US hospitals are seeing increasing complications in patients with Takotsubo cardiomyopathy

US hospitals are seeing increasing complications in patients with Takotsubo cardiomyopathy

New research shows Takotsubo cardiomyopathy remains a leading cause of hospital deaths and complications, with men facing more than double the risk and outcomes during the Covid-19 era.

In a recently published study in theJournal of the American Heart AssociationResearchers evaluated the incidence of Takotsubo cardiomyopathy (TC) and associated complications in the United States (US). TC is a reversible left ventricular dysfunction triggered by physical stress, mainly in men, or emotional stress, mainly in women. TC exhibits racial and gender disparities and remains a significant cause of in-hospital morbidity and mortality. Although traditionally viewed as a temporary condition, the study highlights ongoing risks of serious complications and mortality.

About the study

In the present study, researchers examined the incidence of TC and associated complications in the United States. They used the Nationwide Inpatient Sample (NIS) database, which contains weighted and unweighted data for approximately 35 million and seven million hospitalizations, respectively. TC cases were identified with ICD-10 code i51.81. However, the study relied on ICD-10 codes, which are potentially subject to coding errors and did not differentiate between TC subtypes (e.g., TC type-type). TC patients aged at least 18 years between 2016 and 2020 in the NIS database were included.

The primary outcomes were cardiogenic shock, myocardial rupture, congestive heart failure (CHF), atrial fibrillation, stroke, and cardiac arrest. Patient and hospital demographics included age, ethnicity or race, gender, median household income, hospital bed size, hospital region, average length of hospital stay, hospital teaching status, average total cost, expected primary payer, and hospital control.

Proportions and 95% confidence intervals (CIS) were calculated for categorical variables, and odds ratios and 95% CIs were estimated for continuous variables. Five-year outcome data were assessed. Chi-square analysis was performed to assess categorical results. Multivariable linear regression was used to assess the association between length of hospital stay and independent variables.

Results

Between 2016 and 2020, 199,890 patients were hospitalized with TC out of over 148.7 million total weighted population in the NIS database. The annual incidence of TC did not show a consistent trend, but overall increased from 39,015 cases in 2016 to 41,290 in 2020. The average age of the TC patients was 67 years. Most patients were female (83%) and white (80%). TC incidence increased in all age groups between 2016 and 2020, but there was a notable increase in the age group 46 to 60 years (31–45 years), which researchers attributed to accumulated stressors, undertreated cardiovascular risks and hormonal changes in the Middle Ages.

White individuals had the highest TC incidence rate, followed by Native Americans, while black individuals had the lowest incidence. Socioeconomic factors were significantly different, such as hospital size, primary payer, and median household income. TC patients had larger hospital bed sizes and higher household incomes. Most patients had Medicare; TC rates were the highest in private nonprofit and urban teaching hospitals.

TC patients had a high burden of cardiovascular complications, including atrial fibrillation (20%), CHF (36%), cardiogenic shock (6.6%), stroke (5.3%), and myocardial rupture (0.02%) compared to non-TC patients. TC patients also had higher mortality (6.58%) than non-TC patients (2.4%), with an odds ratio of 2.86 for mortality. In addition, TC patients had a higher likelihood of cardiogenic shock, CHF, cardiac arrest, and myocardial rupture. The 1.5% increase in mortality from 2019 to 2020 coincided with the Covid-19 pandemic, which previous studies associated with increased stress-induced cardiac events.

TC patients were slightly more likely to have atrial fibrillation and were also twice as likely to have a stroke. Notably, the incidence of some complications increased over the years, while others, such as atrial fibrillation and myocardial rupture, remained stable. For example, mortality rates increased from 5.6% to 8.3%, stroke incidence increased from 4.9% to 5.9%, and CHF incidence increased from 34.7% to 37.6%, among others.

While mortality was stable by gender over time, it was double in men (11.2%) compared to women (5.5%). The researchers emphasized that hormonal differences, particularly lower estrogen levels in postmenopausal men and women, could explain this disparity, as estrogen has shown protective effects in animal models of stress-induced cardiomyopathy. Multivariable analysis revealed that TC was associated with death overall adjusted for age, ethnicity or race, sex, hypertension, diabetes, hyperlipidemia, smoking, chronic obstructive pulmonary disease, and chronic kidney disease. The median length of hospital stay for TC patients was four days and was consistent throughout the study period.

A multivariable linear regression showed that large hospital bed size, Native American race, Medicaid insurance, Black race, and Asian race were associated with longer hospital stays. Conversely, female gender, older age, private insurance, treatment in the South, West, or Midwest, and private nonprofit hospital ownership were associated with shorter hospital stays.

Conclusions

Taken together, the data suggest that individuals with TC have a significantly increased risk of various cardiovascular complications. Men have a higher mortality rate than women. Notably, no improvements in complications were observed during the study years. Study limitations include reliance on administrative coding (which may miss TC subtypes) and potential duplicate entries from hospital transfers or acquisitions. Further research into improving and managing care is needed to expand outcomes for these patients.

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