BODY WEIGHT SWINGS INCREASE CARDIOVASCULAR RISK

Gain-and-loss weight cycling among patients with established coronary heart disease (CHD) was strongly and independently associated with risk of cardiovascular events and death, in new research published in the April 6, 2017 issue of the New England Journal of Medicine^[1].

The wider the swing, the greater the risk, write the authors, led by Dr Sripal Bangalore (New York University School of Medicine, New York City).

"This study showed a consistent association, regardless of what we controlled for, that the weight fluctuation itself was associated with risk of cardiovascular outcomes and death," Bangalore told heartwire from Medscape.

Among those in the highest fluctuation quintile (average variability about 8.5 lbs), risk increases were 64% for coronary events, 85% for cardiovascular events, 124% for mortality, 117% for MI, and 136% for stroke compared with the quintile with lowest average variation (2 lbs or less), according to the report.

"In all groups, we found weight fluctuation was bad, but it was particularly bad in already-obese patients," Bangalore said.

Also, weight variability was linked with new-onset diabetes among patients with CAD. Compared with the lowest-weight variability, those with the highest variability had a 78% higher risk of developing new-onset diabetes, the researchers found, and that finding was independent of traditional risk factors.

"This may be one of the reasons patients tend to do poorly if they have a lot of weight fluctuation," Bangalore said. "They tend to develop diabetes, and we know diabetes itself is a risk factor for CVD events."

The authors analyzed information from the 2005 Treating to New Targets (TNT) trial, which overall studied 10,001 stable patients with a history of MI, documented coronary disease, or prior coronary revascularization. As long reported by heartwire , those randomized to 80 mg/day vs 10 mg/day atorvastatin had steeper reductions in LDL-cholesterol levels and significant reductions in major CV events, particularly nonfatal MI over an average of 5 years.

Patient body weight, among other information, was tracked at 3, 6, 9, and 12 months and then every 6 months. Among the 9509 patients from TNT in the current post hoc analysis, each standard-deviation increase in body-weight variability (3.3 lbs to 4.2 lbs) was associated with a significant increase in risk of several clinical end points.

Hazard Ratio (HR) for Outcomes per 1-SD Increase in Body-Weight Variability 

Outcome	# of events	HR	P
Any coronary eventa	2091	1.04	0.01
Any cardiovascular eventb	2727	1.04	0.001
Death	487	1.09	0.001

a. A composite of death from coronary heart disease, angina, nonfatal MI, resuscitated cardiac arrest, or revascularization

b. A composite of any coronary event or cerebrovascular event, heart failure, or peripheral vascular disease

This study builds on findings from the Framingham Heart Study, in which people without cardiovascular disease at baseline who then had weight swings over decades tended to die of cardiovascular disease, according to Bangalore. But it also is limited in showing association rather than causation; it did not identify whether some of the observed weight changes were intentional, which would interact with prognosis.

Bangalore hopes the study can serve as further motivation to help patients maintain a healthy weight. Weight loss is still recommended for the overweight and obese, he notes, "but if you lose weight and gain it back, it's potentially harmful."

The study was sponsored by Pfizer. Bangalore reports personal fees from Daiichi-Sankyo, Boehringer Ingelheim, Pfizer, Merck, Menarini, Gilead Sciences, and Abbott Vascular outside the submitted work. Disclosures for the coauthors are listed on the journal website .