Objective: To compare weight loss in blacks and whites in the Trial of Nonpharmacologic Interventions in the Elderly (TONE).
Research methods and procedures: TONE enrolled 421 overweight white and 164 overweight black adults, 60 to 79 years old, with blood pressure well-controlled on a single, antihypertensive drug. Drug therapy withdrawal was attempted 3 months after randomization to counseling for weight loss, sodium reduction, both weight loss and sodium reduction, or to usual care, with follow-up for 15 to 36 months after enrollment. Statistical procedures included repeated measures analysis of covariance and logistic and proportional hazards regression.
Results: In the weight-loss condition, net weight change (in kilograms) was -2.7 in blacks and -5.9 in whites (p < 0.001; ethnic difference, p = 0.0002) at 6 months and -2.0 (p < 0.05) in blacks and -4.9 (p < 0.001) in whites at the end of follow-up (ethnic difference, p = 0.007). In weight/sodium, net weight change was -2.1 (p < 0.01) in blacks and -2.8 (p < 0.001) in whites at 6 months, and -1.9 in blacks and -1.7 in whites at the end of follow-up (p < 0.05; ethnic difference, p > 0.5). Exploratory analyses suggested a more favorable pattern of weight change in blacks than in whites from 6 months onward. There was no ethnic difference in blood pressure outcomes.
Discussion: Whites lost more weight than blacks without, but not with, a concurrent focus on sodium reduction.