Practice Update - ESC Congress 2017

He pointed to the fact that just one- quarter of underweight patients went on to undergo PCI after catheterization, vs one-third of morbidly obese patients and 40% of overweight and obese patients. Yet despite lower rates of PCI – thus, less obstructive coronary disease – underweight patients still faced much higher odds of dying during their index admission. “There must be some other relation- ship that explains this,” he said, which underscores for additional studies in the overlooked group. Dr. Tariq provided an important detail: whereas men made up the majority of patients in most of the weight groups studied, women were predominant in the underweight group. The observation feeds into prior biases that coronary heart disease disproportionately affects men more than women. He noted that while strides have been made in recent years to address this mis- conception, it may still be the case that a physician confronted with an overweight male patient is more likely to recommend aggressive risk factor control than he or she would in an underweight female patient. Dr. Tariq concluded, “The obesity paradox has flummoxed researchers for some time, and results of our research also flip the conventional wisdom that higher BMI should portend a worse outcome. We found that the lower-BMI group experi- enced worse outcomes across the board, including readmission, length of stay, cost, and mortality.” He continued, “Furthermore, using the largest all-payer publicly available database in the US, we observed that obese and morbidly obese patients received stents or balloons at a lower rate than normal-weight patients, were less likely to be readmitted within 30 days, and had lower mortality than normal- weight patients undergoing cardiac catheterization.” “Further research will certainly add to the growing body of evidence, but the scales seem to be tipping in favor of higher-BMI patients experiencing better outcomes than normal-weight patients. The results also reinforce the notion that the frail, those with lowest BMI, suffer the worst outcomes. They suggest that when it comes to cardiac catheterization, the smaller patients are, the harder they fall."

Overweight and obese patients had the lowest readmission rates, and were over 10% less likely to be readmitted than normal weight patients within 30 days. Further investigation is warranted to risk-stratify by BMI. Dr. Tariq explained that part of the result speaks to the burden of other diseases and risk factors seen in the lowest-rate group. For example, Elixhauser scores were higher in the underweight group than in any other group. According to Dr. Tariq, interventionists are not typically thinking of these patients as being high-risk for PCI. “The message is, don’t ignore your underweight populations,” he said. “We are always targeting the obese: be more active, go to the gym.” In underweight patients, the message needs to be different, he said, and physicians need to remember to screen for risk factors with the same degree of rigor typically reserved for obese patients. Others, he noted, have highlighted smoking as a particularly important risk factor in low- weight patients.

five times more likely to die than obese patients (6.0% mortality for underweight patients, 2.3% for normal weight, 1.7% for overweight, 1.2% for obese, 1.9% for morbidly obese, all P < .001 adjusted for comorbidities). Interestingly, despite extreme BMI, mor- bidly obese patients experienced a lower mortality rate than normal-weight patients, and obese patients experienced the low- est mortality of all groups undergoing cardiac catheterization. Length of stay for underweight patients was more than double that of normal- weight patients (10.5 vs 5.1 days), resulting in nearly 50%higher costs for underweight patients ($33,540 vs $22,581). Morbidly obese patients experienced a slightly longer length of stay and higher costs than normal-weight patients (6.2 days [P < .01] and $23,889 [P < .01]). After adjustment for comorbidities, under- weight patients were 18% more likely than normal-weight patients to be readmitted within 30 days (P < .007). Morbidly obese patients were 8.2% less likely to be read- mitted within 30 days (P < .001).

PracticeUpdate Editorial Team

ESC Congress 2017 • PRACTICEUPDATE CONFERENCE SERIES 17