Nutritional Challenges and Treatment After Bariatric Surgery.

Bariatric surgery is an important weight loss tool in individuals with severe obesity. It is currently the most effective long-term weight loss treatment that lowers obesity-related comorbidities. It also has significant physiological and nutritional consequences that can result in gastrointestinal complications and micronutrient deficiencies. After gastric bypass, common clinical events that negatively affect nutritional status include malabsorption, dumping syndrome, kidney stones, altered intestinal bile acid availability, bowel obstruction, ulcer, gastroesophageal reflux, and bacterial overgrowth. Risk factors for poor nutritional status and excessive loss of lean body mass and bone include reduced dietary quality and inadequate intake, altered nutrient absorption, and poor patient compliance with nutrient supplementation. There are unique concerns in adolescents, older individuals, and individuals who become pregnant postoperatively. With careful management, health-care professionals can assist with long-term weight loss success and minimize the risk of acute and long-term nutrition complications after bariatric surgery.

Hypothalamic Inflammation Improves Through Bariatric Surgery, and Hypothalamic Volume Predicts Short-Term Weight Loss Response in Adults With or Without Type 2 Diabetes.

OBJECTIVE: Preclinical research implicates hypothalamic inflammation (HI) in obesity and type 2 diabetes pathophysiology. However, their pathophysiological relevance and potential reversibility need to be better defined. We sought to evaluate the effect of bariatric surgery (BS) on radiological biomarkers of HI and the association between the severity of such radiological alterations and post-BS weight loss (WL) trajectories. The utility of cerebrospinal fluid large extracellular vesicles (CSF-lEVs) enriched for microglial and astrocyte markers in studying HI was also explored. RESEARCH DESIGN AND METHODS: We included 72 individuals with obesity (20 with and 52 without type 2 diabetes) and 24 control individuals. Participants underwent lumbar puncture and 3-T MRI at baseline and 1-year post-BS. We assessed hypothalamic mean diffusivity (MD) (higher values indicate lesser microstructural integrity) and the volume of the whole and main hypothalamic subregions. CSF-lEVs enriched for glial and astrocyte markers were determined by flow cytometry. RESULTS: Compared with control group, the obesity and type 2 diabetes groups showed a larger volume and higher MD in the hypothalamic tubular inferior region, the area encompassing the arcuate nucleus. These radiological alterations were positively associated with baseline anthropometric and metabolic measures and improved post-BS. A larger baseline tubular inferior hypothalamic volume was independently related to lesser WL 1 and 2 years after BS. CSF-lEVs did not differ among groups and were unrelated to WL trajectories. CONCLUSIONS: These findings suggest HI improvement after BS and may support a role for HI in modulating the WL response to these interventions.

Exocrine pancreatic insufficiency following bariatric surgery: unveiling alternative aetiology-case report and short review.

Bariatric surgery (BS) is currently the most effective treatment for severe obesity, requiring ongoing multidisciplinary follow-up to ensure proper progress and nutrition post-procedure. Despite its favourable safety profile, it is not exempt from complications, one of which being exocrine pancreatic insufficiency (EPI). The underlying pathophysiological mechanisms of EPI after BS are multifactorial, including poorly synchronized pancreatic enzyme secretion with the passage of nutrients (pancreaticocibal or postcibal asynchrony), insufficient pancreatic stimulation and bacterial overgrowth. We conducted a short literature review of the topic through a case of a patient who underwent BS in our centre and subsequently developed EPI and severe malnutrition. EPI initially was attributed to the surgery, but after a comprehensive evaluation, an unexpected cause was revealed.

Prevalence of low skeletal muscle mass following bariatric surgery.

BACKGROUND AND AIMS: Evidence on the occurrence of low skeletal muscle mass (low-SMM) following bariatric surgery (BS) as well as on the impact of low-SMM antedating BS on post-surgical body composition (BC) are scant. In this context, we aimed to prospectively evaluate the prevalence of low-SMM prior to and up to 5 years after BS, and to evaluate pre-surgical low-SMM as an independent risk factor for the presence of low-SMM after BS. METHODS: Retrospective analysis of prospectively collected database. BC was assessed by bioelectrical impedance analysis (BIA). A BIA-based formula was used to calculate skeletal muscle mass (SMM). Class I and class II low-SMM were defined respectively as a SMM index (SMMI = SMM/height2) value between -1 and -2, or > -2 standard deviations from the gender-specific regression line of the BMI versus the SMMI relationship in our reference group. RESULTS: A total 952 subjects were included, with BC being available for 877 (92%) subjects at 12 months and for 576 subjects (60%) at 60 months after BS. Prior to surgery, and at 12-, or at 60-months after surgery, class I and class II low-SMM was ascertained respectively in 15.6% and 4.6%, 5.3% and 1.4%, and 16.6% and 6.3% of the study participants. Logistic regression analysis showed that the occurrence of low-SMM at 12- and 60-months follow-up, was independently predicted not only by age at the time of surgery [respectively, HR: 1.052 (95% CI 1.020-1.084), p = 0.001; and 1.042 (95% CI 1.019-1.066); p < 0.001] but also by the presence of low-SMM prior to surgery [respectively, HR: 10.717 (95% CI 5.771-19.904), p < 0.001; and 5.718 (95% CI 3.572-9.153); p < 0.001]. CONCLUSIONS: Our data suggest that a low-SMM phenotype occurs not only in obesity surgery candidates but also after BS, and that low-SMM prior to surgery is an important risk factor for low-SMM throughout post-surgical follow-up.

Clinical Impact of Mediterranean Diet Adherence before and after Bariatric Surgery: A Narrative Review.

The population suffering from obesity is rapidly increasing all over the world. Bariatric surgery has shown to be the treatment of choice in patients with severe obesity. A Mediterranean diet has long been acknowledged to be one of the healthiest dietary patterns associated with a lower incidence of many chronic diseases. The aim of the present narrative review is to summarize the existing research on the clinical impact of a Mediterranean diet before and after bariatric surgery, focusing on its effects on weight loss and improvement in comorbidities. Although the current knowledge is limited, this information could add value and emphasize the importance of adopting a Mediterranean diet before and after bariatric surgery.

Patients Undergoing Bariatric Surgery: a Special Risk Group for Lifestyle, Emotional and Behavioral Adaptations During the COVID-19 Lockdown. Lessons from the First Wave.

OBJECTIVES: To determine how the COVID-19 lockdown influenced the lifestyle, eating behavior, use of substances, mental health, and weight in patients who had undergone bariatric surgery (BS) and explore the self-perception of one's own health and fears related to COVID-19. METHODS: We performed a cross-sectional exploratory study in obesity patients who had undergone BS surgery > 1 year previously in a university hospital. Assessment was performed 40 days after initiating lockdown and included 2 periods: from April 24 until May 8 and during the initial de-escalation period: from May 9 until 22, 2020. A structured telephone interview and an online survey were administered. RESULTS: One hundred eighty-eight patients were interviewed; 156 also responded to the online survey (77% females, mean age 53.46 ± 10.48 years, mean follow-up 5.71 ± 4.30 years). Dietary habits were affected in 72% of the participants, with 15% reporting better diet planning; 83.5% reported having more sedentary behaviors; 27% and 36% showed depression and anxiety, respectively; and 45% of participants reported bad sleep quality. In relation to changes in the use of any substance, the use increased in the majority of patients who were previously users. Self-perception of one's own health and fears related to COVID-19 were only moderate. Finally, emotional eating and time since BS were statistically significant risk factors for predicting weight gain. CONCLUSIONS: Lockdown during COVID-19 pandemic negatively influenced the lifestyle, mental health, substance use, and weight in BS patients. These alterations were somewhat similar to those observed in the general population but more severe and with important clinical implications.

Weight-loss thresholds after bariatric surgery and cardiovascular outcomes: more is better.

BACKGROUND/OBJECTIVES: Whether the extent of weight loss (WL) modulates bariatric surgery (BS) cardiovascular benefits has scarcely been assessed. Several WL thresholds have been commonly used to classify BS patients as good or poor responders without a proven clinical relevance. We examined the relationship between the magnitude of WL after BS and post-surgery major adverse cardiovascular-event (MACE) incidence. We also compared the performance of three different insufficient weight-loss (IWL) criteria for their association with MACE. SUBJECTS AND METHODS: All individuals who underwent a primary Roux-en Y gastric bypass (RYGB) or sleeve gastrectomy (SG) in our institution at least six years before data analysis (12/2020) were included in the study. Data on MACE were available in 1638 of 1700 participants (96.4%). Proportional-hazard Cox analyses were performed to ascertain the association between MACE, WL, and the three IWL criteria. IWL was defined as: <50% excess weight loss (<50% EWL), <20% total body-weight loss (<20% TBWL), and -1 standard deviation of alterable weight-loss percentage (<1 SD% AWL). RESULTS: During a mean follow-up of 10.2 ± 2.8 years, 86 participants experienced a first post-surgery MACE. Higher WL at one year (HR: 0.77 (95% CI: 0.61-0.98)) and 5 years (HR: 0.63 (95% CI: 0.42-0.92)) was related to a lower incidence of MACE. All short-term criteria for defining IWL were similarly associated with MACE, yet <1 SD% AWL identified more at-risk subjects. Five-year TBWL < 20% and 5-year <1 SD-AWL% were significantly associated with a higher risk for CV events. TBWL < 20% identified more subjects at risk. CONCLUSIONS: The extent of WL is closely related to long-term MACE incidence. Patients who lost -1SD% AWL at one year or <20% TBWL at five years may be considered poor responders.

Psychosocial, Lifestyle, and Body Weight Impact of COVID-19-Related Lockdown in a Sample of Participants with Current or Past History of Obesity in Spain.

PURPOSE: Home lockdown and isolation due to COVID-19 have been related to negative changes in mood, sleep, and eating behaviors. People with obesity are especially vulnerable to emotional eating and might be more prone to weight gain and negative outcomes during lockdown. MATERIALS AND METHODS: Individuals scheduled for an appointment at the Obesity Unit of a Tertiary Hospital between March 16 and June 21 (n=1230). An online survey was distributed on May 11. Multivariable logistic regression models and general linear models were used to assess the relationship between perceived COVID-19 threat, BS status, and outcome variables. RESULTS: Of the 603 (72.0% females, 39% aged >55 years) respondents, 223 (36.9%) were BS naïve (non-BS), 134 (22.2%) underwent BS within the two previous years (BS<2y), and 245 (40.6%) more than 2 years before (BS>2y). Participants worried about being infected by COVID-19 showed significantly larger changes in family contact (p=0.04), mood (p<0.01), sleep (p<0.01), dietary habits (p=0.05), purchases of unhealthy food (p=0.02), snacking (p=0.05), and physical activity (p=0.02). Non-BS and BS>2y participants reported greater impact of lockdown in mood (p<0.01), experienced more negative changes in dietary habits (p<0.01), and had a higher likelihood for weight gain (OR: 5.61, 95% CI: 3.0-10.46; OR: 5.45, 95% CI: 2.87-10.35, respectively) compared to BS<2y. CONCLUSIONS: COVID-19 pandemic is having a substantial negative impact in our population affected by obesity. During lockdown, people more than 2 years before BS behave like people without history of BS. Strategies addressed to prevent negative metabolic outcomes in this population are urgently needed.

Emotional Resilience and Bariatric Surgical Teams: a Priority in the Pandemic.

The infection control measures implemented as a result of COVID-19 led to a postponement of bariatric surgical procedures across many countries worldwide. Many bariatric surgical teams were in essence left without a profession, with many redeployed to other areas of clinical care and were not able to provide the levels of patient support given before COVID-19. As the pandemic continues, some restrictions have been lifted, with staff adjusting to new ways of working, incorporating challenging working conditions and dealing with continuing levels of stress. This article explores the concept of emotional labour, defined as 'inducing or suppressing feelings in order to perform one's work', and its application to multidisciplinary teams working within bariatric surgery, to offer insight into the mental health issues that may be affecting healthcare professionals working in this discipline.

A Propensity Score Cohort Study on the Long-Term Safety and Efficacy of Sleeve Gastrectomy in Patients Older Than Age 60.

Background: Bariatric surgery (BS) in older obese subjects (>60 years of age) has risen in the past decade and will continue to rise in the coming years due to ageing of the population. Aim: To evaluate the short- (12 months) and long-term (60 months) results of laparoscopic sleeve gastroscopy (LSG) in patients older than age 60. Methods: We performed a retrospective review of patients prospectively included in a database from January 2007 to December 2013. All patients >60 [older group (OG)] who had undergone LSG were included. The control group (CG) included patients aged 50 to 59 years who had undergone LSG during the same period. Results: 116 (8.4 % of total surgery) and 145 patients were included in the OG and CG, respectively. BS in patients >60 years increased from 2.4% in 2003 to 14% in the last 2 years of the study. After inverse probability of treatment weighting (IPTW) analysis, all absolute standardized differences were <0.15. A 60-month follow-up was attained in 90% of patients in the OG and 74% in the CG. There were no significant differences in postoperative complications between the two groups. At 12 and 60 months after LSG, both groups achieved a similar body mass index. There was no statistical difference in the percentage of resolution of type 2 diabetes, hypertension, dyslipidemia, and SAHS between the two groups. In both groups, all the nutritional parameters evaluated remained within the normal range throughout the study. Conclusions: LSG provides acceptable outcomes and is safe in older adults indicating that age should not be a limitation to perform BS in this population.

The Impact of Age on the Prevalence of Sarcopenic Obesity in Bariatric Surgery Candidates.

BACKGROUND: Sarcopenia pre-dating bariatric surgery (BS) has been suggested as concern for the use of BS in older-adults with morbid obesity. OBJECTIVE: To evaluate the impact of age on the prevalence of sarcopenic obesity (SO) in BS-candidates. METHODS: Cross-sectional study including 1370 consecutive BS-candidates aged ≥18, and grouped according to age: 18-39 (reference group), 40-49, 50-59 and ≥ 60 years. From body composition analysis data obtained using bioelectrical impedance, skeletal muscle mass (SMM), SMM index (SMMI=SMM/height2), and percentage of SMM (%SMM = SMM/BW*100) were calculated. Class I or class II SO was adjudicated, respectively, when a value between > - 1 and - 2, or > -2 standard deviations from the regression line from the gender-specific distribution of the relationship between BMI and SMMI or the %SMM in the reference group was encountered. RESULTS: According to the SMMI distribution, prevalence of class I and class II SO in the whole cohort was respectively 16.4% and 4.6%. SO was more prevalent in females (p < 0.005). Proportion of subjects with SO positively correlated with older age category in females (Tau-c = 0.149, p < 0.001) but not in males. In females aged ≥60, class I SO was present in 29.1%, and class II in 12.8%. Similar results were obtained when %SMM was used (Cohen's k-coefficient = 0.886, p < 0.001). Age and female gender were identified as independent preditors of SO, whereas CRP or the presence of obesity-associated comorbidities were not. CONCLUSION: Age is a risk factor for SO in BS-candidates. SO is fairly common in female subjects aged >60 years that are candidates to BS.

Bariatric Support Groups Predicts Long-term Weight Loss.

BACKGROUND: Support groups are an integral part of bariatric surgery (BS) programs yet there is limited evidence for an association between support group attendance and BS weight outcomes. SETTINGS: University Hospital, Spain. OBJECTIVES: This study examined the effect of support group attendance on weight loss (WL) at short- and long-term follow-up (FU) following BS. METHODS: Participants were 531 (mean body mass index (BMI) = 45.8 (5.4) kg/m2; mean age 45.9 (11.1) years, 76.4% females) who underwent BS (Roux-en-Y gastric bypass (RYGB): 233 (43.8%); sleeve gastrectomy (SG): 298 (56.2%)) in our clinic. The bariatric support group program (BSGP) consisted of two subprograms: Novel-BSGP (N-BSGP; first 12 months after surgery) and Experienced-BSGP (E-BSGP; FU between 12 months 5 years after BS). RESULTS: Three hundred and twenty-three (60.8%) and 129 (24.3%) participants attended at least one session of N-BSGP and E-BSGP, respectively. Linear regression analyses showed that number of sessions attended during year 1 predicted percent total body WL (%TBWL (ß = 0.381, p < 0.001)) and percent excess WL (%EWL (ß = 0.928, p < 0.001)) at one year and number of sessions attended during years 2-5 were positively related to %TBWL and %EWL achieved at 5 years (%EWL: ß = 0.162 (p = 0.014) and %TBWL: ß = 0.378 (p = 0.013)) respectively. CONCLUSION: We observed a significant beneficial effect of a post-surgical support group program on short- and long-term body WL after BS.

Ten-year outcomes after Roux-en-Y gastric bypass and sleeve gastrectomy: an observational nonrandomized cohort study.

BACKGROUND: Sleeve gastrectomy (SG) has replaced Roux-en-Y gastric bypass (RYGB) as the most commonly performed bariatric surgery procedure. Data on the long-term (up to 10 yr) outcomes after SG is scarce. No previous study has compared the long-term outcomes between RYGB and SG. OBJECTIVE: To compare 10-year weight lost and 10-year remission rates of type 2 diabetes, hypertension, and dyslipidemia between RYGB and SG. SETTING: University hospital, Spain. METHODS: Nonrandomized cohort study including all patients that underwent RYGB or SG at our institution between January 2005 and March 2008. Participants were followed yearly after bariatric surgery. Data obtained at the 10-year evaluation after RYGB or SG (between January 2015 and March 2018) was analyzed. Main study outcomes were 10-year percentage of total weight lost and percentage of excess weight lost. Secondary outcomes included 10-year remission rates of type 2 diabetes, hypertension, and dyslipidemia. Between-groups differences in 10-year percentage of total weight lost and percentage of excess weight lost were evaluated using analysis of covariance. Association between type of surgery and remission rates of obesity-related co-morbidities were evaluated using logistic regression analyses. RESULTS: Five hundred four patients were included in the study, 390 underwent RYGB and 134 SG. Follow-up rate was 84.5%. Mean 10-year percentage of total weight lost and percentage of excess weight lost were 25.3 ± 11.2% and 56.0 ± 25.6% in the RYGB group, and 27.5 ± 13.5% and 53.2 ± 25.1% in the SG group (P = .853 and P = .746, respectively). In logistic regression analyses RYGB was superior to SG in achieving 10-year hypertension and dyslipidemia remission. CONCLUSIONS: This study suggested comparable effectiveness between SG and RYGB on weight loss.

Genetic background influences weight-loss trajectories on the mid-term after bariatric surgery.

Bariatric surgery (BS) is a highly effective therapy for morbid obesity, yet with a wide inter-individual variability on weight-loss responses. To determine genetic influence on weight loss after BS we compared the within-pairs difference in maximum percentage excess weight loss (%EWL) and the within-pairs %EWL differences over a mean follow-up of 53.6 ± 36.4 months between 47 pairs of first-degree relatives and 47 genetically unrelated control pairs. Within-pairs maximum %EWL difference was similar between first-degree related pairs and control pairs (p = 0.100). Within-pairs %EWL difference increased through follow-up (p < 0.001). However, effect of time was different depending on genetic background (ptime*group = 0.001). Increased variability in mid-term weight response was present in unrelated pairs but not in first-degree pairs (p < 0.001 and p = 0.535, respectively). To assess shared environment influence, 16 married couples were identified and 16 unrelated and non-cohabiting matched pairs were also analyzed. In these analysis within-pairs difference in %EWL also increase over time (p = 0.025) but no group by time effect was observed (ptime×group = 0.177). In conclusion first-degree related participants showed closer weight trajectories after BS time than genetically unrelated subjects. Genetic background might partially explain the variability in mid-term weight-loss after BS.

Effect of Protein Intake on the Protein Status and Lean Mass of Post-Bariatric Surgery Patients: a Systematic Review.

BACKGROUND: Post-bariatric surgery may compromise nutritional status due to energy and protein intake restriction. METHODS: Systematic review was performed to synthesize evidence on the amount of protein intake and its association with lean mass and serum proteins during at least 6 months following Roux-en-Y gastric bypass or sleeve gastrectomy. RESULTS: Twelve studies (n = 739) were identified in the search. Protein intake below 60 g/day and significant lean mass loss were observed in majority of these studies. Of the four studies that measured association between protein intake and lean mass retention, only two supported this hypothesis. CONCLUSION: There is insufficient evidence of the effect of dietary protein on serum protein levels. Further studies are needed to better estimate the protein intake that supports a healthy nutritional status in this population.

Effect on Nitrogen Balance, Thermogenesis, Body Composition, Satiety, and Circulating Branched Chain Amino Acid Levels up to One Year after Surgery: Protocol of a Randomized Controlled Trial on Dietary Protein During Surgical Weight Loss.

BACKGROUND: Bariatric surgery (BS), the most effective treatment for severe obesity, typically results in 40-50 kg weight loss in the year following the surgery. Beyond its action on protein metabolism, dietary protein intake (PI) affects satiety, thermogenesis, energy efficiency, and body composition (BC). However, the required amount of PI after surgical weight loss is not known. The current daily PI recommendation for diet-induced weight loss is 0.8 g/kg ideal body weight (IBW) per day, but whether this amount is sufficient to preserve fat-free mass during active surgical weight loss is unknown. OBJECTIVE: To evaluate the effect of a 3-month dietary protein supplementation (PS) on nitrogen balance (NB), BC, energy expenditure, and satiety in women undergoing either gastric bypass or vertical sleeve gastrectomy. METHODS: In this randomized prospective study, participants will be randomized to a high protein supplementation group (1.2 g/kg IBW per day) or standard protein supplementation group (0.8 g/kg IBW per day) based on current guidelines. Outcome measures including NB, BC, circulating branched chain amino acids, and satiety, which will be assessed presurgery, and at 3-months and 12-months postsurgery. RESULTS: To date, no studies have examined the effect of dietary PS after BS. Current guidelines for PI after surgery are based on weak evidence. CONCLUSIONS: The results of this study will contribute to the development of evidence-based data regarding the safe and optimal dietary PI and supplementation after BS. TRIAL REGISTRATION: Clinicaltrials.gov NCT02269410; http://clinicaltrials.gov/ct2/show/NCT02269410 (Archived by WebCite at http://www.webcitation.org/6m2f2QLeg).

Inflammation and iron status in bariatric surgery candidates.

BACKGROUND: Iron homeostasis is disturbed by the systemic inflammation commonly encountered in morbid obesity. However, inflammatory markers have seldom been considered in studies investigating the prevalence of iron deficiency (ID) in bariatric surgery (BS) candidates. The objective of this study was to evaluate the prevalence of ID and anemia with ID in BS candidates, accounting for inflammatory status as measured using high sensitivity C-reactive protein (hs-CRP), and to further characterize indices of iron status in BS candidates with systemic inflammation. PATIENTS AND METHODS: On the basis of ferritin, hemoglobin, and hs-CRP levels, iron status was categorized in 803 (85%) of 947 consecutive BS candidates. Ferritin<12 ng/mL in females and<15 ng/mL in males irrespective of hs-CRP level was classified as absolute-ID, whereas ferritin between those thresholds and 100 ng/mL was categorized as functional-ID (FID) if hs-CRP>3 mg/L. Anemia was defined as hemoglobin<12 or<13 g/dL in females and males, respectively. Additional iron and hematological indices were assessed in patients with FID. RESULTS: Prevalence of absolute- and functional-ID was 8.7 and 52.5%, respectively. Anemia was found in 11.2% of the cohort, 80% of which were associated with ID. Among patients with FID, transferrin saturation (T-Sat)<20% was common (70.0%) and associated with larger impairment of hematological indices. CONCLUSION: The data show that when hs-CRP as inflammatory marker and ferritin as iron index are considered, impaired iron status could be identified in approximately two thirds of BS candidates. Furthermore, T-Sat<20%, especially along with ferritin<30 ng/mL, appear to be practical cut-offs to identify patients with FID with larger iron status impairment.

Prospective study of individualized or high fixed doses of vitamin D supplementation after bariatric surgery.

BACKGROUND: The degree of bariatric surgery (BS) induced vitamin D (VD) malabsorption is not well established. OBJECTIVE: The aim of this study is to evaluate the efficacy and safety of achieving 25-hydroxy VD (25(OH)D) levels ≥75 nmol/L with two regimens of VD supplementation after BS. METHODS: We performed two open-label, prospective studies in patients undergoing BS from 2009 to 2011. Postoperatively, all patients received Ca citrate 1,000 mg and 800 IU of VD3/day. In the first study, additional VD3 was prescribed according to preoperative 25(OH)D levels- < 25 nmol/L:2,800 IU/day; 26-50 nmol/L:2,000-1,200 IU/day, 51-62 nmol/L:1,000 IU; >63 nmol/L:0 IU/day-and we evaluated the patients at baseline and at 4 months. In the second study, an additional fixed high dose of 2,000 IU/day of VD3 was administered, and we evaluated patients at baseline and at 4 and 12 months after BS. RESULTS: The first study included 176 patients [mean age 44 (11)]; 140 were females. Before BS, 171 subjects (98 %) presented 25(OH)D levels <75 nmol/L. Postoperatively, the mean 25(OH)D levels increased from 40 (17) to 77 nmol/L (29) (p < 0.001) with no differences in parathormone (PTH) or 25(OH)D levels between dose groups. In the second study, we enrolled 52 patients [mean age 45 (10)]; 32 were females. Postoperatively, the mean 25(OH)D levels increased from 32 (12) to 80 (22) and to 75 nmol/L (15) (p < 0.001) at 4 and 12 months, respectively. In both studies, a high percentage of patients achieved 25(OH)D ≥75 nmol/L levels and no subject reported any serious adverse event. CONCLUSIONS: Both schedules of daily VD3 supplementation were effective and safe under conditions of clinical practice.