The aim of this systematic mixed-studies review is to summarise barriers/facilitators to adherence to and/or consumption of oral nutritional supplements (ONS) among patients with disease-related malnutrition. In March 2022, the Cochrane CENTRAL, PUBMED, PsycINFO (Ovid) and CINAHL were searched for articles with various study designs, published since 2000. Articles were identified on the basis of ‘population’ (patients ≥18 years with malnutrition/at nutritional risk), ‘intervention’ (ONS with ≥2 macronutrients and micronutrients), ‘comparison’ (any comparator/no comparator) and ‘outcome’ (factors affecting adherence or consumption) criteria. A sequential exploratory synthesis was conducted: first, a thematic synthesis was performed identifying barriers/facilitators; and second, the randomised controlled trials (RCTs) were used to support these findings. The five WHO dimensions of adherence guided the analysis. Study inclusion, data extraction, analysis and risk-of-bias assessment (MMAT 2018) were carried out independently by two researchers. From 21 835 screened articles, 171 were included with 42% RCTs and 20% qualitative studies. The two major populations were patients with malignancies (34%) and older adults (35%). In total, fifty-nine barriers/facilitators were identified. Patients’ health status, motivation, product tolerance and satisfaction as well as well-functioning healthcare routines and support were factors impacting ONS consumption. Few barriers/facilitators ( n = 13) were investigated in RCTs. Two of those were serving a small ONS volume and integrating ONS into ward routines. Given the complexity of ONS adherence, non-adherence to ONS should be addressed using a holistic approach. More studies are needed to investigate the effect of different approaches to increase adherence to ONS.

In head and neck cancer, the combination of weight loss and elevated C-reactive protein levels means that patients have malnutrition as defined by the Global Leadership Initiative on Malnutrition (GLIM). This study aimed to identify impact factors for malnutrition as defined by the GLIM criteria among patients with head and neck cancer at the start of treatment and up to 12 months post-treatment. In a prospective, observational study, patient, tumour, treatment, and nutritional data from 229 patients with head and neck cancer were collected at the start of treatment and at three follow-ups (7 weeks after the start of treatment and at 3 and 12 months after the termination of treatment). These clinical variables were statistically analysed in relation to malnutrition at each follow-up using univariate and multivariate analyses. Malnutrition was defined according to the two GLIM criteria of >5% body weight loss during the last 6 months and C-reactive protein >5 mg/L. The following factors were predictive for malnutrition in the multivariate analysis performed 7 weeks after the start of treatment: moderate or severe mucositis, chemoradiotherapy ± surgery, and the need for nutritional support (total or partial use of tube feeding/parenteral nutrition). Advanced tumour stage (III-IV) was significant for malnutrition at the start of treatment and at the 7 week and 3 month follow-ups, but not at 12 months. Severe mucositis, chemoradiotherapy ± surgery, and advanced tumour stage were found to be impact factors for the diagnosis of malnutrition using GLIM at different follow-up times from the start of treatment up to 12 months after the end of treatment. Few patients with head and neck cancer are diagnosed with malnutrition according to the GLIM criteria in a long-term perspective after the termination of treatment. Research on the validity of the GLIM criteria is needed to build a comprehensive evidence base of impact factors for malnutrition in head and neck cancer.

Patients with cancer deal with problems related to physical, psychological, social, and emotional functions. The aim was to investigate malnutrition defined by the Global Leadership Initiative on Malnutrition (GLIM) criteria in relation to health-related quality of life, anxiety, and depression in patients with head and neck cancer. This was a prospective observational research study with 273 patients followed at the start of treatment, seven weeks, and one year. Data collection included nutritional status and support, and the questionnaires: European Organization for Research and Treatment of Cancer Head and neck cancer module (EORTC QLQ-H&N35) and the Hospital Anxiety and Depression Scale (HADS). Malnutrition was defined using the GLIM criteria. The study showed that patients with malnutrition had significantly greater deterioration in their health-related quality of life at seven weeks. On a group level, health-related quality of life was most severe at this time point and some scores still implied problems at one year. Significantly, more patients reported anxiety at the start of treatment whereas significantly more patients reported depression at seven weeks. Over the trajectory of care, the need for support often varies. Psychosocial support is imperative and at the end of treatment extra focus should be put on nutritional interventions and managing treatment-related symptoms to improve nutritional status and health-related quality of life. In the long-term, head and neck cancer survivors need help to find strategies to cope with the remaining sequel.

Research on disease‐related malnutrition and adherence to oral nutritional supplements (ONS) has increased in recent years. To guide future studies, it is important to identify trends in terminology use and intervention characteristics. This review aimed to map characteristics of research investigating adherence to ONS in patients with disease‐related malnutrition and explore changes over time. This review is a secondary analysis of quantitative studies from a systematic mixed‐studies review. Online databases, including PubMed, Cinahl, Cochrane Central Register of Controlled Trials, and APA PsycInfo, were searched to identify studies published from 2000 to March 2022. A quantitative content analysis of extracted data was performed, and the Mixed Methods Appraisal Tool (MMAT) was used to assess methodological risk of bias. This review includes 137 articles, over half of which are randomized controlled trials (52%). The term “oral nutritional supplements” was used in 40% of the studies. Adherence to ONS was mainly described by the term “compliance” (69%). It was most common to offer ready‐made milk‐based ONS (56%) and ONS as a sole intervention (51%). The prescribed dose of ONS was fixed in 64% of studies and individualized in 22% of studies. There was variation in the methods used to assess adherence to ONS, and adherence was not reported in nearly a fifth of studies. There was an increase in methodological quality over time (p = 0.024). To ensure better understanding and increase the rigor and reproducibility of ONS intervention research, it is crucial to standardize the terminology used and to describe the interventions clearly.