Methods
metabolic syndrome
HYPOGONADISM, DEFICIENCY, LIVER DISEASE, CARDIOMYOPATHY, ERECTILE DYSFUNCTION, FOOD ALLERGIES, METABOLIC SYNDROME, HEART FAILURE, NEOPLASTIC DISEASE
This open label randomized clinical trial was conducted at the Hospital de Clínicas de Porto Alegre (HCPA), Brazil, allocating participants to a low-carbohydrate diet or to their usual diet as a control group. The Random App from Apple Store was used for randomization. The participants, recruited through consecutive sampling, included men > 18 years of age diagnosed with metabolic syndrome and subnormal testosterone levels. The exclusion criteria were cardiomyopathy, heart failure, previous or current neoplastic disease, uncontrolled liver disease, current treatment for erectile dysfunction, used drugs known to interfere with testosterone levels, previous bariatric surgery, using appetite-regulating drugs and food allergies or intolerance. Periodic consultations were held with researchers and a nutritionist for 3 months. The initial and final evaluations involved the entire team, while monthly evaluations were only performed by the nutritionist. At the first visit, inclusion and exclusion criteria were investigated as well as the informed consent was obtained from all participants of the study.We used the U.S. National Cholesterol Education Program's Adult Treatment Program III (NCEP-ATP III) [Hypogonadism symptoms were assessed using the Androgen Deficiency in the Aging Male (ADAM) questionnaire [Anthropometric measurements were performed according to World Health Organization norms [The control group was instructed to continue eating normally but received guidance about healthy eating patterns. The low-carbohydrate group was instructed by a nutritionist, member of the study team, to reduce carbohydrate intake and increase protein and fat intake [Data analysis was performed using SPSS Statistics (IBM, Armonk, NY, USA). Descriptive statistics (mean, standard deviation, frequency) were used. Normal distribution of the data was evaluated with Shapiro Wilks test. Student’s t test and Mann–Whitney U tests were used for normally distributed and non-normally distributed quantitative variables, respectively. In the comparison of qualitative data, Chi-Square and McNemar tests were used, respectively for dependent and independent samples. Pearson correlation analysis was used to examine the relationships between parameters that show normal distribution. The study was approved by the Research Ethics Committee of the Hospital de Clínicas de Porto Alegre (2017–0523). This study was carried out in accordance with the Declaration of Helsinki and Brazilian regulatory guidelines and norms for research involving human beings (National Health Council Resolutions 466/12 and 441/11). This study was registered at Plataforma Brasil (CAAE 61,385,716.8.0000.5327) and clinicaltrials.gov (NCT05019859, 25/08/2021).