Longitudinal Trends and Risk Factors for Obesity Among Immigrants in Massachusetts.

Introduction: Little is known about the longitudinal trends and factors associated with obesity and overweight among U.S. immigrants and ethnic minorities.

Methods: At a large safety net health system in Massachusetts, 7,973 adults were followed retrospectively for 42.0 months on average from 2011 to 2016. Multivariate analyses were performed to identify factors associated with obesity (BMI ≥30 kg/m) and overweight (BMI ≥25 kg/m). Data were collected and analyzed in 2018-2019.

Results: Obesity prevalence and trends were highest among Mexican/Central American men (32.6% in 2011 to 42.5% in 2016, p=0.03) and Haitian/black Caribbean women (37.5% to 51.5%, p<0.01). Mexican/Central American men had 564% (OR=5.64, 95% CI=4.02, 7.91) and women had 432% (OR=4.32, 95% CI=2.99, 6.23) higher odds of obesity compared with white, non-Hispanic men and women, respectively. Baseline age, weight, and duration of follow-up were associated with obesity among men (OR=1.02, 95% CI=1.02, 1.03; OR=1.16, 95% CI=1.15, 1.17; and OR=1.17, 95% CI=1.06, 1.30, respectively) and women (OR=1.01, 95% CI=1.01, 1.02; OR=1.18, 95% CI=1.17, 1.19; and OR=1.44, 95% CI=1.29, 1.61, respectively). East/Southeast Asians had the lowest obesity burdens. Most weight gains (63% among men and 75% among women) took place within 3 years.

Conclusions: Longitudinal obesity and overweight trends increased among all immigrants and ethnic minorities, primarily within the first 3 years, but significant variations existed. Mexican/Central American men and Haitian/black Caribbean women were disproportionately affected, approaching or exceeding U.S. rates. Targeted early prevention and treatment strategies are needed to reduce health disparities in obesity and unhealthy weight gain among immigrants.