All-cause mortality was investigated among individuals who had heart failure as it related to their daily caloric intake and energy outcome.
The incidence of mortality was lower among patients with heart failure whose eating patterns included low or moderate carbohydrate intake, with overall study findings showing that the quality and food sources of their macro-nutrients can influence heart failure outcomes and that malnutrition is linked to poor outcomes among this patient population.
This study was recently published in Frontiers in Cardiovascular Medicine, with the authors noting, “No previous data exist about the dietary energy patterns and calorie intake in all-cause mortality of heart failure. Considering that generally accepted nutritional strategies to improve quality of life and outcome in patients with remain unmet, we designed this study to investigate the relationship between daily energy intake, different ratios of nutrient consumption, and all-cause mortality in patients wiho have heart failure, and explored the optimal calorie patterns for them.”
Mean (SD) age of the 991 study participants was 67.36 (12.9) years, 44.3% were women, and 59.5% reported a non-Hispanic White ethnicity. Data for this analysis came from the National Health and Nutrition Examination Survey for 2001 to 2014, with latent class analysis incorporated to create calorie intake pattern based on the calorie ratio of 3 major nutrients. All-cause mortality was the primary end point, and patients were stratified by carbohydrate energy classification into low (< 46.0% of energy from carbohydrates), medium (46.0%-54.4%), and high (> 54.47%) tertiles.
The median (IQR) overall calorie intake was 1617 (1222-2154) kcal/d, with even moderate malnutrition linked to a 1.15-times greater risk of death (HR, 2.15; 95% CI, 1.29-3.56). Compared with the patients who died over the course of the study, the patients with heart failure who remained alive had a higher body mass index (BMI; P < .001), lower risk of malnutrition (P < .001), and more energy intake (P = .019).
Mortality differences were not seen between women and men (P = .264).
When considering the carbohydrate tertiles, for the lowest tertile, participants got more of their calories from fat energy (75.5% got more than 37.2% of their total energy from fats), and in the highest tertile, less total energy from fats (less than 30.5% among 78.5% of study participants). These results corresponded to lower risks of death in the low and medium tertiles compared with the highest tertile:
Low carbohydrates: 24% reduced risk of death (HR, 0.76; 95% CI, 0.59-0.97)
Medium carbohydrates: 23% reduced risk of death (HR, 0.77; 95% CI, 0.60-0.98)
Using the Nutritional Risk Index, mild and moderate malnutrition were linked to greater risks of all-cause mortality (HRs of 2.01 and 2.15, respectively). This discrepancy disappeared, however, following multivariate adjustment that considered such characteristics as race, marital status, insurance status, education level, smoking status, and BMI, with no association found between different caloric intakes and all-cause mortality (P = .446).
Overall, the authors saw a linear relationship between energy intake from dietary patterns that included many carbohydrates and all-cause mortality (P for nonlinear = .557) and a nonlinear relationship between energy intake from moderate carbohydrate intake and all-cause mortality (P for nonlinear = .008).
Because their study results contradict recent findings that moderate carbohydrate intake (50%-55% of total energy intake) is linked to the lowest risk of all-cause mortality compared with low (< 40%) and high (> 70%) carbohydrate intake, the present study investigators note that patients who have heart failure could potentially benefit from a diet with higher fat intake.
“In our study, a low-carbohydrate pattern high fat and protein proportion was more likely to offer a better outcome for patients with heart failure when using a high-carbohydrate pattern as a reference,” they wrote. “What’s worse, low-fat diets are often accompanied by a high intake of carbohydrates to make up for the loss of energy. While the pro-inflammatory effects of carbohydrates may lead to a systemic inflammatory response.”
They add that further studies should focus on the underlying molecular mechanisms of carbohydrate energy intake among patients with heart failure, especially considering their finding of malnutrition resulting from insufficient caloric intake.
Fang Z, Wang Z, Cao X, et al. Association between energy intake patterns and outcome in US heart failure patients. Front Cardiovasc Med. Published online November 9, 2022. doi:10.3389/fcvm.2022.1019797