CLEVELAND – , an observational study suggests.
The new findings, based primarily on 15 years of data from the National Health and Nutrition Examination Survey (NHANES), may argue against time-restricted diet interventions like intermittent fasting for patients with HF, researchers say.
The study’s nearly 1,000 participants on medical therapy for HF reported a mean daily eating window of 11 hours and daily average of four “eating occasions,” defined as meals or snacks of at least 50 kcal.
A daily eating window of 11 or more hours, compared with less than 11 hours, corresponded to a greater than 40% drop in risk for CV mortality (P = .013) over 5-6 years, reported Hayley E. Billingsley, RD, CEP, Virginia Commonwealth University, Richmond, Va,, at the annual scientific meeting of the Heart Failure Society of America.
The analysis adjusted for caloric intake, daily number of eating occasions, body mass index (BMI), history of CV disease and cancer, diabetes, and a slew of other potential confounders.
Prior evidence, mostly from healthy people, has suggested that extended fasting during the day is associated with less physical activity, Ms. Billingsley said in an interview. So it may be that people with HF who spread out their calorie intake are more active throughout the day.
A longer time window for eating, therefore, may have indirect metabolic benefits and help preserve their lean body mass, possibly reducing CV risk in a patient group at risk for muscle wasting.
The findings add to earlier evidence from Ms. Billingsley’s center that suggests that expanded daily time windows for eating, especially later final food rather than earlier first food, may help boost CV fitness for patients with obesity and HF with preserved ejection fraction.
Intermittent fasting and other practices involving the timing of food intake have been studied for weight loss and metabolic health in mostly healthy people and patients with diabetes, she noted. “But it’s really underexplored in people with established cardiovascular disease.”
On the basis of admittedly “very preliminary” findings, it may be that some patients should not shorten their daily time windows for eating or engage in intermittent fasting, Ms. Billingsley said. It’s probably worth considering, before the approach is recommended, “what their risk is for malnutrition or sarcopenia.”
The current study included 991 persons who entered the NHANES database from 2003 to 2018. The patients self-identified as having HF, reported taking medications commonly prescribed in HF, and provided at least two “reliable” dietary recalls.
The average age of the patients was 68 years, and they had had HF for a mean of 9.5 years; 47% were women, three-fourths were White persons, two thirds had dyslipidemia, and a quarter had a history of cancer.
On average, their first eating occasion of the day was at about 8:30 a.m., and the last occasion was at about 7:30 p.m., for a time window of about 11 hours; daily calorie consumption averaged about 1,830 kcal.
About 52% died over the mean follow-up of 69 months; about 44% of deaths were from CV causes.
In a model adjusted for demographics, BMI, smoking status, times of eating occasions, CV disease, diabetes, and cancer history, the all-cause mortality hazard ratio for time windows ≥ 11 hours vs. < 11 hours was 0.236 (95% confidence interval, 0.07-0.715; P = .011).
The reduction was no longer significant on further adjustment for duration of HF, a score reflecting difficulty walking, nightly hours of sleep (which averaged 7.2 hours), daily number of eating occasions, and caloric intake, Ms. Billingsley reported.
But in the fully adjusted analysis, the HR for CV mortality for the longer vs. shorter time window was 0.368 (95% CI, 0.169-0.803; P = .013).
The issue deserves further exploration in a randomized trial, Ms. Billingsley proposed, perhaps one in which patients with HF wear accelerometers to track daily activity levels. “We’d love to do a pilot study of extending their eating window that really digs into what the mechanism of any benefit might be if we assign them to a longer time window and whether it’s related to physical activity.”
Ms. Billingsley reported no relevant financial relationships.
A version of this article appeared on Medscape.com.