11/04/2024
By Lisa Merrill
Candidate Name: Lisa C. Merrill
Degree: Sc.D. in Epidemiology
Defense Date: Wednesday, Nov. 20, 2024
Time: 11 a.m. to Noon
Location: Room 245, Coburn Hall, South Campus
Title: “Dietary Intake and Bone Health, The Impact of Inflammation and the Gut Microbiome Among Adults From The Boston Puerto Rican Health Study.”
Dissertation Committee:
Chair: Kelsey M. Mangano, Ph.D., R.D.N., Associate Professor, Department of Biomedical and Nutritional Sciences, UMass Lowell
Members:
Sabrina E. Noel, Ph.D., RD, Associate Professor, Department of Public Health, UMass Lowell
Natalia Palacios, Ph.D., Associate Professor, Department of Public Health, UMass Lowell
Katherine L. Tucker, Ph.D. Professor Emeritus, Department of Biomedical and Nutritional Sciences, UMass Lowell
Yan Wang, Ph.D., Assistant Professor, Department of Psychology, UMass Lowell
Brief Abstract:
Osteoporosis (OP) is a major public health concern among Puerto Rican adults, representing a tremendous economic and health burden as Puerto Ricans are the second largest mainland U.S. Hispanic group. Preventive measures of osteoporosis are urgently needed for older Puerto Rican adults living in the U.S. and must begin with more comprehensive assessments of bone health. The current assessment of bone quantity (by bone mineral density) fails to capture differences in bone quality. Diet and the gut microbiome are suggested to impact inflammatory processes with downstream effects on bone quantity; however, these associations are understudied in measures of bone quality such as bone material strength index (BMSi) and trabecular bone score (TBS). To our knowledge, there are no studies of the potential relation between dietary quality and measures of gut microbial health on bone quality in this population.
The overarching goals of this dissertation are to 1) create a culturally adapted inflammatory score among mainland Puerto Rican adults and validate in native island Puerto Rican adults; 2) investigate the role of the gut microbiome in the association between diet quality and bone health; and 3) estimate the role of systemic inflammation in the association between intake of dairy products with bone quality.
Using data from the Boston Puerto Rican Health Study (n = 1500, aged 45-75 y at baseline) and The Puerto Rico Observational Study of Psychosocial, Environmental, and Chronic disease Trends (n = 1,591, aged 3-76 y) the first aim demonstrates that both published and culturally adapted dietary and lifestyle inflammation scores inconsistently predicted markers of inflammation. The second aim shows the Dietary Approaches to Stop Hypertension (DASH) diet quality score was predictive of bone quantity but not bone quality. Several gut microbial species were significantly associated with DASH, yet no microbial functional pathways were associated with DASH. Instead, health behaviors, gut microbial parameters, and dairy foods were associated with measures of bone quantity and quality (aim 3). This work is innovative in that it is the first to examine the relation of dietary intake, the gut microbiome, inflammation, and novel measures of bone quality in a large cohort of adults who are underrepresented in health research and who experience a higher prevalence of chronic disease, including poor bone health, compared to other racial and ethnic groups. This work may inform future interventions and public health strategies on the benefits of beneficial foods for the gut microbiome, inflammation, and bone, helping to mitigate the health disparities of this population.