Among patients with colorectal cancer (CRC), computed tomography-derived body composition measures predicted cardiac risk better than BMI, a population-based retrospective cohort study found.
Major adverse cardiovascular events (MACE) — stroke, cardiovascular death, and myocardial infarction — correlated with muscle radiodensity (HR 0.67 for highest vs lowest quintile, 95% CI 0.44-1.03) and with visceral adipose tissue area (HR 1.54 for highest vs lowest quintile, 95% CI 1.02-2.31).
While BMI was positively associated with certain measures of body composition, it didn’t predict MACE on its own, reported Justin Brown, PhD, of the Pennington Biomedical Research Center in Baton Rouge, Louisiana, and colleagues in JAMA Oncology.
A BMI in the obese range (35 or greater) didn’t carry significantly greater risk than a normal weight BMI of 18.5 to 24.9 (HR 1.23, 95%CI 0.85-1.77).
Because of the four-fold higher cardiovascular disease risk in CRC than in the general population, the American Cancer Society’s survivorship guidelines suggest advising patients and taking BMI into account in risk assessment.
However, BMI is a very crude measure, noted Brown. Notably, these guidelines “were largely based on expert opinion, so there is very little data to guide what the recommendation should be,” he told MedPage Today.
Providers could consider incorporating quantitative measures of body composition that can be taken automatically from CT scans that are generally acquired during CRC diagnosis, the researchers noted.
“This precision prevention approach to cardiovascular risk management may help to cost-effectively allocate limited resources such as dietary and physical activity counseling to patients who may be most likely to benefit from lifestyle counseling,” they continued.
Data from studies like this should lead to studies of interventions that aim to lower visceral adiposity and improve muscle quality, suggested Michael Passarelli, PhD, of Geisel School of Medicine at Dartmouth in Hanover, New Hampshire, in an accompanying editorial. He pointed to clinical trials currently underway that evaluate exercise in patients with stage II or III CRC and the use of aspirin to prevent both cancer recurrence and cardiovascular disease.
Brown’s group evaluated all 2,839 patients in the Kaiser Permanente Northern California (KPNC) cancer registry ages 18 to 80 years who underwent surgical resection for CRC and were diagnosed with stage I to III invasive CRC. Measures of body composition were collected at the third lumbar vertebrae at a single point in time.
Exclusion criteria were no valid measures of body mass, poor quality CT images, a pre-CRC history of stroke or myocardial infarction, and lack of pelvic or abdominal CT images.
The mean age was 61.9 years, and 51.3% were female. Many patients were current (12%) or former (40%) smokers and had type 2 diabetes (20%), hyperlipidemia (49%), and hypertension (55%).
MACE occurred in 12.9% of the participants by a median follow-up of 6.8 years. The cumulative incidence of MACE following diagnosis was 3.4% at 1 year, 5.9% at 3 years, and 19.1% at 10 years.
Subcutaneous adipose tissue area was not correlated with MACE (HR 1.15 for highest vs lowest quintile, 95% CI 0.78-1.69), nor was muscle mass (HR 0.96 for highest vs lowest quintile, 95% CI 0.57-1.61).
The researchers acknowledged the limitations of the study as it was observational in nature, used administrative codes within the electronic medical record that limited data on patients behaviors, and only had physical activity measured for 8% of the group at diagnosis with CRC.
Further epidemiological investigations of cardiovascular disease risk and body composition risk after cancer should be robust enough to consider stroke and MI individually and broadly assess other heart and vascular conditions, noted Passarelli. Investigations designed to evaluate body composition change with time may also lead to novel perspectives, as could studies that use imaging to measure periaortic and pericardial fat, he added.
“Understanding whether body composition profiling can identify those susceptible to cardiac toxic effects from colorectal cancer treatments such as fluorouracil or capecitabine is also imperative,” he continued.
The study was supported by the National Cancer Institute of the National Institutes of Health.
Brown disclosed relationships with the National Cancer Institute.
Passarelli reported no disclosures.
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Source: MedicalNewsToday.com
