Predicting Patient Deterioration: A Review of Tools in the Digital Hospital Setting.

BACKGROUND: Early warning tools identify patients at risk of deterioration in hospitals. Electronic medical records in hospitals offer real-time data and the opportunity to automate early warning tools and provide real-time, dynamic risk estimates. OBJECTIVE: This review describes published studies on the development, validation, and implementation of tools for predicting patient deterioration in general wards in hospitals. METHODS: An electronic database search of peer reviewed journal papers from 2008-2020 identified studies reporting the use of tools and algorithms for predicting patient deterioration, defined by unplanned transfer to the intensive care unit, cardiac arrest, or death. Studies conducted solely in intensive care units, emergency departments, or single diagnosis patient groups were excluded. RESULTS: A total of 46 publications were eligible for inclusion. These publications were heterogeneous in design, setting, and outcome measures. Most studies were retrospective studies using cohort data to develop, validate, or statistically evaluate prediction tools. The tools consisted of early warning, screening, or scoring systems based on physiologic data, as well as more complex algorithms developed to better represent real-time data, deal with complexities of longitudinal data, and warn of deterioration risk earlier. Only a few studies detailed the results of the implementation of deterioration warning tools. CONCLUSIONS: Despite relative progress in the development of algorithms to predict patient deterioration, the literature has not shown that the deployment or implementation of such algorithms is reproducibly associated with improvements in patient outcomes. Further work is needed to realize the potential of automated predictions and update dynamic risk estimates as part of an operational early warning system for inpatient deterioration.

The Effects of Telemonitoring on Patient Compliance With Self-Management Recommendations and Outcomes of the Innovative Telemonitoring Enhanced Care Program for Chronic Heart Failure: Randomized Controlled Trial.

BACKGROUND: Telemonitoring enables care providers to remotely support outpatients in self-managing chronic heart failure (CHF), but the objective assessment of patient compliance with self-management recommendations has seldom been studied. OBJECTIVE: This study aimed to evaluate patient compliance with self-management recommendations of an innovative telemonitoring enhanced care program for CHF (ITEC-CHF). METHODS: We conducted a multicenter randomized controlled trial with a 6-month follow-up. The ITEC-CHF program comprised the provision of Bluetooth-enabled scales linked to a call center and nurse care services to assist participants with weight monitoring compliance. Compliance was defined a priori as weighing at least 4 days per week, analyzed objectively from weight recordings on the scales. The intention-to-treat principle was used to perform the analysis. RESULTS: A total of 184 participants (141/184, 76.6% male), with a mean age of 70.1 (SD 12.3) years, were randomized to receive either ITEC-CHF (n=91) or usual care (control; n=93), of which 67 ITEC-CHF and 81 control participants completed the intervention. For the compliance criterion of weighing at least 4 days per week, the proportion of compliant participants in the ITEC-CHF group was not significantly higher than that in the control group (ITEC-CHF: 67/91, 74% vs control: 56/91, 60%; P=.06). However, the proportion of ITEC-CHF participants achieving the stricter compliance standard of at least 6 days a week was significantly higher than that in the control group (ITEC-CHF: 41/91, 45% vs control: 23/93, 25%; P=.005). CONCLUSIONS: ITEC-CHF improved participant compliance with weight monitoring, although the withdrawal rate was high. Telemonitoring is a promising method for supporting both patients and clinicians in the management of CHF. However, further refinements are required to optimize this model of care. TRIAL REGISTRATION: Australian New Zealand Clinical Trial Registry ACTRN12614000916640; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=366691.

Immunisation status of children presenting to the emergency department: Linkage of a longitudinal birth cohort with national immunisation data.

AIM: To describe the relationship between emergency department (ED) diagnosis of infectious disease and immunisation status in children ≤5 years. We also aimed to demonstrate feasibility of proof-of-concept linkage between disparate databases. METHODS: Data from a cohort of 3404 children born in Southeast Queensland/Far North New South Wales between 2006 and 2011 were linked to Australian Childhood Immunisation Registry data and Emergency Department Information System data for presentations between 2006 and 2014. Immunisation status was assigned using the 2009 National Immunisation Program schedule. RESULTS: Of 1490 children (79% of those consented) with data on immunisation status, 87.2 and 84.6% were fully immunised by 12 and 24 months, respectively. Adding partially immunised children increased this to 93.2 and 91.4% at 12 and 24 months, respectively. Nearly two-thirds of all children made at least one ED presentation. Children presenting to ED with an infectious disease did not differ in immunisation status compared to children with other (non-infectious disease type) presentations but were younger, more likely to live with other children and had a longer ED stay and higher admission rate. Respiratory syncytial virus (RSV) was more frequently diagnosed in unimmunised children. CONCLUSIONS: In an existing birth cohort, immunisation rates were lower than the national average. RSV was more prevalent in unimmunised children presenting to ED, but immunisation status was not significantly associated with other infectious disease presentations. Linkage between national immunisation data and Australian ED data is feasible and has the potential to identify previously unrecognised factors related to child immunisation status and health-care utilisation.

Parental-reported allergic disorders and emergency department presentations for allergy in the first five years of life; a longitudinal birth cohort.

BACKGROUND: To measure rates of parental-report of allergic disorders and ED presentations for allergic disorders in children, and to describe factors associated with either. METHODS: An existing cohort of 3404 children born between 2006 and 2011 (Environments for Healthy Living) with prospectively collected pre-natal, perinatal and follow-up data were linked to i) nationwide Medicare and pharmaceutical data and ii) Emergency Department (ED) data from four hospitals in Australia. Parental-reported allergy was assessed in those who returned follow-up questionnaires. ED presentation was defined as any presentation for a suite of allergic disorders, excluding asthma. Univariate analysis and multivariate logistic regression were used to descibe risk factors for both parental-reported allergy and ED presentation for an allergic disorder. RESULTS: The incidence of parental-reported child allergy at 1, 3 and 5 years of age was 7.8, 7.8 and 12.6%, respectively. Independent predictors of parental-report of allergy in multivariate analysis were parental-report of asthma (OR 2.2, 95% CI 1.4-3.4) or eczema (OR 4.3, 95% CI 3.1-6.1) and age > 6 months at introduction of solids (OR 1.3, 95% CI 1.0-1.7). Factors associated with ED presentations for allergy, which occurred in 3.6% of the cohort, were presence of maternal asthma (OR 2.3 95% CI:1.1, 4.9) and child born in spring (OR 1.7, 95% CI 1.1, 2.7). CONCLUSIONS: More than 10% of children up to 5 years have a parental-reported allergic disorder, and 3.6% presented to ED. Parental-report of eczema and/or asthma and late introduction of solids were predictors of parental-report of allergy. Spring birth and maternal asthma were predictors for ED presentation for allergy.

Emergency department presentations in infants: Predictors from an Australian birth cohort.

AIM: Infants under 12 months of age are disproportionately represented amongst emergency department (ED) presentations, and infants are more likely to be frequent ED users. This study aimed to describe and identify psychosocial predictors of ED presentation in infants. METHODS: A prospective birth cohort from Queensland and New South Wales (Environments for Healthy Living) was used to understand infant health service use. Baseline and 12-month questionnaire data pertaining to children born between 2006 and 2011 were used to identify predictors of ED presentation, using multiple regression analysis. RESULTS: Of the 2184 children in the cohort with available baseline and 12-month data, 579 (27%) presented at least once to an ED during their first 12 months of life. Statistically significant predictors of ED presentation in the multivariate analysis included the mother having asthma (odds ratio (OR) 1.67, 95% confidence interval (CI) 1.15-2.39) and a higher Kessler-6 score (a measure of psychological distress) of the primary carer at baseline (OR 1.04, 95% CI 1.01-1.08). Maternal education level was not associated with ED presentations of infants. CONCLUSIONS: This study describes maternal and child factors of children who present to the ED in the first year of life. Factors related to an infant's support system were found to be predictors for an ED presentation in the first year of life. This study emphasises the need to review the maternal medical history and psychosocial situation. There may be benefits for health-care practitioners to take the opportunity (such as during routine childhood immunisation) to perform a brief screening tool (such as the Kessler-6) to understand psychological distress experienced by mothers. This may influence the likelihood of a child presenting to an ED within the first 12 months of life.

The National Emergency Access Target (NEAT) and the 4-hour rule: time to review the target.

OBJECTIVE: We explored the relationship between the National Emergency Access Target (NEAT) compliance rate, defined as the proportion of patients admitted or discharged from emergency departments (EDs) within 4 hours of presentation, and the risk-adjusted in-hospital mortality of patients admitted to hospital acutely from EDs. DESIGN, SETTING AND PARTICIPANTS: Retrospective observational study of all de-identified episodes of care involving patients who presented acutely to the EDs of 59 Australian hospitals between 1 July 2010 and 30 June 2014. MAIN OUTCOME MEASURE: The relationship between the risk-adjusted mortality of inpatients admitted acutely from EDs (the emergency hospital standardised mortality ratio [eHSMR]: the ratio of the numbers of observed to expected deaths) and NEAT compliance rates for all presenting patients (total NEAT) and admitted patients (admitted NEAT). RESULTS: ED and inpatient data were aggregated for 12.5 million ED episodes of care and 11.6 million inpatient episodes of care. A highly significant (P < 0.001) linear, inverse relationship between eHSMR and each of total and admitted NEAT compliance rates was found; eHSMR declined to a nadir of 73 as total and admitted NEAT compliance rates rose to about 83% and 65% respectively. Sensitivity analyses found no confounding by the inclusion of palliative care and/or short-stay patients. CONCLUSION: As NEAT compliance rates increased, in-hospital mortality of emergency admissions declined, although this direct inverse relationship is lost once total and admitted NEAT compliance rates exceed certain levels. This inverse association between NEAT compliance rates and in-hospital mortality should be considered when formulating targets for access to emergency care.

A prediction model for colon cancer surveillance data.

Dynamic prediction models make use of patient-specific longitudinal data to update individualized survival probability predictions based on current and past information. Colonoscopy (COL) and fecal occult blood test (FOBT) results were collected from two Australian surveillance studies on individuals characterized as high-risk based on a personal or family history of colorectal cancer. Motivated by a Poisson process, this paper proposes a generalized nonlinear model with a complementary log-log link as a dynamic prediction tool that produces individualized probabilities for the risk of developing advanced adenoma or colorectal cancer (AAC). This model allows predicted risk to depend on a patient's baseline characteristics and time-dependent covariates. Information on the dates and results of COLs and FOBTs were incorporated using time-dependent covariates that contributed to patient risk of AAC for a specified period following the test result. These covariates serve to update a person's risk as additional COL, and FOBT test information becomes available. Model selection was conducted systematically through the comparison of Akaike information criterion. Goodness-of-fit was assessed with the use of calibration plots to compare the predicted probability of event occurrence with the proportion of events observed. Abnormal COL results were found to significantly increase risk of AAC for 1 year following the test. Positive FOBTs were found to significantly increase the risk of AAC for 3 months following the result. The covariates that incorporated the updated test results were of greater significance and had a larger effect on risk than the baseline variables.

Ideal colonoscopic surveillance intervals to reduce incidence of advanced adenoma and colorectal cancer.

BACKGROUND AND AIMS: There is limited information about the interplay between multiple risk factors contributing to the risk of advanced neoplasia. We determined the actual risk for advanced neoplasia in relation to lapsed time between colonoscopies in people enrolled in a structured surveillance program. This risk information can be used to guide the selection of optimal surveillance intervals. METHODS: Patients were recruited into programs at two major tertiary hospitals, with a personal or family history of advanced neoplasia. Five thousand one hundred forty-one patients had an index and one or more surveillance colonoscopies. Fifty-one percent had a family history of colorectal neoplasia while the remainder had a personal history. RESULTS: Patients with an immediately prior colonoscopy result (prior result) of advanced adenoma had a risk for advanced neoplasia 7.1 times greater than those with a normal prior result. Cancer as a prior result did not confer a greater risk than either a hyperplastic polyp or a nonadvanced adenoma. Being female reduced risk, age increased risk. Only a family history of a first-degree relative diagnosed under 55, or definite or suspected hereditary nonpolyposis colorectal cancer (HNPCC) conferred an increased risk over a personal history of advanced neoplasia. CONCLUSIONS: Most family history categories did not confer excess risk above personal history of advanced neoplasia. A prior cancer poses less of a risk than a prior advanced adenoma. Based on our models, a person with an advanced adenoma should be scheduled for colonoscopy at 3 years, corresponding to a 15% risk of advanced neoplasia for a male aged under 56. Guidelines should be updated that uses a 15% risk as a benchmark for calculating surveillance intervals.

A state wide validation and utilisation study of the Queensland emergency nursing workforce tool.

AIM: To describe and compare standard practice with a revised, assisted method for calculating emergency department nursing workforce requirements (using the emergency nursing workforce tool, ENWT) within 27 Queensland public hospital emergency departments (ED). BACKGROUND: Despite the presence of several methodologies used for staffing calculations, there is a necessity to refine measures of emergency department complexity and workload to determine appropriate staffing in order to meet patient safety needs and health service key priority indicators. METHODS: A descriptive comparative study design was employed. Of the 27 ED nurse unit managers (NUM) invited, 18 (67%) participated. RESULTS: No significant difference was noted in the full time equivalent (FTE) nursing requirement when standard vs. new (ENWT) methods were compared. The ENWT was more efficient (i.e. timely) and had better predictability than existing methods for calculating FTE nursing requirement. CONCLUSION: The methodology underpinning the ENWT may be useful to apply or adapt to settings other than the ED (e.g. intensive care, operating room) and disciplines within the ED other than nursing (e.g. medicine, allied health, porterage) to inform staffing requirements. IMPLICATIONS FOR NURSING MANAGEMENT: Findings from this research can be used to inform ED managers and health service planners regarding a standardized approach to calculating emergency nursing workforce needs.

Graphical Association Analysis for Identifying Variation in Provider Claims for Joint Replacement Surgery.

Identifying potentially fraudulent or wasteful medical insurance claims can be difficult due to the large amounts of data and human effort involved. We applied unsupervised machine learning to construct interpretable models which rank variations in medical provider claiming behaviour in the domain of unilateral joint replacement surgery, using data from the Australian Medicare Benefits Schedule. For each of three surgical procedures reference models of claims for each procedure were constructed and compared analytically to models of individual provider claims. Providers were ranked using a score based on fees for typical claims made in addition to those in the reference model. Evaluation of the results indicated that the top-ranked providers were likely to be unusual in their claiming patterns, with typical claims from outlying providers adding up to 192% to the cost of a procedure. The method is efficient, generalizable to other procedures and, being interpretable, integrates well into existing workflows.

Leveraging existing data to improve antimicrobial resistance-related mortality estimates for Australia.

Antimicrobial resistance (AMR) is a global pandemic, however, estimating its burden is a complex process. As a result, many countries rely on global estimates to infer burden within their own setting. With a growing number of recent publications quantifying AMR burden in Australia, and an expansion of surveillance programs, enumerating AMR mortality for Australia is feasible. We aimed to leverage existing published data to assess methodological factors contributing to the considerable variation in AMR-related mortality and provide two reliable estimates of AMR mortality in Australia. This is a necessary step towards generating meaningful measures of AMR burden in Australia.

Readmission Risk Based on Debility and Psychosocial Measures: The Western 9 Algorithm.

Many studies have stressed the importance of psychosocial determinants of health such as food insecurity, housing instability, and education level, as important drivers of health outcomes. Western Health developed a set of nine screening questions (the Western 9) based on psychosocial measures to profile patients enrolled in the HealthLinks Chronic Care initiative. An aggregate score was then converted into a Low, Medium and High risk profiles. The aim of the study was to see if the Western 9 questions added additional discriminative power to existing risk of readmission algorithms. Results show that the inclusion of the risk profiles significantly improved model fit and calibration compared to a baseline risk model. Suggestions for further refinement include developing weighted indices for the Western 9 to improve model fit.

Mortality and readmission differences associated with after-hours hospital admission: A population-based cohort study in Queensland Australia.

Background and Aims: Policy makers and health system managers are seeking evidence on the risks involved for patients associated with after-hours care. This study of approximately 1 million patients who were admitted to the 25 largest public hospitals in Queensland Australia sought to quantify mortality and readmission differences associated with after-hours hospital admission. Methods: Logistic regression was used to assess whether there were any differences in mortality and readmissions based on the time inpatients were admitted to hospital (after-hours versus within hours). Patient and staffing data, including the variation in physician and nursing staff numbers and seniority were included as explicit predictors within patient outcome models. Results: After adjusting for case-mix confounding, statistically significant higher mortality was observed for patients admitted on weekends via the hospital's emergency department compared to within hours. This finding of elevated mortality risk after-hours held true in sensitivity analyses which explored broader definitions of after-hours care: an "Extended" definition comprising a weekend extending into Friday night and early Monday morning; and a "Twilight" definition comprising weekends and weeknights.There were no significant differences in 30-day readmissions for emergency or elective patients admitted after-hours. Increased mortality risks for elective patients was found to be an evening/weekend effect rather than a day-of-week effect. Workforce metrics that played a role in observed outcome differences within hours/after-hours were more a time of day rather than day of week effect, i.e. staffing impacts differ more between day and night than the weekday versus weekend. Conclusion: Patients admitted after-hours have significantly higher mortality than patients admitted within hours. This study confirms an association between mortality differences and the time patients were admitted to hospital, and identifies characteristics of patients and staffing that affect those outcomes.

Early discharge and its effect on ED length of stay and access block.

Effecting early discharge is a widely recommended strategy for improving patient flow in acute hospitals. This paper analyses the impact of inpatient discharge timing on Emergency Department (ED) flow parameters such as access block and length of stay, while comparing this to the effect on hospital occupancy, to arrive at an understanding of a 'whole of hospital' response to discharge timing. The impact of hospital size is also investigated. The analysis reveals that, on days when the discharge peak lags the peak in inpatient admissions, hospitals of all sizes exhibit increased levels of occupancy, inpatient and ED length of stay, and access block. The findings corroborate the efficacy of early discharge initiatives and 'whole of hospital' flow improvement initiatives for addressing overcrowding and efficiency issues in hospitals.

Explainable machine learning for real-time deterioration alert prediction to guide pre-emptive treatment.

The Electronic Medical Record (EMR) provides an opportunity to manage patient care efficiently and accurately. This includes clinical decision support tools for the timely identification of adverse events or acute illnesses preceded by deterioration. This paper presents a machine learning-driven tool developed using real-time EMR data for identifying patients at high risk of reaching critical conditions that may demand immediate interventions. This tool provides a pre-emptive solution that can help busy clinicians to prioritize their efforts while evaluating the individual patient risk of deterioration. The tool also provides visualized explanation of the main contributing factors to its decisions, which can guide the choice of intervention. When applied to a test cohort of 18,648 patient records, the tool achieved 100% sensitivity for prediction windows 2-8 h in advance for patients that were identified at 95%, 85% and 70% risk of deterioration.

Interval fecal immunochemical testing in a colonoscopic surveillance program speeds detection of colorectal neoplasia.

BACKGROUND & AIMS: Rapidly progressing or missed lesions can reduce the effectiveness of colonoscopy-based colorectal cancer surveillance programs. We investigated whether giving fecal immunochemical tests (FITs) for hemoglobin between surveillance colonoscopies resulted in earlier detection of neoplasia. METHODS: The study included 1736 patients with a family history or past neoplasia; they received at least 2 colonoscopy examinations and were followed for a total of 8863 years. Patients were excluded from the study if they had genetic syndromes, colorectal surgery, or inflammatory bowel disease. An FIT was offered yearly, in the interval between colonoscopies; if results were positive, the colonoscopy was performed earlier than scheduled. RESULTS: Among the 1071 asymptomatic subjects (61%) who received at least 1 FIT, the test detected 12 of 14 cancers (86% sensitivity) and 60 of 96 (63%) advanced adenomas. In patients with positive results from the FIT, the diagnosis of cancer was made 25 months (median) earlier and diagnosis of advanced adenoma 24 months earlier. Patients who had repeated negative results from FIT had an almost 2-fold decrease in risk for cancer and advanced adenoma compared with patients who were not tested (5.5% vs 10.1%, respectively, P = .0004). The most advanced stages of neoplasia, observed across the continuum from nonadvanced adenoma to late-stage cancer, were associated with age (increased with age), sex (increased in males), and FIT result. The probability of most advanced neoplastic stage was lowest among those with a negative result from the FIT (odds ratio, 0.68; P < .001). CONCLUSIONS: Interval examinations using the FIT detected neoplasias sooner than scheduled surveillances. Subjects with negative results from the FIT had the lowest risk for the most advanced stage of neoplasia. Interval FIT analyses can be used to detect missed or rapidly developing lesions in surveillance programs.

A web-based normative data tool for assessing cognitive performance in healthy older Australians.

A decline in cognition greater than expected with ageing and accompanied by subjective cognitive concerns or functional changes may be indicative of a dementing disorder. The capacity to correctly identify cognitive decline relies on comparisons with normative data from a suitably matched healthy reference group with relatively homogeneous demographic features. Formal assessment of cognition is usually performed by specialist neuropsychologists trained in administration and interpretation of psychometric tests. With a scarcity of normative data from large cohorts of older adults, Australian neuropsychologists commonly use representative data from small international studies. Data from 727 healthy older Australians participating in the Australian Imaging, Biomarkers and Lifestyle (AIBL) Flagship Study of Ageing have been used to create a normative dataset. A web-based calculator was developed to simplify the time-consuming process of comparing cognitive performance scores with these representative data.

Impact of admission and discharge peak times on hospital overcrowding.

The ability of hospital staff to get a patient to the right bed at the right time is dependent on bed occupancy, and is a key issue in all acute hospitals. This paper seeks to identify the impact of admission and discharge timing on hospital occupancy with reference to the peak in daily admissions and discharges. Patient admissions data from 23 Queensland public hospitals was classified into categories based on the relative timing of daily admission and discharge curves. We found statistically significant differences in mean and peak occupancy and patient length of stay between categories (one-way univariate ANOVA p<0.0001). The results support early patient discharge initiatives to reduce hospital occupancy rates.

After-hours emergency department care: Does time or day of arrival affect survival?

OBJECTIVE: To determine whether after-hours presentation to EDs is associated with differences in 7-day and 30-day mortality. The influence of patient case-mix and workforce staffing differences are also explored. METHODS: We conducted a retrospective observational study of 3.7 million ED episodes across 30 public hospitals in Queensland, Australia during May 2013-September 2015 using routinely collected hospital data linked to hospital staffing data and the death registry. Episodes were categorised as within/after-hours using time of presentation. Staffing was derived from payroll records and explored by defining 11 staffing ratios. RESULTS: Weekend presentation was slightly more associated (7-day mortality odds ratio 1.05, 95% confidence interval [CI] 1.01-1.10) or no more associated (30-day mortality odds ratio 1.01, 95% CI 0.98-1.03) with death than weekday presentation. When weeknights are included in the 'after-hours' period, odds ratios are smaller, so that after-hours presentation is no more associated (7-day mortality odds ratio 1.03, 95% CI 0.99-1.08) or less associated (30-day mortality odds ratio 0.95, 95% CI 0.93-0.97) with death. No significant after-hours patient case-mix differences were observed between weekday and weekend presentations for 7-day mortality. In other combinations of outcome and after-hours definition, some differences (especially measures relating to severity of presenting condition) were found. Staffing ratios were not strongly associated with any within/after-hours differences in ED mortality. CONCLUSIONS: After-hours presentation on the weekend to an ED is associated with higher 7-day mortality even after controlling for case-mix.

Structure-activity relationship of butyrate analogues on apoptosis, proliferation and histone deacetylase activity in HCT-116 human colorectal cancer cells.

1. Butyrate, a bacteria fermentative product in the colonic lumen, has been shown to produce a wide variety of biological effects in human cancer cells in vitro. However, there are pharmacological drawbacks associated with the use of butyrate therapy and there are limited published data on the structure-activity relationship of butyrate analogues in colorectal cancer cells. Previously, we determined structure-activity relationship using HT-29 human colorectal cancer cells. However, it was viewed as important to explore similar relationships in another colorectal cancer cell line. 2. Therefore, in the present study, the in vitro structure-activity relationship of butyrate analogues was examined by investigating their effects on apoptosis, cell proliferation, histone deacetylase (HDAC) activity and lactate dehydrogenase (LDH) leakage as a measure of cell toxicity in HCT-116 human colorectal cancer cells. 3. Of the 32 analogues tested, only 4-benzoylbutyrate, 3-benzo-ylpropionate, 4-(4-nitrophenyl)butyrate and 3-(4-fluorobenzoyl)propionate exhibited comparable biological effects to butyrate. The common structural properties of the compounds of interest were to lack amino or hydroxyl substitutions at the 2-, 3- and/or 4-position of the aliphatic moiety of butyrate. 4. The present study reveals a dissociation between the induction of apoptosis, inhibition of cell proliferation, HDAC activity and LDH leakage. The results indicate differential responses of butyrate analogues in HT-29 and HCT-116 colorectal cancer cells.