Karthik Murugiah

Prevalence of Takotsubo cardiomyopathy in the United States

BACKGROUND The aim of this study was to describe the prevalence of Takotsubo cardiomyopathy (TTC), age-gender interaction, and various comorbidities associated with it based on nationwide hospitalization records. Takotsubo cardiomyopathy is an increasingly reported clinical syndrome; however, there are no data on its prevalence in the general US population. METHODS The Nationwide Inpatient Sample discharge records were queried for the year 2008 using the International Classification of Diseases, Ninth Revision, code 429.83. RESULTS There were 6,837 patients diagnosed with TTC among 33,506,402 hospitalizations in the Nationwide Inpatient Sample database. Women were found to have higher odds of developing TTC (odds ratio 8.8). Women >55 years old had 4.8 times higher odds for developing TTC when compared with women <55 years old. Smoking, alcohol abuse, anxiety states, and hyperlipidemia were commonly associated with TTC. The peak incidence of hospitalization for TTC was in summer. CONCLUSION Takotsubo cardiomyopathy was diagnosed in about 0.02% of all hospitalizations in the United States, mostly in elderly women with history of smoking, alcohol abuse, anxiety states, and hyperlipidemia.

The use of google trends in health care research: a systematic review.

Background Google Trends is a novel, freely accessible tool that allows users to interact with Internet search data, which may provide deep insights into population behavior and health-related phenomena. However, there is limited knowledge about its potential uses and limitations. We therefore systematically reviewed health care literature using Google Trends to classify articles by topic and study aim; evaluate the methodology and validation of the tool; and address limitations for its use in research. Methods and Findings PRISMA guidelines were followed. Two independent reviewers systematically identified studies utilizing Google Trends for health care research from MEDLINE and PubMed. Seventy studies met our inclusion criteria. Google Trends publications increased seven-fold from 2009 to 2013. Studies were classified into four topic domains: infectious disease (27% of articles), mental health and substance use (24%), other non-communicable diseases (16%), and general population behavior (33%). By use, 27% of articles utilized Google Trends for casual inference, 39% for description, and 34% for surveillance. Among surveillance studies, 92% were validated against a reference standard data source, and 80% of studies using correlation had a correlation statistic ≥0.70. Overall, 67% of articles provided a rationale for their search input. However, only 7% of articles were reproducible based on complete documentation of search strategy. We present a checklist to facilitate appropriate methodological documentation for future studies. A limitation of the study is the challenge of classifying heterogeneous studies utilizing a novel data source. Conclusion Google Trends is being used to study health phenomena in a variety of topic domains in myriad ways. However, poor documentation of methods precludes the reproducibility of the findings. Such documentation would enable other researchers to determine the consistency of results provided by Google Trends for a well-specified query over time. Furthermore, greater transparency can improve its reliability as a research tool.

Publication and reporting of clinical trial results: cross sectional analysis across academic medical centers.

Objective To determine rates of publication and reporting of results within two years for all completed clinical trials registered in ClinicalTrials.gov across leading academic medical centers in the United States. Design Cross sectional analysis. Setting Academic medical centers in the United States. Participants Academic medical centers with 40 or more completed interventional trials registered on ClinicalTrials.gov. Methods Using the Aggregate Analysis of ClinicalTrials.gov database and manual review, we identified all interventional clinical trials registered on ClinicalTrials.gov with a primary completion date between October 2007 and September 2010 and with a lead investigator affiliated with an academic medical center. Main outcome measures The proportion of trials that disseminated results, defined as publication or reporting of results on ClinicalTrials.gov, overall and within 24 months of study completion. Results We identified 4347 interventional clinical trials across 51 academic medical centers. Among the trials, 1005 (23%) enrolled more than 100 patients, 1216 (28%) were double blind, and 2169 (50%) were phase II through IV. Overall, academic medical centers disseminated results for 2892 (66%) trials, with 1560 (35.9%) achieving this within 24 months of study completion. The proportion of clinical trials with results disseminated within 24 months of study completion ranged from 16.2% (6/37) to 55.3% (57/103) across academic medical centers. The proportion of clinical trials published within 24 months of study completion ranged from 10.8% (4/37) to 40.3% (31/77) across academic medical centers, whereas results reporting on ClinicalTrials.gov ranged from 1.6% (2/122) to 40.7% (72/177). Conclusions Despite the ethical mandate and expressed values and mission of academic institutions, there is poor performance and noticeable variation in the dissemination of clinical trial results across leading academic medical centers.

Assessing the Credibility of the “YouTube Approach” to Health Information on Acute Myocardial Infarction

This study was designed to assess the credibility of YouTube video information on acute myocardial infarction by exploring the relationship between accuracy of information on the topic, source of expertise, and perceived credibility of the message.

Sex Differences in the Rate, Timing, and Principal Diagnoses of 30-Day Readmissions in Younger Patients with Acute Myocardial Infarction

Background— Young women (<65 years) experience a 2- to 3-fold greater mortality risk than younger men after an acute myocardial infarction. However, it is unknown whether they are at higher risk for 30-day readmission, and if this association varies by age. We examined sex differences in the rate, timing, and principal diagnoses of 30-day readmissions, including the independent effect of sex following adjustment for confounders. Methods and Results— We included patients aged 18 to 64 years with a principal diagnosis of acute myocardial infarction. Data were used from the Healthcare Cost and Utilization Project-State Inpatient Database for California (07–09). Readmission diagnoses were categorized by using an aggregated version of the Centers for Medicare and Medicaid Services’ Condition Categories, and readmission timing was determined from the day after discharge. Of 42 518 younger patients with acute myocardial infarction (26.4% female), 4775 (11.2%) had at least 1 readmission. The 30-day all-cause readmission rate was higher for women (15.5% versus 9.7%, P<0.0001). For both sexes, readmission risk was highest on days 2 to 4 after discharge and declined thereafter, and women were more likely to present with noncardiac diagnoses (44.4% versus 40.6%, P=0.01). Female sex was associated with a higher rate of 30-day readmission, which persisted after adjustment (hazard ratio, 1.22; 95% confidence interval, 1.15–1.30). There was no significant interaction between age and sex on readmission. Conclusions— In comparison with men, younger women have a higher risk for readmission, even after the adjustment for confounders. The timing of 30-day readmission was similar in women and men, and both sexes were susceptible to a wide range of causes for readmission.

Association of Admission to Veterans Affairs Hospitals vs Non–Veterans Affairs Hospitals With Mortality and Readmission Rates Among Older Men Hospitalized With Acute Myocardial Infarction, Heart Failure, or Pneumonia

IMPORTANCE Little contemporary information is available about comparative performance between Veterans Affairs (VA) and non-VA hospitals, particularly related to mortality and readmission rates, 2 important outcomes of care. OBJECTIVE To assess and compare mortality and readmission rates among men in VA and non-VA hospitals. DESIGN, SETTING, AND PARTICIPANTS Cross-sectional analysis involving male Medicare fee-for-service beneficiaries aged 65 years or older hospitalized between 2010 and 2013 in VA and non-VA acute care hospitals for acute myocardial infarction (AMI), heart failure (HF), or pneumonia using the Medicare Standard Analytic Files and Enrollment Database together with VA administrative claims data. To avoid confounding geographic effects with health care system effects, we studied VA and non-VA hospitals within the same metropolitan statistical area (MSA). EXPOSURES Hospitalization in a VA or non-VA hospital in MSAs that contained at least 1 VA and non-VA hospital. MAIN OUTCOMES AND MEASURES For each condition, 30-day risk-standardized mortality rates and risk-standardized readmission rates for VA and non-VA hospitals. Mean aggregated within-MSA differences in mortality and readmission rates were also assessed. RESULTS We studied 104 VA and 1513 non-VA hospitals, with each condition-outcome analysis cohort for VA and non-VA hospitals containing at least 7900 patients (men; ≥65 years), in 92 MSAs. Mortality rates were lower in VA hospitals than non-VA hospitals for AMI (13.5% vs 13.7%, P = .02; -0.2 percentage-point difference) and HF (11.4% vs 11.9%, P = .008; -0.5 percentage-point difference), but higher for pneumonia (12.6% vs 12.2%, P = .045; 0.4 percentage-point difference). In contrast, readmission rates were higher in VA hospitals for all 3 conditions (AMI, 17.8% vs 17.2%, 0.6 percentage-point difference; HF, 24.7% vs 23.5%, 1.2 percentage-point difference; pneumonia, 19.4% vs 18.7%, 0.7 percentage-point difference, all P < .001). In within-MSA comparisons, VA hospitals had lower mortality rates for AMI (percentage-point difference, -0.22; 95% CI, -0.40 to -0.04) and HF (-0.63; 95% CI, -0.95 to -0.31), and mortality rates for pneumonia were not significantly different (-0.03; 95% CI, -0.46 to 0.40); however, VA hospitals had higher readmission rates for AMI (0.62; 95% CI, 0.48 to 0.75), HF (0.97; 95% CI, 0.59 to 1.34), or pneumonia (0.66; 95% CI, 0.41 to 0.91). CONCLUSIONS AND RELEVANCE Among older men with AMI, HF, or pneumonia, hospitalization at VA hospitals, compared with hospitalization at non-VA hospitals, was associated with lower 30-day risk-standardized all-cause mortality rates for AMI and HF, and higher 30-day risk-standardized all-cause readmission rates for all 3 conditions, both nationally and within similar geographic areas, although absolute differences between these outcomes at VA and non-VA hospitals were small.

Trends in Short- and Long-Term Outcomes for Takotsubo Cardiomyopathy Among Medicare Fee-for-Service Beneficiaries, 2007 to 2012

OBJECTIVES The aim of this study was to assess trends in hospitalizations and outcomes for Takotsubo cardiomyopathy (TTC). BACKGROUND There is a paucity of nationally representative data on trends in short- and long-term outcomes for patients with TTC. METHODS The authors examined hospitalization rates; in-hospital, 30-day, and 1-year mortality; and all-cause 30-day readmission for Medicare fee-for-service beneficiaries with principal and secondary diagnoses of TTC from 2007 to 2012. RESULTS Hospitalizations for principal or secondary diagnosis of TTC increased from 5.7 per 100,000 person-years in 2007 to 17.4 in 2012 (p for trend < 0.001). Patients were predominantly women and of white race. For principal TTC, in-hospital, 30-day, and 1-year mortality was 1.3% (95% confidence interval [CI]: 1.1% to 1.6%), 2.5% (95% CI: 2.2% to 2.8%), and 6.9% (95% CI: 6.4% to 7.5%), and the 30-day readmission rate was 11.6% (95% CI: 10.9% to 12.3%). For secondary TTC, in-hospital, 30-day, and 1-year mortality was 3% (95% CI: 2.7% to 3.3%), 4.7% (95% CI: 4.4% to 5.1%), and 11.4% (95% CI: 10.8% to 11.9%), and the 30-day readmission rate was 15.8% (95% CI: 15.1% to 16.4%). Over time, there was no change in mortality or readmission rate for both cohorts. Patients ≥85 years of age had higher in-hospital, 30-day, and 1-year mortality and 30-day readmission rates. Among patients with principal TTC, male and nonwhite patients had higher 1-year mortality than their counterparts, whereas in those with secondary TTC, mortality was worse at all 3 time points. Nonwhite patients had higher 30-day readmission rates for both cohorts. CONCLUSIONS Hospitalization rates for TTC are increasing, but short- and long-term outcomes have not changed. At 1 year, 14 in 15 patients with principal TTC and 8 in 9 with secondary TTC are alive. Older, male, and nonwhite patients have worse outcomes.

The Variation in Recovery: Role of Gender on Outcomes of Young AMI Patients (VIRGO) Classification System: A Taxonomy for Young Women With Acute Myocardial Infarction.

Background— Current classification schemes for acute myocardial infarction (AMI) may not accommodate the breadth of clinical phenotypes in young women. Methods and Results— We developed a novel taxonomy among young adults (⩽55 years) with AMI enrolled in the Variation in Recovery: Role of Gender on Outcomes of Young AMI Patients (VIRGO) study. We first classified a subset of patients (n=600) according to the Third Universal Definition of MI using a structured abstraction tool. There was heterogeneity within type 2 AMI, and 54 patients (9%; including 51 of 412 women) were unclassified. Using an inductive approach, we iteratively grouped patients with shared clinical characteristics, with the aims of developing a more inclusive taxonomy that could distinguish unique clinical phenotypes. The final VIRGO taxonomy classified 2802 study participants as follows: class 1, plaque-mediated culprit lesion (82.5% of women; 94.9% of men); class 2, obstructive coronary artery disease with supply-demand mismatch (2a: 1.4% women; 0.9% men) and without supply-demand mismatch (2b: 2.4% women; 1.1% men); class 3, nonobstructive coronary artery disease with supply-demand mismatch (3a: 4.3% women; 0.8% men) and without supply-demand mismatch (3b: 7.0% women; 1.9% men); class 4, other identifiable mechanism (spontaneous dissection, vasospasm, embolism; 1.5% women, 0.2% men); and class 5, undetermined classification (0.8% women, 0.2% men). Conclusions— Approximately 1 in 8 young women with AMI is unclassified by the Universal Definition of MI. We propose a more inclusive taxonomy that could serve as a framework for understanding biological disease mechanisms, therapeutic efficacy, and prognosis in this population.

Seasonal Variation in Hypertensive Emergency Hospitalization

Hypertension affects approximately 65 million individuals in the United States. Despite the development of increasingly effective antihypertensive treatments over the past 4 decades, the incidence of hypertensive emergencies has not decreased, but rather may have increased. Although there is some seasonal variation in blood pressure (BP), there are no data on seasonal variation in hospitalizations for hypertensive emergencies. This variation in BP may affect hospitalizations rates and increased health care burden. The increase in BP in winter might be related to increased sympathetic tone due to increased plasma and urinary norepinephrine concentrations. This chronobiological predisposition to increased BP in colder months may be the basis for increased risk of stroke and acute myocardial infarction in the winter season. We assessed seasonal variation in admissions for hypertensive emergency from a large national hospitalization database. We examined the Nationwide Inpatient Sample (NIS) from 2000 to 2007. We used this dataset to gather information on the number of hospitalizations with a primary diagnosis of a hypertensive emergency using the International Classification of Disease—9th Revision codes. NIS is a nationally representative survey of hospitalizations conducted by the Healthcare Cost and Utilization Project in collaboration with participating states. It is the largest all-payer inpatient dataset in the United States and includes a 20% sample of US community hospitals that approximates 20% of all US community hospitals. Each entry also contains information on demographic details, including age, sex, race; insurance status; primary and secondary procedures; hospitalization outcome; total cost; and length of hospital stay. The NIS database also contains clinical and resource use information, with safeguards to protect the privacy of patients, physicians, and hospitals. The NIS database results have been shown to correlate well with other hospitalization discharge databases in the United States. The frequency of hospitalization for each month cumulative over 8 years was calculated and divided by number of days in that month to obtain the mean hospitalizations per day for each month. All calculations were carried out using the weighted estimates approximating nationwide population estimates. An estimated 456,259 12,386 (mean standard error) hospitalizations for a hypertensive emergency occurred in the United States from the beginning of the calendar year 2000 to the end of the calendar year 2007. These comprised 0.16% of all admissions in 2000 and 0.19% of all admissions in 2007. The number of hospitalizations per day in each month is shown in the Figure. In general, the number of hospitalization was maximum in the winter months and minimum in summer months. More specifically, the mean number of hospitalization each day (averaged over 8 years) was least in June (2820). There was a rising trend from June to February. The average number of hospitalization was highest in February (3115); thereafter, the hospitalization rate dropped to a nadir in June. Using the NIS database, we identified an impressive pattern of seasonal variation in hospitalizations for hypertensive emergency, with a significant increased frequency during colder months and lower frequency in warmer months. Previous studies have indeed documented a significant negative correlation between ambient temperature and BP. The present observation suggests a need for aggressive follow-up of patients for increase in BP in colder months. The seasonal variation in BP may also impact the frequency of cardiovascular event risk in winter months. The winter

Improvements in the Distribution of Hospital Performance for the Care of Patients With Acute Myocardial Infarction, Heart Failure, and Pneumonia, 2006–2011

Background:Medicare hospital core process measures have improved over time, but little is known about how the distribution of performance across hospitals has changed, particularly among the lowest performing hospitals. Methods:We studied all US hospitals reporting performance measure data on process measures for acute myocardial infarction (AMI), heart failure (HF), and pneumonia (PN) to the Centers for Medicare & Medicaid Services from 2006 to 2011. We assessed changes in performance across hospital ranks, variability in the distribution of performance rates, and linear trends in the 10th percentile (lowest) of performance over time for both individual measures and a created composite measure for each condition. Results:More than 4000 hospitals submitted measure data each year. There were marked improvements in hospital performance measures (median performance for composite measures: AMI: 96%–99%, HF: 85%–98%, PN: 83%–97%). A greater number of hospitals reached the 100% performance level over time for all individual and composite measures. For the composite measures, the 10th percentile significantly improved (AMI: 90%–98%, P<0.0001 for trend; HF: 70%–92%, P=0.0002; PN: 71%–92%, P=0.0003); the variation (90th percentile rate minus 10th percentile rate) decreased from 9% in 2006 to 2% in 2011 for AMI, 25%–8% for HF, and 20%–7% for PN. Conclusions:From 2006 to 2011, not only did the median performance improve but the distribution of performance narrowed. Focus needs to shift away from processes measures to new measures of quality.