August 2, 2013
Older adults enrolled in a weight-loss intervention had greater short-term and 3-year weight loss than their younger counterparts, researchers found.
Overweight and obese adults over the age of 60 lost more weight with the aid of an Internet-based intervention and personal counseling shortly after the start of the intervention and after 3 years of follow-up than did younger participants, according to Laura Svetkey, M.D., of Duke University Medical Center, and colleagues.
However, older patients did not lose significant amounts of weight when assigned to a self-directed control intervention, the researchers wrote online in the journal Obesity.
The authors noted that 71% of adults over the age of 60 are overweight or obese, but that obesity-related cardiovascular disease risks and physical limitations—including hypertension, diabetes, metabolic syndrome and difficulty walking—could be improved through weight loss.
Prior research has indicated that behavioral weight-loss interventions are associated with significant weight loss, but the age-based effectiveness of these interventions has not been properly evaluated, particularly when delivered through a technological route.
The authors analyzed the effects of age on weight loss and maintenance of a weight-loss regimen in 1,032 overweight and obese adult patients with hypertension and/or dyslipidemia who participated in the Weight Loss Maintenance trial.
Participants were randomized to a 30-month intervention of behavioral weight loss, monthly personal counseling or unlimited access over the study period to an Internet-based behavioral intervention following a 6-month behavioral weight-loss intervention.
The study sample included patients as young as 25 and as old as 83, who were taking medication for hypertension or dyslipidemia. They were categorized by age group, which included 50 and younger, 51‒60 and 60+.
The researchers gathered data on weight, diet and estimates of weekly time spent engaged in moderate to vigorous physical activity, as well as demographic data, medication use, perceived current and ideal weight, weight loss history, perceived stress and depression.
Study outcomes included weight lost during the pre-randomization intervention and after 36 months of intervention.
At baseline, the older participants' weight "tended to be slightly lower," and "a smaller proportion of older participants were obese," with 73% of those over 60 being obese vs. 81% of those 50 or younger.
In the first phase of the study, older adults lost significantly more weight than younger participants, with 66% of older patients losing 4 kg or more vs. only 51% of participants ages 50 or younger losing that amount. The authors also noted that "the amount of phase one weight loss also tended to increase with age."
After the second phase of the study, older participants kept the weight off better than younger participants, with a mean weight regain of 6.54% among those 50 and younger, 5.47% among those 51 to 60 and 5.05% in those older than 60. Mean weight change between the groups was highest among those older than 60 vs. the youngest and middle age groups.
These trends were not significant in those who were in the control maintenance group.
"In the absence of any maintenance intervention, more weight regain occurred, indicating that further intervention is needed after initial weight loss," they concluded, adding that future research should determine optimal interventions for patients in the older age group.
The study was limited by a lack of understanding of biological and behavioral mechanisms, no measure of body composition and lack of smaller-sized age categories.
By Cole Petrochko, Staff Writer, MedPage Today