Cocaine Use Ups HF Readmission Risk for Nonobese Patients

Heart failure (HF) readmission risk was higher among nonobese patients with HF with reduced ejection fraction (HFrEF) who reported cocaine use compared with patients who also had HFrEF but were classified as obese and did not use cocaine, according to new research published in Cureus.¹

Cocaine is a powerful, and addictive, stimulant with short-term effects that include hypersensitivity, irritability, and paranoia, and long-term effects that include raised body temperature and blood pressure, fast or irregular heartbeat, and tremors and muscle twitches.²

For this analysis, patients were divided into 2 groups based on body mass index (BMI): 148 were classified as nonobese (<30 kg/m²) and 113, obese (≥30 kg/m²). The overall mean (SD) patient age was 59 (12.6) years, with those in the nonobese cohort being slightly older, at 61 (13) vs 56.3 (11.6) years; 78.2% were male patients, 35.6% had diabetes, and 49.1% were African American. Data for this retrospective chart analysis were from patients admitted to Metropolitan Hospital Center in New York City between January 2013 and December 2016. The primary outcome was readmission for HF within 30 days of discharge.

“Obesity and illicit drugs are independent risk factors for developing HF. However, recent studies have suggested that patients who already have HF and are obese have better clinical outcomes,” the study investigators wrote. “We aim to study the effect of cocaine use on this obesity paradox phenomenon as it pertains to HF readmissions.”

Fifty-four percent of patients had an ejection fraction below 25%, 31.7% had an ejection fraction of 25% to 34%, and 14.3% had an ejection fraction of 35% to 40%. More patients in the nonobese cohort had ejection fractions below 25% and between 25% and 34% compared with the obese cohort: 58.1% vs 49.6% and 32.4% vs 29.2%, respectively.

Mean (SD) serum creatinine and hemoglobin levels were equivalent for the groups, at 1.43 (0.75) mg/dL and 12.2 (2.1) g/dL, respectively, in the obese group and 1.42 (1.08) mg/dL and 12.4 (2.0) in the nonobese group. More patients with nonobese status reported cocaine use vs patients with obese status: 19.6% vs 18.6% (P = .88).

The overall hospital readmission rate was 12.3%, with the patients who were readmitted having a lower mean (SD) BMI vs the patients not readmitted: 26.0 (5.0) kg/m² vs 31.0 (8.1) kg/m² (P = .002). The investigators determined this finding to be statistically significant.

Univariate analyses showed, too, that nonobese patients and cocaine users had 1.4-fold higher risks of 30-day hospital readmission vs obese patients and those who did not use cocaine, respectively:

• Nonobese vs obese: HR, 2.4 (95% CI, 1.09-5.38)
• Cocaine users vs nonusers: HR, 2.4 (95% CI, 1.16-4.97)

In addition, Kaplan-Meier analyses showed fewer HF readmissions post discharge among obese vs nonobese patients, at 7.1% vs 16.2% (P = .0253), and more readmissions for cocaine users vs nonusers, at 22.0% vs 9.9% (P = .0150).

Multivariate analysis that considered obesity status, cocaine use, age, length of stay, systolic blood pressure (SBP), and hemoglobin found that obesity status and noncocaine use “remained beneficial for HF prognosis in our study,” the authors wrote.

Moreover, HF readmission risk was shown to drop for every 1 g/dL increase in hemoglobin and for every 10 mm Hg rise in SBP:

• Hemoglobin: 18% reduced risk (HR, 0.82; 95% CI, 0.71-0.98)
• SBP: 14% reduced risk (HR, 0.86; 95% CI, 0.75-0.97)

A final analysis looked at the combined effect of cocaine use and obese status on 30-day readmission. Patients were classified as nonobese/cocaine use, nonobese/no cocaine use, obese/cocaine use, and obese/no cocaine use. With the obese/no cocaine use group serving at the reference, the highest likelihood of 30-day readmission by far was seen in the nonobese/cocaine use group, followed by the nonobese/no cocaine use and obese/cocaine use:

• Nonobese/cocaine use group: HR, 6.45 (95% CI, 2.3-17.41)
• Nonobese/no cocaine use: HR, 1.44 (95% CI, 0.57-3.64)
• Obese/cocaine use: HR, 0.74 (95% CI, 0.09-6.24)

“In view of the increase in the number of illicit drug users in the US in recent years, studies that explore the varying cardiotoxic effect of cocaine to educate the public are imperative,” the study authors emphasized, highlighting that their findings suggest having a high BMI conveys a protective effect against HF hospitalization despite reported cocaine use.

“Furthermore, continued cocaine use potentiates the effect of a low BMI on the risk of readmission after an acute HF hospitalization,” they added.

Moving forward, they recommend additional multicenter studies to corroborate their findings and optimizing treatment for patients who have anemia and hypotension prior to hospital discharge.

References

1. Akinlonu AA, Alonso A, Mene-Afejuku TO, et al. The impact of cocaine use and the obesity paradox in patients with heart failure with reduced ejection fraction due to non-ischemic cardiomyopathy. Cureus. Published online June 12, 2023. doi:10.7759/cureus.40298

2. What is cocaine? National Institute on Drug Abuse. April 2021. Accessed July 19, 2023. https://nida.nih.gov/publications/drugfacts/cocaine