FOOD INSECURITY AND MENTAL HEALTH DISPARITIES AMONG VULNERABLE POPULATIONS
Restricted (Penn State Only)
- Author:
- Dou, Nan
- Graduate Program:
- Nutritional Sciences
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- February 23, 2022
- Committee Members:
- Laura Murray-Kolb, Major Field Member
Xiang Gao, Major Field Member
Muzi Na, Chair & Dissertation Advisor
Runze Li, Outside Unit, Field & Minor Member
Gregory Shearer, Professor in Charge/Director of Graduate Studies - Keywords:
- food insecurity
Hispanic minorities
depression
stress
social support
longitudinal study
Food insecurity
Mental health
Heart rate variability
Vulnerable populations - Abstract:
- Food insecurity (FI) is prevalent globally and contributes to the adverse psychosocial or mental health outcomes. Vulnerable populations, such as immigrants, racial/ethnical minorities, and low-income adults are particularly vulnerable to food inequalities. FI is dynamically changed over time, and chronic or transitory FI may pose different challenges on mental health. Previous studies have extensively examined the associations between chronic FI and mental health in general or certain population groups. However, the universal existence and the directionality of the relations of FI and mental health are less learned in the vulnerable populations. In addition, the underlying pathways of how chronic or transitory FI influences mental outcomes are not clear. The goal of our first study was to determine if the relations of FI and adverse mental health universally exist in immigrant populations. Using repeated cross-sectional Gallup World Poll data from 2014-2019, the study accessed the prevalence of FI, mental wellbeing, and their associations among immigrants, as well as to compare the FI-mental wellbeing associations in immigrants and non-immigrants globally and by region. A total of 36,313 immigrants and 705,913 non-immigrants were included. Individual-level FI was measured with the FI Experience Scale. Mental wellbeing was assessed with the Negative Experience Index (NEI) and Positive Experience Index (PEI). A community attachment index was used to measure the living environment. The weighted proportion of any FI among global immigrants was 38.6% during 2014-2019. Compared to the food secure referent, FI was dose-responsively associated with greater NEI (coefficient [95%CI]: mild: 11.6 [10.8, 12.4], moderate: 19.2 [18.1, 20.2], and severe: 27.3 [26.1, 28.5], p-trend < 0.01) and lower PEI (mild: -8.2 [-9.0, -7.4], moderate: -11.4 [-12.4, -10.9], and severe: -15.5 [-16.6, -14.4], p-trend < 0.01). Region-specific analyses revealed similar dose-responsive associations (p-trend<0.01 for all regions). Community attachment significantly modified FI-mental wellbeing associations. Given the same FI status, immigrants reporting higher community attachment had lower NEI and higher PEI scores, compared to those with medium or low community attachment (p-interaction<0.01). Compared to non-immigrants, immigrants experienced poorer mental wellbeing when facing same food insecure situations, especially those who were severely food insecure and with medium to low community attachment. The goal of the second study was to examine the directionality of the associations between FI and psychosocial risk factors. This longitudinal study used data from the prospective Boston Puerto Rican Health Study cohort to examine how a group of psychosocial risk factors influence subsequent FI in a cohort of Puerto Rican adults over 5 y follow-up. A total of 517 Puerto Rican participants aged 45–75 y in the Boston area who were food secure at baseline, and who completed food security surveys at baseline and 5 y were included. Psychosocial factors, including depressive symptoms, stress, tangible social support, and acculturation were assessed with validated instruments. The cumulative incidence of FI at 5 y was 12.6%. The odds of incident FI were significantly associated with baseline depressive symptom score [OR = 1.78 (1.16, 2.76) per each 10 score units], with change in depressive symptom score [OR = 1.50 (1.07, 2.09) per each 10-unit increase], and with change in perceived stress [OR = 1.59 (1.01, 2.51) per each 10-unit increase]. The goal of the third study was to demonstrate the associations of FI impacting mental health assessed via heart rate variability (HRV), a known indicator of stress vulnerability. This longitudinal study collected a total of 789 person-days of data on FI and HRV from 29 healthy low-income adults in Central Pennsylvania. Data on FI (once daily in evening using the adapted 6-item U.S. Adult Food Security Survey Module module) and HRV (once daily, 5 mins upon awakening) were collected in the 2nd–4th week in each survey month. Three time-domain HRV measures (SDNN, RMSSD, and pNN50, the higher the ‘better’) and one frequency-domain HRV measure (LF/HF Ratio, the lower the ‘better’) were derived. Chronic FI was defined when participants reported ≥3 affirmative responses assessed using the 10-item U.S. Adult Food Security Survey Module. In a given month, greater daily FI score was significantly associated with lower lnRMSSD (11 days, beta-coefficient ranges -0.18~-0.01), pNN50 (5 days, beta-coefficient ranges -5.37~-4.61), and higher LF/HF Ratio (3 days, beta-coefficient ranges 0.29~0.33) mostly in week 3 and 4 of each month. Among participants without chronic FI, greater daily FI score was associated with decreased lnRMSSD (8 days, beta-coefficient ranges -0.31~-0.26) and pNN50 (7 days, beta-coefficient ranges -8.58~-6.20). Among participants reporting chronic FI, daily FI was associated with reduced lnRMSSD (3 days, beta-coefficient ranges from -0.20 to -0.18) and increased LF/HF ratio (5 days, beta-coefficient ranges from 0.32 to 0.70). Taken together, the results of this dissertation suggested that FI is a common concern and FI-adverse-mental-health associations universally exist in vulnerable populations. The psychosocial risk factors and their changes over time, particularly adverse mental health, are associated with future FI. Living environment also appears to modify the FI-mental health associations, especially among people with severe FI. Looking at the relations of FI impacting HRV, a time-varying association between daily FI and HRV was found within a given month, and this association may be altered by chronic FI status. Future studies are warranted to examine the bi-directional associations of FI and mental health in vulnerable populations, and larger studies with diverse population groups are needed to verify the relations of FI and HRV.