligible. Surgical complications in older patients ranged from 0.6–21.1%, while in younger patients they ranged from 0.3–14.6%. Wound complications in older patients ranged from 0.5–20%, while in younger patients they ranged from 0.8–22.0%. Medical complications (cardiac, respiratory, thromboembolic) in older patients ranged from 0.4–17.3%, while in younger patients they ranged from 0.2–11.5%. Mortality within 90 days in older patients ranged between 0–2%, while in younger patients it ranged between 0.0–0.03%. Compared to younger patients, older patients have higher rates of surgical and medical complications, as well as higher mortality following TKA. The literature also reports greater length of stay for older patients, but inconsistent findings regarding PROs. The present findings provide surgeons and older patients with clearer updated evidence, to make informed decisions regarding TKA, considering the risks and benefits within this age group. Patients aged over 80 years should therefore not be excluded from consideration for primary TKA based on age alone. Cite this article: EFORT Open Rev 2021;6:1052-1062. DOI: 10.1302/2058-5241.6.200150

Doxycycline exposure during adolescence and future risk of non-affective psychosis and bipolar disorder: a total population cohort study

Doxycycline has been hypothesized to prevent development of severe mental illness (SMI) through the suppression of microglia, especially if administered during the intense synaptic pruning period of adolescence. However, results from register studies on potential benefits differ considerably. The aim of the present study was to determine whether doxycycline exposure during adolescence is associated with reduced SMI risk, and to investigate if a direct and specific causality is plausible. This is a Swedish national population register-based cohort study of all individuals born from 1993 to 1997, followed from the age of 13 until end of study at the end of 2016. The primary exposure was cumulative doxycycline prescription ≥3000 mg and outcomes were first diagnosis of non-affective psychosis (F20–F29) and first diagnosis of bipolar disorder (F30–F31). Causal effects were explored through Cox regressions with relevant covariates and secondary analyses of multilevel exposure and comparison to other antibiotics. We found no association between doxycycline exposure and risk of subsequent non-affective psychosis (adjusted hazard ratio (HR) 1.15, 95% CI 0.73–1.81, p = 0.541) and an increased risk of subsequent bipolar disorder (adjusted HR 1.95, 95% CI 1.49–2.55, p < 0.001). We do not believe the association between doxycycline and bipolar disorder is causal as similar associations were observed for other common antibiotics.

The influence of the benchmark corpus on keyword analysis

The growing popularity of keyword analysis as an applied linguistics methodology has not been matched by an increase in the rigour with which the method is applied. While several studies have investigated the impact of choices made at certain stages of the keyword analysis process, the impact of the choice of benchmark corpus has largely been overlooked. In this paper, we compare a target corpus with several benchmark corpora and show that the keywords generated are different. We also show that certain characteristics of the keyword list and of the keywords themselves vary in relatively predictable ways depending on the benchmark corpus. These variations have implications for the choice of benchmark corpus and how the results of a keyword analysis should be interpreted. Analyzing the keywords from a comparison with a large general corpus or the keyword lists from multiple comparisons may be most appropriate for register studies.

Register and Register Variation

Register research has been approached from differing theoretical and methodological approaches, resulting in different definitions of the term register. In the text-linguistic approach, which is the primary focus of this bibliography, register refers to text varieties that are defined by their situational characteristics, such as the purpose of writing and the mode of communication, among others. Texts that are similar in their situational characteristics also tend to share similar linguistic profiles, as situational characteristics motivate or require the use of specific linguistic features. Text-linguistic research on register tends to focus on two aspects: attempts to describe a register, or attempts to understand patterns of register variation. This research happens via comparative analyses, specific examinations of single linguistic features or situational parameters, and often via examinations of co-occurrence of linguistic features that are analyzed from a functional perspective. That is, certain lexico-grammatical features co-occur in a given text because they together serve important communicative functions that are motivated by the situational characteristics of the text (e.g., communicative purpose, mode, setting, interactivity). Furthermore, corpus methods are often relied upon in register studies, which allows for large-scale examinations of both general and specialized registers. Thus, the bibliography gives priority to research that uses corpus tools and methods. Finally, while the broadest examinations on register focus on the distinction between written and spoken domains, additional divisions of register studies fall under the categories of written registers, spoken registers, academic registers, historical registers, and electronic/online registers. This bibliography primarily introduces some of the key resources on English registers, a decision that was made to reach a broader audience.

Current trends in Corpus Linguistics and textual variation

Corpus Linguistics has proved of great value as a methodological tool in shedding light on how discourse is constructed in different text types. This opening contribution to the special issue “Corpus-linguistic perspectives on textual variation” provides an account of some of the most common applications of Corpus Linguistics, describes some of the most widely used corpora, and pins down some of the most influential corpus-based research works. In so doing, we contextualise the contributions to this collection of articles. The main aim of this special issue is to showcase cutting-edge research on textual variation based on linguistic corpora, thus illustrating how Corpus Linguistics draws from but also feeds a multiplicity of linguistic branches, such as (Critical) Discourse Analysis, Register Studies, Historical Linguistics, and Dialectology.

Preliminary Studies on Register Function of Chinese Function Words

This paper explores the effectiveness of Chinese function words in register studies based on text mining and attempts to determine their register specific functions based on quantitative methods. Following the hypothesis that function words can be used as features to differentiate different registers, our text clustering experiment demonstrates that different registers in Chinese can in fact be classified in terms of distribution of function words. Our correspondence analysis shows that the correlations between function words and different registers vary, hence some function words have register-specific functions. In addition, the correlation coefficients between function words and various registers can determine the register-specific function of function words. Our quantitative model of register specific function of function words makes an important contribution to our understanding of the correlation between function words and registers.

Fiction – one register or two?

In this paper our focus is on analyzing register variation within fiction, rather than between fiction and other registers. By working with subcorpora that separate text within and outside of quotation marks, we appromixate fictional speech and narration. This enables us to identify and compare linguistic features with regard to different situational contexts in the fictional world. We focus in particular on the novels of Charles Dickens and a reference corpus of other 19th-century fiction. Our main method for the register analysis is Multi-dimensional Analysis (MDA) for which we draw on altogether four dimensions from two previous MDAs. The linguistic distinctions we identify highlight similarities between fictional speech and involved registers such as face-to-face communication, and between narration and more informational and narrative prose. In addition to the detailed information on register features that characterize speech and narration, the paper raises more general questions about the ability of register studies to deal with situational contexts within fiction.