The missense variant, rs373863828, in CREBRF plays a role in longitudinal changes in body mass index in Samoans

A missense variant, rs373863828, in CREBRF is associated with obesity in Polynesians. We investigate whether rs373863828 and other factors are associated with body mass index (BMI) rate-of-change between 2010 and 2017–19 in Samoans. We used sex-stratified models to test whether BMI rate-of-change was associated with rs373863828, baseline BMI, age, residence, physical activity, and household asset score in a cohort study of 480 Samoan adults measured in both 2010 (mean age 43.8 years) and 2017–19. Mean BMI increased from 32.1 to 33.5 kg/m2 in males (n = 220, p = 1.3 ×10−8) and from 35.9 to 37.8 kg/m2 in females (n = 260, p = 1.2 ×10−13). In females, the A allele was associated with a higher rate-of-change (0.150 kg/m2/year/allele, p = 1.7 ×10−4). Across 10-year age groups, mean BMI rate-of-change was lower in older participants. The BMI rate of change differed by genotype: it was, in females with AA genotype, approximately half that seen in GG and AG participants. In females lower baseline household asset scores were associated with a higher rate-of-change (p = 0.002). In Samoans, the minor A allele of rs373863828 is associated with an increased rate-of-change in BMI in females. On average, BMI of females with the AA genotype increased 0.30 kg/m2/year more than of those with the GG genotype. •We studied BMI rate-of-change between 2010 and 2017–19 in 480 Samoans.•BMI rate-of-change was 0.24 kg/m2/year for females and 0.17 kg/m2/year for males.•In females, the rs373863828 A allele was associated with a higher rate-of-change.•BMI of AA females increased 0.30 kg/m2/year more than of those with the GG genotype.•In females fewer baseline household assets associated with a higher rate-of-change.