Development and external validation of an acute kidney injury risk score for use in the general population.

BACKGROUND: Improving recognition of patients at increased risk of acute kidney injury (AKI) in the community may facilitate earlier detection and implementation of proactive prevention measures that mitigate the impact of AKI. The aim of this study was to develop and externally validate a practical risk score to predict the risk of AKI in either hospital or community settings using routinely collected data. METHODS: Routinely collected linked datasets from Tayside, Scotland, were used to develop the risk score and datasets from Kent in the UK and Alberta in Canada were used to externally validate it. AKI was defined using the Kidney Disease: Improving Global Outcomes serum creatinine-based criteria. Multivariable logistic regression analysis was performed with occurrence of AKI within 1 year as the dependent variable. Model performance was determined by assessing discrimination (C-statistic) and calibration. RESULTS: The risk score was developed in 273 450 patients from the Tayside region of Scotland and externally validated into two populations: 218 091 individuals from Kent, UK and 1 173 607 individuals from Alberta, Canada. Four variables were independent predictors for AKI by logistic regression: older age, lower baseline estimated glomerular filtration rate, diabetes and heart failure. A risk score including these four variables had good predictive performance, with a C-statistic of 0.80 [95% confidence interval (CI) 0.80-0.81] in the development cohort and 0.71 (95% CI 0.70-0.72) in the Kent, UK external validation cohort and 0.76 (95% CI 0.75-0.76) in the Canadian validation cohort. CONCLUSION: We have devised and externally validated a simple risk score from routinely collected data that can aid both primary and secondary care physicians in identifying patients at high risk of AKI.

Acute kidney injury and critical limb ischaemia associated with the use of the so called "legal high" 3-fluorophenmetrazine.

Until the law in the United Kingdom (UK) changed in May 2016 so called "legal highs" or "new psychoactive substances" were freely available in high street shops across the UK. Following prohibition these drugs are still easily purchased illegally via the internet. We report a case of a patient who self-administered 3-fluorophenmetrazine intravenously with catastrophic consequences. Adverse effects were almost immediate with symptoms of malaise and tachycardia. Two days post administration he was transferred to the intensive therapy unit with acute kidney injury and irreversible four limb ischaemia. He required a period of renal replacement therapy and bilateral lower limb amputation. This case highlights the fact that new psychoactive substances have many unintended adverse effect which have not been previously described. Multiple routes of administration are used by people taking these agents including intravenously. Medical practitioners should always consider ingestion of new psychoactive substances in the differential diagnosis of acutely ill patients.

Older people remain on blood pressure agents despite being hypotensive resulting in increased mortality and hospital admission.

BACKGROUND: the use of antihypertensive medication in older people in order to prevent cardiovascular events is well established. The use of such agents has been encouraged by incentive schemes in the United Kingdom including the Quality and Outcomes Framework. In addition, many guidelines recommend good blood pressure (BP) control in the elderly. However, in older people antihypertensives can cause adverse effects related to hypotension. AIM: the aim of this study was to assess the prevalence of low BP and impact on outcomes, particularly in the presence of antihypertensive treatment, in a primary care population of older people. DESIGN: a retrospective observational cohort study in people over the age of 70 years registered with primary care providers in Kent. RESULTS: a total of 11,167 patients over 70 years old were analysed, 6,373 female (57%). Systolic blood pressure (SBP) was below 120 mmHg in 1,297 people (844 on antihypertensives), below 110 mmHg in 474 (313 on antihypertensives) and below 100 mmHg in 128 (89 on antihypertensives). Hypotension was independently associated with mortality, acute kidney injury and hospital admission. CONCLUSIONS: the results demonstrate that low SBP is associated with adverse events, it is possible that the pursuit of BP control at a population level may lead to over-treatment in certain groups of patients. This may result in an increased incidence of adverse events particularly in older people.