What’s considered optimum shape for people who are about to undergo cardiac surgery?
Mortality in patients who had undergone heart bypass surgery was over four times higher in individuals with a high body fat mass, according to new research conducted by Dr. Xavier Leroy of the Department of Anaesthesia and Resuscitation, CHU Lille, Lille, France and his colleagues.
Certain factors, including fat mass and lean body weight, may complicate cardiac surgery, the study found. Lean body weight is a person’s body weight minus fat, which can be roughly calculated by measuring their height, weight, girth and gender.
The team performed a retrospective study of 3,373 patients who had undergone elective cardiac surgery with cardiopulmonary bypass from January 2013 until December 2016.
Mortality within 30 days occurred in 2.1% of cases and significant differences were observed among body mass index, fat mass, and lean body weight. Unlike BMI, however, the higher a patient’s fat mass and BMI and the lower their lean body weight, the longer they spent in ICU.
“The 25% of patients with the highest fat mass were 4.1 times more likely to die than 25% with the lowest fat mass, and the 25% of patients with the lowest lean body weight were 2.8 times more likely to die than the 25% of patients with the highest lean body weight,” the study concluded.
BMI calculates weight, muscle, fat and bone in relation to height and gender. A BMI of 25 to 29.9 is considered overweight and those with a BMI of 30 or more are considered obese; morbidly obese people have a BMI of 44.9 or more.
The rate of adult obesity exceeds 30% of the population in 20 U.S. states and surpasses 35% in at least three states — Arkansas, West Virginia and Mississippi. Also, roughly 22 states have rates above 30%, 45 states are above 25%, and every state is above 20%.
There have been conflicting studies about obesity and mortality, known as the “obesity paradox.” In fact, a higher BMI may be associated with a lower mortality and a better outcome in several chronic diseases and health circumstances, previous research has shown.
That study noted that BMI is “crude and flawed” and doesn’t take into account fat mass, nutrition, cardiorespiratory fitness, body fat distribution, or other factors affecting mortality. A low body weight could also be the result of underlying illness rather than the cause.
However, previous research also suggests that the more overweight you are, the more likely you are to die prematurely. Weight gain in early and middle adulthood will increase health risks later in life, according to a 2017 study by researchers at the Harvard T.H. Chan School of Public Health.
People who gained a moderate amount of weight (5 to 22 pounds) before the age of 55 increased their risk of premature death, chronic diseases and decreased the likelihood of achieving healthy aging, the study found. And the higher the weight gain, the greater risk of chronic diseases.
The study analyzed data from nearly 93,000 participants.
Women gained an average of 22 pounds over this time, while men gained 19 pounds. “The findings indicate that even a modest amount of weight gain may have important health consequences,” senior author Frank Hu, professor of nutrition and epidemiology and chair of the Department of Nutrition, said in a statement.
Worse, early and middle adulthood is the time of life most people actually gain weight, as their metabolism slows and recurring knee and back injuries become more common, studies show. Many people are also less active in their 30s and 40s when they work longer hours.
Being overweight or obese is associated with a higher risk of dying prematurely than being a healthier weight, according to a separate international study released in 2016 also carried out by Harvard T.H. Chan School of Public Health and the University of Cambridge in the U.K.
Looking at specific causes of death, the study found that, for each five-unit increase in BMI (from, say, 30 to 35) the corresponding increases in risk were 49% for cardiovascular mortality, 38% for respiratory disease mortality and 19% for cancer mortality.