Combining machine learning and conventional statistical approaches for risk factor discovery in a large cohort study.

We present a simple and efficient hypothesis-free machine learning pipeline for risk factor discovery that accounts for non-linearity and interaction in large biomedical databases with minimal variable pre-processing. In this study, mortality models were built using gradient boosting decision trees (GBDT) and important predictors were identified using a Shapley values-based feature attribution method, SHAP values. Cox models controlled for false discovery rate were used for confounder adjustment, interpretability, and further validation. The pipeline was tested using information from 502,506 UK Biobank participants, aged 37-73 years at recruitment and followed over seven years for mortality registrations. From the 11,639 predictors included in GBDT, 193 potential risk factors had SHAP values ≥ 0.05, passed the correlation test, and were selected for further modelling. Of the total variable importance summed up, 60% was directly health related, and baseline characteristics, sociodemographics, and lifestyle factors each contributed about 10%. Cox models adjusted for baseline characteristics, showed evidence for an association with mortality for 166 out of the 193 predictors. These included mostly well-known risk factors (e.g., age, sex, ethnicity, education, material deprivation, smoking, physical activity, self-rated health, BMI, and many disease outcomes). For 19 predictors we saw evidence for an association in the unadjusted but not adjusted analyses, suggesting bias by confounding. Our GBDT-SHAP pipeline was able to identify relevant predictors 'hidden' within thousands of variables, providing an efficient and pragmatic solution for the first stage of hypothesis free risk factor identification.

[Prognostic factors on mortality in patients admitted to hospital with heart failure]. / Factores predictores de mortalidad en pacientes hospitalizados por insuficiencia cardíaca.

BACKGROUND: Heart failure (HF) is the leading cause of hospitalization for aging populations in Western countries, and is showing an increasing mortality. The aim of this study was to assess the probable long-term mortality risk factors for patients admitted because of HF. METHODS: Retrospective study of a cohort of 202 patients consecutively hospitalized because of HF and followed up for a maximum period of 5 years. Clinical and epidemiological factors and their relationship to in-hospital and long-term mortality were analyzed. RESULTS: In-hospital mortality was 16%.The independent predictors were: age >75 years (HR?=?2.68, 95%?IC: 1.65-4.36, p?=?0.001); cognitive impairment (HR?=?2.77, 95%?IC: 1.40-5.48, p?=?0.004); Barthel index =60 (HR?=?0.54, 95%?IC: 0.37-0.78, p?=?0,009); creatinine levels >1.16 mg/dl at admission (HR?=?1.57, 95%?IC: 1.12-2.20, p?=?0.009); and number of diagnostics >10 on discharge (HR?=?1. 64, 95%?IC: 1.14-2.36, p?=?0.007). Accumulated mortality at 12, 24, 36 and 48 months after hospital discharge were 43%, 51%, 67% and 70%, respectively; the independent predictors for this were: age >75 years (HR?=?2.55, 95%?IC: 1.56-4.15, p?<0.001); cognitive impairment (HR?=?2.45, 95%?IC: 1.22-4.90, p?=?0.011); creatinine levels >1.16 mg/dl on admission (HR?=?1.59, 95%?IC: 1.12-2.24, p?=?0.009); systolic blood pressure >140 mm Hg on admission (HR?=?0.56, 95%?IC: 0.40-0.80, p?<0.001); and number of diagnostics >10 on discharge (HR?=?1. 49, 95%?IC: 1.03-2.16, p?=?0.033). CONCLUSIONS: Clinical and epidemiological factors related to in-hospital and long-term mortality could help to improve the management of patients with HF.

Survival among the older adults with clinical signs of Lewy body dementia in 40 Swedish nursing homes: a 6-year follow-up study.

OBJECTIVES: To investigate survival among elderly residents of Swedish nursing homes (NHs), with specific focus on those with two or more signs of Lewy body dementia (LBD). DESIGN: Prospective observational study. SETTING: NHs in Malmö, the third largest city in Sweden. PARTICIPANTS: The study population was older adults (aged ≥65 years) living in the 40 NHs in Malmö. Clinical data were collected with a customised questionnaire assessing core clinical LBD signs. Patients were categorised based on 0-1 or 2-4 LBD signs. The head nurse at each NH collected the study data: LBD questionnaires, electronic medication lists and electronic medical records from 2012 to 2013. MAIN OUTCOME MEASURES: 80-month mortality. RESULTS: Five hundred and fifty-eight (96%) of the residents were deceased at follow-up; among these, mean (95% CI) overall survival time was 29 (28-31) months. Mean survival differed between the LBD groups; those with 0-1 LBD signs lived 8 months longer than those with 2-4 LBD signs. Mortality risk for residents in the LBD 2-4 group was also significantly higher. HR adjusted for age and sex was HR (95% CI) 1.60 (1.30 to 1.97). Mortality risk was also significantly higher in residents with signs of fluctuating cognition 1.36 (1.15 to 1.62), rapid eye movement sleep behaviour disorder 1.49 (1.11 to 1.98), balance problems 1.36 (1.14 to 1.61) or rigidity 1.41 (1.18 to 1.68). CONCLUSIONS: This large, longitudinal study shows the important survival effects of identifying and diagnosing older adults NH residents who have two or more LBD signs.

Bedside mental status and outcome in elderly patients admitted for acute coronary syndromes.

OBJECTIVE: We investigated whether mental status assessed by simple bedside tests in elderly patients admitted for acute coronary syndromes (ACS) was associated with higher risk of mortality. METHODS: We used the data from a prospective, open, ongoing cohort of patients≥75 years old admitted for ACS to a tertiary centre. Cognitive impairment (CogI) was defined by delirium detected by the Confusion Assessment Method or an abnormal Mini Mental State Examination score. A Cox model adjusted on predefined correlates of mortality was used to assess the relationship between CogI and 1-year mortality. RESULTS: Six-hundred consecutive patients with mental status assessment within 48 hours after admission were included. CogI was identified in 172 (29%) patients among whom 153 (25.5%) had an abnormal Mini Mental State Evaluation and 19 (3.2%) delirium. Death occurred in 49 (28.6%) patients with and 43 (10.5%) patients without CogI at 1 year. There was a significant association between CogI and 1-year mortality (adjusted-HR 2.4, 95% CI 1.53 to 3.62), p<0.001) independent of other covariables. CogI was also independently associated with higher rates of in-hospital bleeding and mortality as well as 3-month rates of all-cause, cardiovascular-related and heart failure-related rehospitalisation. CONCLUSIONS: CogI detected by simple bedside tests in patients≥75 admitted for ACS is associated with an increased risk of 1-year mortality and 3 month rehospitalisation independent of other correlates of poor outcome.

Post-sepsis syndrome - an evolving entity that afflicts survivors of sepsis.

BACKGROUND: The sequelae of sepsis were once thought to be independent of sepsis itself and assumed to be either comorbid to sick patients or complications of critical illness. Recent studies have reported consistent patterns of functional disabilities in sepsis survivors that can last from months to years after symptoms of active sepsis had resolved. BODY: Post-sepsis syndrome is an emerging pathological entity that has garnered significant interest amongst clinicians and researchers over the last two decades. It is marked by a significantly increased risk of death and a poor health-related quality of life associated with a constellation of long-term effects that persist following the patient's bout with sepsis. These include neurocognitive impairment, functional disability, psychological deficits, and worsening medical conditions. CONCLUSION: This "post-sepsis syndrome" has been the subject of active preclinical and clinical research providing new mechanistic insights and approaches linked to survivor well-being. Here we review important aspects of these research efforts and goals of care for patients who survive sepsis.

Relationships between residual blood pressure variability and cognitive function in the general population of the PAMELA study.

The present study was aimed at assessing the relationships between absolute and individual residual blood pressure (BP) variability and cognitive function in a general population. This cross-sectional study evaluated cognitive function using minimental state evaluation (MMSE) in 471 subjects enrolled in the PAMELA study. MMSE was calculated 10 years after initial enrollment of the subjects in the PAMELA study. Measurements included office, home, and 24-hour ambulatory BP monitoring. BP variability was obtained by calculating: (a) 24-hour standard deviation (SD) for systolic and diastolic BP and (b) individual residual BP variability. Mean age (±SD) of the subjects enrolled was 63 ± 5.7 years at the initial evaluation, with a 10-year increase when MMSE was performed. There was no significant difference in BP or heart rate values measured at office, home, or during 24-h BP monitoring between subjects with MMSE < 24 and those with ≥24. BP variability measured by SBP and DBP SD was also similar between these two groups. However, individual residual BP variability was significantly greater in subjects with lower MMSE and this difference became more pronounced when the study population was divided in three groups according to MMSE score (10-20, 21-23, 24-30). Individual residual SBP and DBP variability gradually decreased with the increase in MMSE score. Our data show that a sensitive parameter for the development of cognitive impairment is not BP or absolute BP variability but rather its short-term erratic component, which has been previously shown to be an important prognostic marker for organ damage, cardiovascular, and all-cause mortality.

Motoric cognitive risk syndrome and mortality: results from the EPIDOS cohort.

BACKGROUND AND PURPOSE: Cognitive impairment, slow walking speed and motoric cognitive risk syndrome (MCR) have separately been associated with an increased risk for mortality in the short term. The aim of the study was to examine the association of MCR and its components [i.e. subjective cognitive complaint (SCC) and slow walking speed] with short-, medium- and long-term mortality in older community-dwellers. METHODS: In all, 3778 participants from the Epidémiologie de l'Ostéoporose (EPIDOS) study were selected. MCR was defined as the combination of slow walking speed and SCC in participants without major neurocognitive disorders. Deaths were prospectively recorded using mail, phone calls, questionnaires and/or the French national death registry at 5, 10, 15 and 19 (end of follow-up period) years. RESULTS: Over the follow-up of 19 years, 80.5% (n = 3043) participants died. Slow walking speed and MCR were associated with mortality [hazard ratio (HR) 1.20 with P = 0.004 for slow walking speed and HR = 1.26 with P = 0.002 for MCR at 10 years; HR = 1.27 with P ≤ 0.001 for slow walking speed and HR = 1.22 with P = 0.001 for MCR at 15 years; HR = 1.41 with P ≤ 0.001 at 19 years for slow walking speed and MCR]. There was no association between SCC and mortality. Kaplan-Meier distributions of mortality showed that participants with MCR and slow walking speed died earlier compared to healthy participants and those with SCC (P < 0.001). CONCLUSIONS: Slow walking speed and MCR were associated with an increased risk for mortality at the medium and long term, whereas no association was found with SCC.

Cognitive function in adolescence and the risk for premature diabetes and cardiovascular mortality in adulthood.

BACKGROUND: Epidemiological studies have demonstrated a relationship between cognitive function in youth and the future risk of death. Less is known regarding the relationship with diabetes related death. This study assessed the relationship between cognitive function in late adolescence and the risk for diabetes, cardiovascular- (CVD) and all-cause mortality in adulthood. METHODS: This retrospective study linked data from 2,277,188 16-19 year olds who had general intelligence tests (GIT) conducted during pre-military recruitment assessment with cause of death as coded by the Israel Central Bureau of Statistics. The associations between cognitive function and cause-specific mortality were assessed using Cox models. RESULTS: There were 31,268 deaths that were recorded during 41,916,603 person-years of follow-up, with a median follow-up of 19.2 (IQR 10.7, 29.5) years. 3068, 1443, 514 and 457 deaths were attributed to CVD, CHD, stroke, and diabetes, respectively. Individuals in the lowest GIT vs. highest GIT quintiles in unadjusted models had the highest risk for all-cause mortality (HR 1.84, 95% CI 1.78, 1.91), total CVD (HR 3.32, 95% CI 2.93, 3.75), CHD (HR 3.49 95% CI 2.92, 4.18), stroke (HR 3.96 95% CI 2.85, 5.5) and diabetes-related (HR 6.96 95% CI 4.68, 10.36) mortality. These HRs were attenuated following adjustment for age, sex, birth year, body-mass index, residential socioeconomic status, education and country of origin for all-cause (HR 1.23, 95% CI 1.17, 1.28), CVD (HR 1.76, 95% CI 1.52, 2.04), CHD (HR 1.7 95% CI 1.37, 2.11), stroke (HR 2.03, 95% CI 1.39, 2.98) and diabetes-related (HR 3.14 95% CI 2.00, 4.94) mortality. Results persisted in a sensitivity analyses limited to participants with unimpaired health at baseline and that accounted competing risk. CONCLUSIONS: This analysis of over 2 million demonstrates a strong relationship between cognitive function at youth and the risk for diabetes, all-cause and CVD-related mortality independent of adolescent obesity.

Understanding the relationship between cognition and death: a within cohort examination of cognitive measures and mortality.

Despite several studies demonstrating an independent and inverse association between cognition and mortality, the nature of this association still remains unclear. To examine the association of cognition and mortality after accounting for sociodemographic, health and lifestyle factors and to explore both test and population characteristics influencing this relationship. In a population based cohort of 8585 men and women aged 48-92 years, who had cognitive assessments in 2006-2011 and were followed up till 2016 for mortality, we examined the relationship between individual cognitive tests as well as a global cognition score to compare their ability in predicting mortality and whether these differed by population characteristics. Risk of death was estimated using Cox proportional hazard regression models including sociodemographic, lifestyle and health variables, and self-reported comorbidities, as covariates in the models. Poor cognitive performance (bottom quartile of combined cognition score) was associated with higher risk of mortality, Hazard Ratio = 1.32 (95% Confidence Interval 1.09, 1.60); individual cognitive tests varied in their mortality associations and also performed differently in middle-age and older age groups. Poor cognitive performance is independently associated with higher mortality. This association is observed for global cognition and for specific cognitive abilities. Associations vary depending on the cognitive test (and domain) as well as population characteristics, namely age and education.

Cancer and dementia: Two sides of the same coin?

Noncentral nervous system cancer and the brain share an interesting and complex relation, with an emerging body of evidence showing that cancer patients are at an increased risk of developing cognitive problems. In contrast, population-based studies consistently find an inverse link between cancer and dementia, that is patients with dementia having a lower risk of subsequently developing cancer, and cancer patients being less often diagnosed with dementia. Different biological processes such as inversely activated cell proliferation and survival pathways have been suggested to have an important role underlying this inverse association. However, the effect of methodological biases including surveillance or survival bias has not been completely ruled out, calling into question the inverse direction of the association between cancer and dementia. In fact, emerging evidence now suggests that cancer and dementia might share a positive association. This narrative review summarises the current literature on cancer, cognitive problems and dementia. Moreover, different strategies will be discussed to reduce the impact of potential methodological biases on the association between cancer and dementia, trying to reveal the true direction of this link.

Lower blood pressure during antihypertensive treatment is associated with higher all-cause mortality and accelerated cognitive decline in the oldest-old. Data from the Leiden 85-plus Study.

BACKGROUND: the appropriateness of lowering systolic blood pressure remains controversial in the oldest-old. We tested whether systolic blood pressure is associated with all-cause mortality and change in cognitive function for patients prescribed antihypertensive treatment and those without treatment. METHODS: we studied participants in the population-based Leiden 85-plus cohort study. Baseline systolic blood pressure and use of antihypertensive treatment were predictors; all-cause mortality and change in cognitive function measured using the Mini-Mental State Examination were the outcomes. Grip strength was measured as a proxy for physical frailty. We used Cox proportional hazards and mixed-effects linear regression models to analyse the relationship between systolic blood pressure and both time to death and change in cognitive function. In sensitivity analyses, we excluded deaths within 1 year and restricted analyses to participants without a history of cardiovascular disease. RESULTS: of 570 participants, 249 (44%) were prescribed antihypertensive therapy. All-cause mortality was higher in participants with lower blood pressure prescribed antihypertensive treatment (HR 1.29 per 10 mmHg lower systolic blood pressure, 95% CI 1.15-1.46, P < 0.001). Participants taking antihypertensives showed an association between accelerated cognitive decline and lower blood pressure (annual mean change -0.35 points per 10 mmHg lower systolic blood pressure, 95% CI -0.60, -0.11, P = 0.004); decline in cognition was more rapid in those with lower hand grip strength. In participants not prescribed antihypertensive treatment, no significant associations were seen between blood pressure and either mortality or cognitive decline. CONCLUSIONS: lower systolic blood pressure in the oldest-old taking antihypertensives was associated with higher mortality and faster decline in cognitive function.

Impaired cognition is associated with adverse outcome in older patients in the Emergency Department; the Acutely Presenting Older Patients (APOP) study.

Objective: to investigate whether cognitive impairment, measured early after Emergency Department (ED) arrival and irrespective of its cause, is independently associated with functional decline or mortality after 3 and 12 months in older ED patients. Design and setting: a prospective multi-centre cohort study in all Acutely Presenting Older Patients visiting the Emergency Department (APOP study) of three hospitals in the Netherlands. Participants: 2,130 patients, ≥70 years. Measurements: data on demographics, disease severity and geriatric characteristics were collected during the first hour of the ED visit. Cognition was measured using the 6-Item-Cognitive-Impairment-Test ('6CIT'). Cognitive impairment was defined as 6CIT ≥11, self-reported dementia or the inability to perform the cognition test. The composite adverse outcome after 3 and 12 months was defined as a 1-point decrease in Katz Activities of Daily Living (ADL), new institutionalisation or mortality. Multivariable regression analysis was used to assess whether cognitive impairment independently associates with adverse outcome. Results: of 2,130 included patients, 588 (27.6%) had cognitive impairment at baseline and 654 patients (30.7%) suffered from adverse outcome after 3 months. Cognitive impairment associated with increased risk for adverse outcome (adjusted odds ratio (OR) 1.72, 95%CI 1.37-2.17). After 12 months, 787 patients (36.9%) suffered from adverse outcome. Again, cognitive impairment independently associated with increased risk for adverse outcome (adjusted OR 1.89, 95%CI 1.46-2.46). ORs were similar for patients who were discharged home versus hospitalised patients. Conclusion: cognitive impairment measured during the early stages of ED visit, irrespective of the cause, is independently associated with adverse outcome after 3 and 12 months in older patients.

Postoperative cognitive dysfunction and mortality following lung transplantation.

Preliminary evidence suggests that postoperative cognitive dysfunction (POCD) is common after lung transplantation. The impact of POCD on clinical outcomes has yet to be studied. The association between POCD and longer-term survival was therefore examined in a pilot study of posttransplantation survivors. Forty-nine participants from a prior randomized clinical trial underwent a neurocognitive assessment battery pretransplantation and 6 months posttransplantation, including assessments of the domains of Executive Function (Trail Making Test, Stroop, Digit Span), Processing Speed (Ruff 2 and 7 Test, Digit Symbol Substitution Test), and Verbal Memory (Verbal Paired Associates, Logical Memory, Animal Naming, and Controlled Oral Word Association Test). During a 13-year follow-up, 33 (67%) participants died. Greater neurocognition was associated with longer survival (hazard ratio [HR] = 0.49 [0.25-0.96], P = .039), and this association was strongest on tests assessing Processing Speed (HR = 0.58 [0.36-0.95], P = .03) and Executive Function (HR = 0.52 [0.28-0.97], P = .040). In addition, unadjusted analyses suggested an association between greater Memory performance and lower risk of CLAD (HR = 0.54 [0.29-1.00], P = .050). Declines in Executive Function tended to be predictive of worse survival. These preliminary findings suggest that postoperative neurocognition is predictive of subsequent mortality among lung transplant recipients. Further research is needed to confirm these findings in a larger sample and to examine mechanisms responsible for this relationship.

Joint modelling of longitudinal 3MS scores and the risk of mortality among cognitively impaired individuals.

BACKGROUND: Modified Mini-Mental State Examination (3MS) is an instrument administered by trained personnel to examine levels of participants' cognitive function. However, the association between changes in scores over time and the risk of death (mortality) is not known. The aims of this study are to examine the association between 3MS scores and mortality via cognitive impairment among older women and to determine individuals' risk of changes in scores to better predict their survival and mortality rates. METHODS: We propose a Bayesian joint modelling approach to determine mortality due to cognitive impairment via repeated measures of 3MS scores trajectories over a 21-year follow-up period. Data for this study are taken from the Osteoporotic Fracture longitudinal study among women aged 65+ which started in 1986-88. RESULTS: The standard relative risk model from the analyses with a baseline 3MS score after adjusting for all the significant covariates demonstrates that, every unit decrease in a 3MS score corresponds to a non-significant 1.059 increase risk of mortality with a 95% CI of (0.981, 1.143), while the extended model results in a significant 0.09% increased risk in mortality. The joint modelling approach found a strong association between the 3MS scores and the risk of mortality, such that, every unit decrease in 3MS scores results in a 1.135 (13%) increased risk of death via cognitive impairment with a 95% CI of (1.056, 1.215). CONCLUSION: It has been demonstrated that a decrease in 3MS results has a significant increase risk of mortality due to cognitive impairment via joint modelling, but insignificant when considered under the standard relative risk approach.

Synergistic effects of cognitive impairment on physical disability in all-cause mortality among men aged 80 years and over: Results from longitudinal older veterans study.

OBJECTIVE: We evaluated effects of the interrelationship between physical disability and cognitive impairment on long-term mortality of men aged 80 years and older living in a retirement community in Taiwan. METHODS: This prospective cohort study enrolled older men aged 80 and older living in a Veterans Care Home. Those with confirmed diagnosis of dementia were excluded. All participants received comprehensive geriatric assessment, including sociodemographic data, Charlson's Comorbidity Index (CCI), geriatric syndromes, activities of daily living (ADL) using the Barthel index and cognitive function using the Mini-Mental State Examination (MMSE). Subjects were categorized into normal cognitive function, mild cognitive deterioration, and moderate-to-severe cognitive impairment and were further stratified by physical disability status. Kaplan-Meier log-rank test was used for survival analysis. After adjusting for sociodemographic characteristics and geriatric syndromes, Cox proportional hazards model was constructed to examine associations between cognitive function, disability and increased mortality risk. RESULTS: Among 305 male subjects aged 85.1 ± 4.1 years, 89 subjects died during follow-up (mean follow-up: 1.87 ± 0.90 years). Kaplan-Meier unadjusted analysis showed reduced survival probability associated with moderate-to-severe cognitive status and physical disability. Mortality risk increased significantly only for physically disabled subjects with simultaneous mild cognitive deterioration (adjusted HR 1.951, 95% CI 1.036-3.673, p = 0.038) or moderate-to-severe cognitive impairment (aHR 2.722, 95% CI 1.430-5.181, p = 0.002) after adjusting for age, BMI, education levels, smoking status, polypharmacy, visual and hearing impairment, urinary incontinence, fall history, depressive symptoms and CCI. Mortality risk was not increased among physically independent subjects with or without cognitive impairment, and physically disabled subjects with intact cognition. CONCLUSIONS: Physical disability is a major risk factor for all-cause mortality among men aged 80 years and older, and risk increased synergistically when cognitive impairment was present. Cognitive impairment alone without physical disability did not increase mortality risk in this population.

Effect of the treatment of Type 2 diabetes mellitus on the development of cognitive impairment and dementia.

BACKGROUND: Prevention of cognitive impairment and dementia is an important public health goal. Epidemiological evidence shows a relationship between cognitive impairment and Type 2 diabetes mellitus. The risk of dementia increases with duration of disease. This updated systematic review investigated the effect on cognitive function of the type of treatment and level of metabolic control in people with Type 2 diabetes. OBJECTIVES: To assess the effects of different strategies for managing Type 2 diabetes mellitus on cognitive function and the incidence of dementia. SEARCH METHODS: We searched ALOIS (the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group (CDCIG)), the Cochrane Library, MEDLINE, Embase, PsycINFO, CINAHL and LILACS on 15 October 2016. ALOIS contains records from all major health care databases, (CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL, LILACS), as well as from many trials' registers and grey literature sources. SELECTION CRITERIA: We included randomised controlled trials (RCTs) which compared two or more different treatments for Type 2 diabetes mellitus and in which cognitive function was measured at baseline and after treatment. DATA COLLECTION AND ANALYSIS: Two review authors independently extracted data and assessed the quality of the included RCTs. We pooled data for comparable trials and estimated the effects of treatment by using risk ratios (RRs) and mean differences (MDs), according to the nature of the outcome. We assessed the quality of the evidence using GRADE methods. MAIN RESULTS: We identified seven eligible studies but only four provided data we could include in efficacy analyses. Two of these studies compared intensive versus standard glycaemic control and two compared different pharmacological treatments. All studies were at unclear risk of bias in at least two domains and one large study was at high risk of performance and detection bias.(a) Two studies with 13,934 participants at high cardiovascular risk provided efficacy data on intensive versus standard glycaemic control. A third study with 1791 participants provided additional data on hypoglycaemic episodes and mortality. There is probably no difference between treatment groups in the number of participants who decline by at least 3 points on the Mini-Mental State Examination (MMSE) over five years (RR 0.98, 95% CI 0.88 to 1.08; 1 study; n = 11,140; moderate-quality evidence); and there may also be little or no difference in the incidence of dementia (RR 1.27, 95% CI 0.87 to 1.85; 1 study; n = 11,140; low-quality evidence). From another study, there was probably little or no difference in MMSE score after 40 months (MD -0.01, 95% CI -0.18 to 0.16; 1 study; n = 2794; moderate quality evidence). Participants exposed to the intensive glycaemic control strategy probably experience more episodes of severe hypoglycaemia than those who have standard treatment (RR 2.18, 95% CI 1.52 to 3.14; 2 studies; n = 12,827; moderate-quality evidence). The evidence from these trials suggests that the intensity of glycaemic control may have little or no effect on all-cause mortality (RR 0.99, 95% CI 0.87 to 1.13; 3 studies; n = 15,888; low-quality evidence).(b) One study with 156 participants compared glibenclamide (glyburide) with repaglinide. There may be a small advantage of glibenclamide on global cognitive function measured with the MMSE after 12 months (MD -0.90, 95% CI -1.68 to -0.12; low-quality evidence). No data were reported on the incidence of dementia, hypoglycaemic events or all-cause mortality.(c) One study with 145 participants compared rosiglitazone plus metformin to glibenclamide (glyburide) plus metformin over 24 weeks. It reported only on cognitive subdomains and not on global cognitive function, incidence of MCI or dementia, hypoglycaemic events or all causes of mortality. AUTHORS' CONCLUSIONS: We found no good evidence that any specific treatment or treatment strategy for Type 2 diabetes can prevent or delay cognitive impairment. The best available evidence related to the comparison of intensive with standard glycaemic control strategies. Here there was moderate-quality evidence that the strategies do not differ in their effect on global cognitive functioning over 40 to 60 months.

Optimising care for patients with cognitive impairment and dementia following hip fracture.

The global shift in demographics towards aging populations is leading to a commensurate increase in age-related disease and frailty. It is essential to optimise health services to meet current needs and prepare for anticipated future demands. This paper explores issues impacting on people living with cognitive impairment and/or dementia who experience a hip fracture and are cared for in acute settings. This is important given the high mortality and morbidity associated with this population. Given the current insufficiency of clear evidence on optimum rehabilitation of this patient group, this paper explored three key themes namely: recognition of cognitive impairment, response by way of training and education of staff to optimise care for this patient group and review of the importance of outcomes measures. Whilst there is currently insufficient evidence to draw conclusions about the optimal ways of caring for patients living with dementia following hip fracture, this paper concludes that future research should improve understanding of healthcare staff education to improve the outcomes for this important group of patients.

The relationship between cognitive impairment, mortality and discharge characteristics in a large cohort of older adults with unscheduled admissions to an acute hospital: a retrospective observational study.

Background: older people with dementia admitted to hospital for acute illness have higher mortality and longer hospital stays compared to those without dementia. Cognitive impairment (CI) is common in older people, and they may also be at increased risk of poor outcomes. Methods: retrospective observational study of unscheduled admissions aged ≥75 years. Admission characteristics, mortality rates and discharge outcomes were compared between three groups: (i) known dementia diagnosis (DD), (ii) CI but no diagnosis of dementia and (iii) no CI. Results: of 19,269 admissions (13,652 patients), 19.8% had a DD, 11.6% had CI and 68.6% had neither. Admissions with CI or DD were older and had more females than those with no CI, and were more likely to be admitted through the Emergency Department (88.4% and 90.7%, versus 82.0%) and to medical wards (89.4% and 84.4%, versus 76.8%). Acuity levels at admission were similar between the groups. Patients with CI or DD had more admissions at 'high risk' from malnutrition than patients with no CI (28.0% and 33.7% versus 17.5%), and a higher risk of dying in hospital (11.8% [10.5-13.3] and 10.8% [9.8-11.9] versus (6.6% [6.2-7.0])). Conclusions: the admission characteristics, mortality and length of stay of patients with CI resemble those of patients with diagnosed dementia. Whilst attention has been focussed on the need for additional support for people with dementia, patients with CI, which may include those with undiagnosed dementia or delirium, appear to have equally bad outcomes from hospitalisation.