Neuropeptide Y genotype, central obesity, and abdominal fat distribution: the POUNDS LOST trial

Background: Neuropeptide Y is a key peptide affecting adiposity and has been related to obesity risk. However, little is known about the role of NPY variations in diet-induced change in adiposity. Objective: The objective was to examine the effects of NPY variant rs16147 on central obesity and abdominal fat distribution in response to dietary interventions. Design: We genotyped a functional NPY variant rs16147 among 723 participants in the Preventing Overweight Using Novel Dietary Strategies trial. Changes in waist circumference (WC), total abdominal adipose tissue, visceral adipose tissue, and subcutaneous adipose tissue (SAT) from baseline to 6 and 24 mo were evaluated with respect to the rs16147 genotypes. Genotype dietary fat interaction was also examined. Results: The rs16147 C allele was associated with a greater reduction in WC at 6 mo (P < 0.001). In addition, the genotypes showed a statistically significant interaction with dietary fat in relation to WC and SAT (P-interaction = 0.01 and 0.04): the association was stronger in individuals with high-fat intake than in those with low-fat intake. At 24 mo, the association remained statistically significant for WC in the high-fat diet group (P = 0.02), although the gene dietary fat interaction became nonsignificant (P = 0.30). In addition, we found statistically significant genotype dietary fat interaction on the change in total abdominal adipose tissue, visceral adipose tissue, and SAT at 24 mo (P = 0.01, 0.05, and 0.04): the rs16147 T allele appeared to associate with more adverse change in the abdominal fat deposition in the high-fat diet group than in the low-fat diet group. Conclusion: Our data indicate that the NPY rs16147 genotypes affect the change in abdominal adiposity in response to dietary interventions, and the effects of the rs16147 single-nucleotide polymorphism on central obesity and abdominal fat distribution were modified by dietary fat. This trial was registered at clinicaltrials.gov as NCT00072995.