Association between nutritional state and phase angle in symptomatic and asymptomatic htlv-1 infected patients

Introduction The nutritional status of symptomatic and asymptomatic human T-cell lymphotropic virus type 1 (HTLV-1) infected patients is understudied. The phase angle (PA) has been described in the scientific literature as a prognostic indicator of nutritional status, but this has not been sufficiently discussed in the literature. Therefore, neither the impact of the infection nor the disease’s progression is sufficiently known regarding the nutritional status, body condition or composition. Objective To compare the nutritional status of symptomatic and asymptomatic adult individuals infected by HTLV-1, using the PA and anthropometric measures as a prognostic indicator in the HTLV-1 infected population. Methodology This was an observational, cross-sectional study with symptomatic and asymptomatic HTLV-1 patients followed up at the Neurology outpatient clinic of the Evandro Chagas National Institute of Infectious Diseases (INI-FIOCRUZ), Brazil, from September 2015 to September 2019. Anthropometric measures and indices (body weight, height, body mass index-BMI, mid-upper arm circumference-MUAC, triceps skinfold - TSF, and mid- arm muscle circumference-MUAC), and bioimpedance (phase angle-PA, percentage of lean mass-%LM, and percentage of fat mass-%FM) were checked to assess the nutritional status. Anthropometric variables were classified according to reference values and compared between groups (symptomatic and asymptomatic). Individuals were considered malnourished when at least one of the nutritional assessment results was outside the reference values. PA was correlated with the nutritional status, and groups of symptomatic and asymptomatic were compared to each other. The R-project® program version 3.0.2 was used to analyze the data. Differences were considered significant when the p-value was ≤ 0.05. Results Ninety-one patients were evaluated, 33 (36.3%) asymptomatic and 58 (63.7%) symptomatic. The majority were female (61.5%) and the median age was 60 (55-58) years. Symptomatic participants, compared to asymptomatic, had a lower proportion of overweight/obesity (51.7% vs 78.8%; p =0.0171), lower BMI (25.47 ± 5.06 kg/m2 vs 30.08 ± 5.61 kg/m2; p = <0.001), MUAC (29.56 ± 5.13 cm vs 33.22 ± 4.21 cm; p =0.0011), and %FM (30.75% vs 36.60%; p =0.0064), however, had a higher %LM (68.95% vs 63.40%; p =0.0299). All participants presented PA, however there was no difference between symptomatic (5.74º ± 1.18) and asymptomatic (6.21º ± 1.16). Conclusion Overweight and obesity were prevalent, especially among asymptomatic participants. Symptomatic participants had lower BMI, MUAC and %FM. Mid-upper arm circumference was considered a good parameter for monitoring the nutritional status of people with HTLV, mainly in situations where weight measurement is not viable. PA was altered in both groups, therefore, it cannot be used as a disease progression indicator, but it does indicate that HTLV infection alone should be a risk of cellular membrane integrity damage. Studies using PA assessment in HTLV-1 carriers are needed. AUTHOR’S SUMMARY HTLV is a disease very little explored, and in the scientific field of nutrition it is no different, we found few studies that associate this population and their nutritional status. In academic literature we can find the association of weight, height and BMI, rare studies with bioimpedance assessments. Until this moment, no study has associated nutritional status with the phase angle, which is being used in several infectious diseases as a prognostic indicator of cell membrane integrity. In this study, we note that even though the phase angle values are not significant, they show that, regardless of the symptoms, patients who are infected with the HTLV virus are already considered to have damage to the membrane integrity, which makes us emphasize the importance of new studies to a better understanding of factors related to weight gain and probable nutritional deficiencies. ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Trial N/A ### Funding Statement Yes. Initials of the authors who received each award. Only one author received financial support from Bacelo Grant numbers assigned to each author. Only one author received a Torres grant The full name of each funder URL of each funder's website http://www.faperj.br/ This work was funded by the Foundation for Research Support of the State of Rio de Janeiro (FAPERJ) (grant E-26/202.583/2017). This study was funded by the Fundação de Amparo a Pesquisa do Estado do Rio de Janeiro-FAPERJ. Funders had no role in study design, data collection and analysis, publication decision, or manuscript preparation. http://www.faperj.br ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: This study was approved by the Research Ethics Committee of the National Institute of Clinical Infectious Diseases Evandro Chagas, under number CAAE 46029415.9.0000.5262, on 09/14/2015 I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes If the data are all contained within the manuscript and/or Supporting Information files, enter the following: All relevant data are within the manuscript and its Supporting Information files. This study was approved by the Research Ethics Committee of the National Institute of Clinical Infectious Diseases Evandro Chagas under number CAAE 46029415.9.0000.5262 on 09/14/2015 * AC : Arm Circumference AMC : Arm Muscle Circumference ATL : Leucemia/linfoma de células T BIA : Bioimpedance BMI : Body Mass Index ELISA : Enzyme Linked Immuno Sorbent Assay FM : Fat mass HTLV : Human T-cell Leukemia-lymphoma Virus INI Fiocruz : (Instituto Nacional de Infectologia, in portuguese) Evandro Chagas National Institute of Infectious LBM : Lean Body Mass LM : Lean mass MUAC : Mid-arm muscle circumference OMS : World Health Organization PA : Phase Angle PEM : Protein-energy malnutrition R : Resistance SISVAN : Vigilância alimentar e nutricional (Food and Nutrition Surveillance System) TCLE : Termo de Consentimento Livre e Esclarecido (Free and Informed Consent Term) TSF : Tricipital Skinfold TSP : Tropical spastic paraparesis TSP/HAM : Tropical spastic paraparesis / Myelopathy XC : Reactance