Mulasi, Urvashi2015-11-062015-11-062015-08https://hdl.handle.net/11299/175273University of Minnesota Ph.D. dissertation. August 2015. Major: Nutrition. Advisor: Carrie Earthman. 1 computer file (PDF); xii, 169 pages.Malnutrition among individuals with head and neck cancer (HNC) is of particular concern, with up to 40% - 57% with a compromised nutritional status even before beginning their treatment. Within the US, the prevalence of malnutrition has not been well-documented due to a lack of consensus on its definition and diagnosing markers. Therefore, the primary aim of this prospective natural history pilot study was to estimate the prevalence of malnutrition among individuals with HNC (n = 19) during and up to 3 months after treatment using the new Consensus malnutrition definition. The scored Patient-Generated Subjective Global Assessment (PG-SGA) was used as the reference standard to evaluate the sensitivity and specificity of the Consensus framework in defining malnutrition. Another aim of this research was to investigate the utility of raw bioimpedance parameters such as 50 kHz phase angle (PA) and 200 kHz/5 kHz impedance ratio (IR) to identify individuals with malnutrition, and to evaluate how bioimpedance markers relate to functional status outcomes. Finally, this research also assessed how malnutrition relates to quality of life (QoL) and self-efficacy perceptions among individuals with HNC. Results indicate that individuals with HNC are malnourished even before treatment initiation. Using the Consensus framework, 67% of our participants were malnourished before treatment; and the prevalence of malnutrition consistently increased during treatment and the post-treatment period. When compared to our reference standard PG-SGA, the Consensus criteria identified malnutrition with overall good sensitivity (95%) and specificity (43%). Bioimpedance markers PA and IR were useful in identifying individuals who were at increased risk for malnutrition and/or impaired functional status. From a psychosocial perspective, compared with well-nourished participants, malnourished individuals scored significantly lower in the global QoL and cognitive function scales and significantly higher in the disease- and treatment-related symptom scales and items. In the future, if clinicians are trained to assess malnutrition diagnostic markers before individuals with cancer undergo aggressive treatments, nutritional interventions could be initiated at an earlier time and loss in weight and/or lean tissue can be prevented. Early detection of malnutrition could also help with patient-specific intervention strategies aimed to improve overall health-related QoL outcomes.enBioelectrical impedance analysisHead and neck cancerMalnutritionNutrition assessmentPG-SGAQuality of life in cancerThesis or Dissertation