1,721,293 research outputs found
Associations between chronic kidney disease and age-related macular degeneration
No full textPurpose: age-related macular degeneration (AMD) and renal impairment are both associated with cardiovascular risk factors and with alterations in the complement pathways. There are few data on the association of AMD with chronic kidney disease. Methods: people who were visually impaired (binocular acuity < 6/18) due to AMD (ascertained from review of medical notes; n = 516) were compared to people with normal vision (6/6 or better; n = 2755). Cases with AMD and controls derive from a population-based cross-sectional study of people aged 75 years and over registered with 49 family practices in Britain. Glomerular filtration rate (eGFR) was estimated with the Modification of Diet in Renal Disease formula and proteinuria assessed by dipsticks. Results: after adjusting for a wide range of confounding factors, the presence of proteinuria was positively associated with AMD among men (odds ratio (OR) 2.06, 95% confidence interval (CI) 1.05, 4.04) but not in women (OR 0.62 95%CI 0.36,1.08). Among men, eGFR < 45 ml/min/1.73 m2 was associated with AMD but not after adjusting for proteinuria. This was not observed for women. Both proteinuria and eGFR showed different associations with AMD by sex (p-values for interaction < 0.05). Conclusions: proteinuria appears to be a risk factor for AMD among men but not among women, possibly due to measurement errors in detecting proteinuria in wome
Patterns and effects of missing comorbidity data for patients starting renal replacement therapy in England, Wales and Northern Ireland
No full textBackground. Renal Registries play a key role in assessing quality of care and outcomes of renal replacement therapy and comparisons of outcomes between groups should adjust for differences in comorbidities. This study aimed to describe patterns of missing comorbidity data and differences in survival between patients with comorbidity data returned and those with missing comorbidity data. Methods. Trends in comorbidity data returns by year (1998–2006) and within centres were examined using descriptive statistics. Survival of patients was described using Kaplan–Meier graphs (log-rank tests) and hazard ratios were calculated using Cox proportional hazard models. Last follow-up was at 31 December 2007. A range of sensitivity analyses were carried out, including multiple imputation. Results. Among 34 059 patients, there were 62% who had no comorbidity data. The completeness of comorbidity data increased markedly from 17% in 1998 to 47% in 2003, but had fallen back to 37% by the year 2006. Those with a missing comorbidity generally do considerably worse than those without the comorbidity and in most cases more closely follow the survival curve of those with the comorbidity. Multiple imputation analysis suggested that those with missing information on comorbidity have higher prevalence of comorbidity than seen in those with available data. Treating missing comorbidity entries as indication of absent comorbidity (i.e. a tick only if yes policy) would lead to an attenuation of the effect of comorbidity on survival. Conclusions. Missing data lead to difficulties in performing between centre comparisons. A ‘tick if present policy’ in comorbidity data collection should be discouraged. Much more work is needed to fully understand why levels of missing comorbidity data are so high and to identify strategies to improve recording. <br/
Urbanization and internal migration as risk factors for non-communicable diseases in Thailand
Full text linkUrbanization, which is driven mainly by the expansion of cities and urban
migration, is considered one of the key drivers of non-communicable
diseases (NCDs) in developing countries. This research aims to investigate
the patterns and associations between different levels of urban exposures
and NCD risk factors, NCD morbidity and NCD mortality in Thailand, to better
understand the mechanisms underlying the link between urbanization and
NCD in Thailand.
Using several study designs and analytical techniques, the research
described in this thesis found that the process of migration and living in an
urban environment were associated with lower social trust and higher levels
of emotional problems. Urban environments were also associated with
behavioural and physiological risk factors for NCDs, including smoking,
heavy alcohol consumption, inadequate physical activity, inadequate
fruit/vegetable consumption, high BMI, and high blood pressure. Both early
life urban exposure and accumulation of urban exposure throughout life
potentially play a role in these increases in behavioural and physiological risk
factors for NCDs. Early life urban exposure was also found to be associated
with an increased risk of developing obesity in adulthood.
Increased psychosocial, behavioural and physiological risk factors
associated with living in an urban environment may not translate directly into
increased prevalence of biological risk factors for NCDs (such as high
cholesterol), the development of NCDs, or into NCD-related mortality. It is
likely that biological risk factors for NCDs, as well as NCD incidence and
mortality are more amendable to change from the positive influences of
urbanization through higher socioeconomic status and potential access to
better health care
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Associations between chronic kidney disease and mental health disorders and psychoactive drugs in the UK general population
Full text linkThis thesis examined the association between chronic kidney disease (CKD) and both mental health disorders and psychoactive drugs, using a large contemporary UK database of routine medical record data (Clinical Practice Research Datalink [CPRD]). To fill the gap between what is known and what is unknown in this field, I focused on two main topics: (i) severe mental illness (SMI), with and without a history of lithium use, and CKD, and (ii) CKD and antidepressants (mainly prescribed for common mental health disorders such as depression and anxiety) and associated serious adverse outcomes. I first conducted a population-level validation study comparing prevalence estimates of decreased kidney function (defined as estimated glomerular filtration rate of <60 ml/min/1.73 m2) and renal replacement therapy (RRT) in the CPRD population with nationally representative statistics (Health Survey for England and UK Renal Registry). Findings suggested that most patients with decreased kidney function and RRT are probably captured in the CPRD. Secondly, I conducted a cross-sectional study on the association between SMI, including schizophrenia and bipolar disorder, and CKD (defined as two measurements of estimated glomerular filtration rate of <60 ml/min/1.73 m2 over ≥3 months in the past five years). Patients with SMI, especially lithium users, had a significantly higher prevalence of both CKD and RRT than the general population. Thirdly, I conducted a matched cohort study comparing the prevalence and incidence of antidepressant prescription between patients with and without CKD (matched for age, sex, general practice, and calendar time). Patients with CKD were approximately one and a half times more likely to receive antidepressants for mental health conditions such as depression and anxiety. Finally, I examined the gastrointestinal (GI) bleeding risk of selective serotonin reuptake inhibitors (SSRIs) by level of kidney function. While the relative risk for GI bleeding associated with SSRIs (i.e. the fully-adjusted rate ratio between periods with and without SSRI prescription) was constant regardless of baseline kidney function, the excess risk for GI bleeding associated with SSRIs (i.e. the fully-adjusted rate difference between periods with and without SSRI exposure) increased markedly as baseline kidney function deteriorated. In conclusion, a close association between CKD and mental health disorders was suggested in the UK general population. It is evident that patients with CKD are more likely to be prescribed antidepressants, and this may cause serious adverse outcomes such as GI bleeding associated with SSRIs. The risk-benefit balance of antidepressants for patients with CKD may need to be reconsidered in light of this new evidence
CKD and mortality risk in older people: a community-based population study in the United Kingdom
No full textBackground: the prevalence of chronic kidney disease (CKD) increases with age; however, theprognostic significance in older people is uncertain. This study aims to determine the association of CKDwith all-cause and cardiovascular mortality in community-dwelling older people 75 years and older.Study Design: Cohort study of people 75 years and older recruited in 1994 to 1999 to 1 arm of a trialof multidimensional health assessment with mortality follow-up.Setting & Participants: 53 general practices in Great Britain. 15,336 (73%) of those eligibleparticipated. 13,177 (86%) had serum creatinine measured at baseline.Main Factor: estimated glomerular filtration rate (eGFR).Outcomes: All-cause and cardiovascular mortality.Measurements: eGFR derived from serum creatinine level using the 4-variable Modification of Diet inRenal Disease (MDRD) Study equation in milliliters per minute per 1.73 m2; dipstick proteinuria.Mortality by linkage to national death registration and death certification.Results: after a median follow-up of 7.3 years (interquartile range, 5.0), 7,633 (58%) had died, 42% ofcardiovascular causes. In the first 2 years of follow-up, adjusted hazard ratios for all-cause mortality ineGFR bands of 45 to 59, 30 to 44, and less than 30 compared with eGFR greater than 60 mL/min/1.73m2 were 1.13 (95% confidence interval, 0.93 to 1.37), 1.69 (95% confidence interval, 1.26 to 2.28), and3.87 (95% confidence interval, 2.78 to 5.38) in men and 1.14 (95% confidence interval, 0.93 to 1.40),1.33 (95% confidence interval, 1.06 to 1.68), and 2.44 (95% confidence interval, 1.68 to 3.56) in women,respectively. Hazard ratios were greater for cardiovascular mortality and lower after 2 years. Dipstickproteinuria was independently associated with all-cause, but not cardiovascular, mortality risk in bothsexes.Limitations: single serum creatinine measurement, no calibration of serum creatinine, MDRD Studyequation not validated in older people.Conclusion: As kidney function decreases, there is a graded and independent increase in all-causeand cardiovascular mortality risk in older people 75 years and older, especially in men and those witheGFR less than 45 mL/min/1.73 m2. Dipstick proteinuria did not add to cardiovascular mortality risk inthis elderly population. In older people, identification and management of CKD should prioritize thesmaller numbers with more severe CKD
Impairment of kidney function and reduced quality-of-life in older people: a cross-sectional study
No full textObjective: to assess the association of kidney function with quality-of-life in community-dwelling older adults aged 75 years or more in the UK.Design: cross-sectional study.Setting: primary care; 12 UK general practices participating in a cluster trial of health screening.Subjects: estimated glomerular filtration rate (eGFR, ml/min/1.73 m2) using the four-variable modified diet in renal disease equation was derived in 1,195 men and 1,772 women with available bloods, these were 92% of 3,211 study participants who consented to interviews and 73% of those invited into the original cluster trial of health screening.Main outcome measures: interviews by trained fieldworker using the Sickness Impact Profile (home management, mobility, self-care, social interaction), and the Philadelphia Geriatric Morale Scale. Higher scores imply worse quality-of-life in a given domain.Results: in age- and co-morbidity-adjusted analyses there was an association of eGFR <45 and the highest scores (defined as ?median) of mobility (men: odds ratio (OR) 2.91, 95% confidence interval (CI) 1.56–5.41; women: OR 1.73, 95% CI 1.02–2.94), home management (men: OR 1.49, 95% CI 1.09–2.04; women: OR 3.50, 95% CI 1.18–10.35), social interaction (men: OR 3.34, 95% CI 1.73–6.45; women: 2.64, 95% CI 1.61–4.33) when compared with those with eGFR ?60 and who reported no problems. Men with eGFR <45 had low morale (OR 2.45, 95% CI 1.02–5.87) but this was not found for women (OR 1.40, 95% CI 0.65–3.04), whereas women (but not men) with eGFR <45 reported problems with body care (women: OR 1.68; 95% CI 1.25–2.27: men: OR 0.89, 95% CI 0.55–1.46).Conclusions: an eGFR <45 is associated with poorer quality-of-life at older age. More research is needed to identify modifiable causes to improve quality-of-life in older people with such a degree of kidney function impairmen
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