Individualized dietary counseling on nutritional status in head and neck cancer patients undergoing radiotherapy: A systematic review

Abstract

Individualized dietary counseling given with or without oral nutritional supplements, on the outcome of nutritional status, in head and neck cancer patients undergoing radiotherapy, compared to standard routine clinical care, with or without other nutritional interventions: A systematic review.

Background: Malnutrition and unintentional weight loss is common in patients with head and neck cancer. Malnutrition is a serious risk factor for morbidities, mortality, and heavily increased health care costs.

Nutritional interventions available today include individualized dietary counseling by a registered dietitian (RD), use of oral nutritional supplements, and the application of nutritional support by enteral tube feeding, and parenteral intravenous nutrition. Emerging research suggests that nutritional interventions may be helpful in decreasing unintended weight loss and malnutrition, reversing malnutrition and reducing its devastating consequences, but groups of experts recommend more research to draw firm conclusions about these effects.

Individualized regular dietary counseling by an RD throughout radiotherapy cancer treatment is not a standard treatment provided for head and neck cancer patients today. Rather, doctors may refer patients to an RD once malnutrition is already determined. Studies have shown effect of dietary counseling by an RD as one important nutritional intervention for patients at risk of malnutrition. More research is needed in order to ascertain the harms and benefits of making the intervention available to patients at risk of malnutrition and to patients with head and neck cancer undergoing radiotherapy, on a regular basis.

Objectives: To determine the effects of individualized dietary counseling by an RD, given with or without the use of oral nutritional supplements, on nutritional status, in adult patients with a diagnosis of head and neck cancer, who are, or will be undergoing radiotherapy treatment.

Methodology: This is a systematic review of randomized controlled trials (RCTs). It was conducted in accordance with the steps in The Cochrane Handbook of Systematic Reviews for Interventions 5th Edition. The population was both genders ≥19 years with a medical diagnosis of cancer of the head and neck who underwent radiotherapy cancer treatment with the intervention of one or more individualized dietary counseling sessions performed by an RD, given with or without the use of oral nutritional supplements. The comparator was standard routine clinical care with no individualized dietary counseling, with or without other nutritional interventions. The primary outcome was nutritional status measured by changes in weight and/or measured by changes in caloric intake. Secondary outcomes were quality of life, physical fitness, hospital readmissions, and mortality. Searches were technically performed by a skilled librarian in the following databases: MEDLINE (OVID), EMBASE (OVID), Cochrane Library (CENTRAL) (Wiley), CINAHL (EBSCO), Web of Science Core Collection (SCI-EXPANDED & SSCI) (Clarivate). Relevant data was extracted onto an excel sheet, and a narrative summary was constructed in a word document. Studies’ risk of bias (RoB) was performed for every included RCT in accordance with criteria of Cochrane. The Review Manager 5.4.1 (Revman 2020) tool, was used to generate forest plots for displaying results of two of the outcome measures, though not pooling results in meta-analysis, and tables displaying results for two outcome measures. A narrative summary grading of recommendations assessment, development, and evaluation (GRADE) assessment was performed to assess the certainty of the evidence.

Results: The database searches resulted in 969 studies after deletion of duplicates, the screening-process, full-text reading, and selection of studies that met inclusion criteria finally resulted in 3 studies presented in 4 articles. Three RCTs presented in four articles met the inclusion criteria for this systematic review, (n = 146 participants). The three RCTs were conducted in high income countries. The nutritional intervention for all three RCTs was dietary counseling by an RD where two of the studies included the use of oral nutritional supplements if this was deemed appropriate for participants, while one study only gave dietary counseling of ordinary foods without the use of oral nutritional supplements. Follow-up time for all included RCTs was 12 weeks, two studies gave nine dietary counseling sessions and one study gave seven sessions. Only two participants from the control group of one of the studies were given tube feeding due to rapid deterioration in nutritional status during the study period. All the three RCTs were assessed as having high risk of bias. All three studies measured outcomes on changes in weight, two studies measured outcomes on changes in energy intake, quality of life and physical function. None of the included studies measured mortality and hospital readmission. Results were not statistically pooled for any of the outcome measures due to insufficient data reporting. Further, meta-analyses were deemed inappropriate due to the studies’ high risk of bias which could further produce erroneous pooled results. All results favored dietary counseling given with or without oral nutritional supplements, although the effect estimates greatly differed. Results of the included studies suggest, with low and very low quality of evidence, that dietary counseling given with or without the use of oral nutritional supplements, may improve nutritional status in patients with head and neck cancer undergoing radiotherapy compared to standard clinical care with or without other nutritional interventions.

Author’s conclusions: From this systematic review, evidence of low and very low quality suggests that dietary counseling during radiotherapy for head and neck cancer patients, given with or without oral nutritional supplements may improve weight, energy intake, quality of life and physical function. Adequately powered RCTs, performed with pristine methodology ensuring appropriate blinding, and even multi-center studies are required to evaluate these effects in the future.