Acculturation and biological stress markers: A systematic review.

Abstract Background The association of acculturation with health among immigrant populations is believed to be mediated, in part, by acculturation-related stress and stress biology. Objectives To review and qualitatively synthesize empirical findings on the relationship of acculturation with stress-related inflammatory and endocrine biomarkers and composite allostatic load (AL) scores. Methods A literature search was performed in the PubMed and PsycInfo databases. Article titles, abstracts or full-texts were screened and checked for match with the search criteria. Studies were eligible if they empirically tested the relationship between acculturation and inflammatory/endocrine stress biomarkers or composite AL scores, and were published in the English language. Results Among the 41 articles identified as relevant and included in this review, the majority were published after 2010, included adult Hispanic U.S.-based populations, used cross-sectional study designs, operationalized acculturation as a unidimensional construct, and varied considerably in the selection of covariates in the analyses. Acculturation was significantly associated with stress biomarkers in 29 studies, but the direction of effects varied across studies. Specifically, acculturation, operationalized as a higher orientation towards the host culture, was associated with inflammatory biomarkers in 10 of 14 studies, with endocrine stress biomarkers in 12 of 20 studies, and with composite AL scores in 7 of 8 studies. Overall, language-based proxy measures of acculturation were related to higher levels of stress-related inflammatory and endocrine biomarkers and to lower levels of AL scores, whereas nativity-, generation status- and length of stay-based proxy measures of acculturation were related to higher levels of inflammatory biomarkers and AL score. Discussion The majority of studies reported associations between measures of acculturation and stress biomarkers, however the directions of effects varied across studies. We suggest this heterogeneity may, in part, be a function of limitations imposed by cross-sectional research designs and unidimensional measures of acculturation measures, and we highlight the need for longitudinal studies and use of multidimensional measures of acculturation to better uncover the biobehavioral mechanisms and pathways linking acculturation with health outcomes.