Introduction

Rates of overweight and obesity have increased in the military, particularly in the U.S. Navy. While the Navy has implemented weight-management programs like ShipShape, findings on the effectiveness of these programs are mixed. Further knowledge on the characteristics of service members (SMs) who participate in these programs may help inform course curricula and improve outcomes. This study aimed to (1) examine characteristics of SMs referred to the Navy's ShipShape program at a large military treatment facility, (2) compare these characteristics among SMs who did and did not enroll in a randomized clinical trial of ShipShape (ShipShape study participants), and (3) compare demographic and health characteristics of ShipShape study participants to that of a random and similarly sized sample of Navy SMs who responded to the 2015 DoD Health-Related Behaviors Survey (HRBS).

Materials and methods

Data from active duty Navy SMs referred to the ShipShape program at a large military treatment facility were evaluated (n = 225). A subset of these SMs enrolled in the ShipShape study (n = 187). Among enrolled SMs, data from 147 who completed all measures were compared to that of HRBS respondents. Univariate ANOVA and chi-square analyses were used to examine (1) demographic and motivational differences between SMs who did and did not enroll in the ShipShape study and (2) differences in demographics and medical and mental health conditions between ShipShape study participants and Navy HRBS respondents.

Results

The majority of SMs referred to ShipShape were female with an average age of 28.3 years. Compared to SMs who did not enroll in the ShipShape study (n = 38), ShipShape study participants were more likely to be female, less likely to be Hispanic, and had higher motivation and emotional eating scores. Compared to Navy HRBS respondents (n = 164), ShipShape study participants (n = 147) were younger, more likely to be female, non-Hispanic, enlisted, and obese. Further, ShipShape study participants reported significantly fewer medical health conditions but higher rates of probable depression, anxiety, and PTSD and were more likely to report receiving current mental health treatment than HRBS respondents.

Conclusion

Overweight or obese SMs seeking weight loss in the ShipShape study were relatively young, female, non-Hispanic, motivated, but with greater emotional eating. ShipShape study participants endorsed few medical health conditions but had higher rates of probable mental health conditions compared to the HRBS sample. These findings suggest that SMs referred to Navy weight-management programs are likely experiencing comorbid mental health conditions which may interfere with the effectiveness of their weight loss efforts. The descriptive nature of this study and the focus on Navy SMs in only one ShipShape program may decrease the generalizability of our findings to participants at other locations. Nonetheless, these findings demonstrate the potential need for Navy weight-management programs that incorporate mental health treatment and address the specific needs of female and diverse SMs. A more comprehensive curriculum could improve the results of weight-management efforts, increase SM quality of life and fitness and thereby operational readiness.

Overweight/obesity and inadequate fitness in active duty personnel impact the wellbeing of service members and have significant costs for military readiness and budget. ShipShape (SS), the Navy's weight management program, was designed to promote nutritional, behavioral, and exercise education to service members. Although SS is an evidence-based program, about half of those who complete the program pass the Body Composition Assessment (BCA), one part of the Navy's comprehensive Physical Fitness Assessment (PFA). SS may not fully address underlying behavioral, psychological, and emotional barriers that influence poor eating and exercise habits. A novel solution to improve outcomes is to incorporate acceptance and commitment therapy (ACT) to promote mindful awareness of present moment experiences, improve psychological flexibility, and support commitment to behavior change. This paper describes a cohort-randomized controlled trial of ACT-enhanced SS (ACT + SS) compared to the standard SS-only program. Active duty service members referred to the SS program are randomized to receive 8-weekly ACT + SS or SS-only group interventions. Our aims are to: 1) determine the effectiveness of ACT + SS compared to SS-only; 2) examine psychological flexibility as a mechanism underlying intervention response; and 3) explore potential moderators of intervention response. The primary outcome is weight, one of the key components of the BCA; secondary outcomes include Body Mass Index (BMI), body fat %, self-reported BCA results, physical activity, problematic eating, and quality of life. We have designed a cohort-randomized trial with interventions that are pragmatically implemented in a real-life military setting, and outcomes that are immediately relevant to service members and leadership.

Mycobacterium tuberculosis (Mtb) causes 1.6 million deaths annually. Active tuberculosis correlates with a neutrophil-driven type I interferon (IFN) signature, but the cellular mechanisms underlying tuberculosis pathogenesis remain poorly understood. We found that interstitial macrophages (IMs) and plasmacytoid dendritic cells (pDCs) are dominant producers of type I IFN during Mtb infection in mice and non-human primates, and pDCs localize near human Mtb granulomas. Depletion of pDCs reduces Mtb burdens, implicating pDCs in tuberculosis pathogenesis. During IFN-driven disease, we observe abundant DNA-containing neutrophil extracellular traps (NETs) described to activate pDCs. Cell-type-specific disruption of the type I IFN receptor suggests that IFNs act on IMs to inhibit Mtb control. Single-cell RNA sequencing (scRNA-seq) indicates that type I IFN-responsive cells are defective in their response to IFNγ, a cytokine critical for Mtb control. We propose that pDC-derived type I IFNs act on IMs to permit bacterial replication, driving further neutrophil recruitment and active tuberculosis disease.