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Extended follow-up of local steroid injection for carpal tunnel syndrome: A randomized clinical trial

Author/s: 
Hofer, M., Ranstam, J., Atroshi, I.

Importance Local steroid injection is commonly used in treating patients with idiopathic carpal tunnel syndrome, but evidence regarding long-term efficacy is lacking.

Objective To assess the long-term treatment effects of local steroid injection for carpal tunnel syndrome.

Design, Setting, and Participants This exploratory 5-year extended follow-up of a double-blind, placebo-controlled randomized clinical trial was conducted from November 2008 to March 2012 at a university hospital orthopedic department. Participants included patients aged 22 to 69 years with primary idiopathic carpal tunnel syndrome and no prior treatment with local steroid injections. Data were analyzed from May 2018 to August 2018.

Interventions Patients were randomized to injection of 80 mg methylprednisolone, 40 mg methylprednisolone, or saline.

Main Outcomes and Measures The coprimary outcomes were the symptom severity score and rate of subsequent carpal tunnel release surgery on the study hand at 5 years. Secondary outcomes were time from injection to surgical treatment, SF-36 bodily pain score, and score on the 11-item disabilities of the arm, shoulder, and hand scale.

Results A total of 111 participants (mean [SD] age at follow-up, 52.9 [11.6] years; 81 [73.0%] women and 30 [27.0%] men) were randomized, with 37 in the 80 mg methylprednisolone group, 37 in the 40 mg methylprednisolone group, and 37 in the saline placebo group. Complete 5-year follow-up data were obtained from all 111 participants with no dropouts (100% follow-up). At baseline, mean (SD) symptom severity scores were 2.93 (0.85) in the 80 mg methylprednisolone group, 3.13 (0.70) in the 40 mg methylprednisolone group, and 3.18 (0.75) in the placebo group, and at the 5-year follow up, mean (SD) symptom severity scores were 1.51 (0.66) in the 80 mg methylprednisolone group, 1.59 (0.63) in the 40 mg methylprednisolone group, and 1.67 (0.74) in the placebo group. Compared with placebo, there was no significant difference in mean change in symptom severity score from baseline to 5 years for the 80 mg methylprednisolone group (0.14 [95%CI, −0.17 to 0.45]) or the 40 mg methylprednisolone group (0.12 [95%CI, −0.19 to 0.43]). After injection, subsequent surgical treatment on the study hand was performed in 31 participants (83.8%) in the 80 mg methylprednisolone group, 34 participants (91.9%) in the 40 mg methylprednisolone group, and 36 participants (97.3%) in the placebo group; the number of participants who underwent surgical treatment between the 1-year and 5-year follow-ups was 4 participants (10.8%) in the 80 mg methylprednisolone group, 4 participants (10.8%) in the 40 mg methylprednisolone group, and 2 participants (5.4%) in the placebo group. All surgical procedures were conducted while participants and investigators were blinded to type of injection received. The mean (SD) time from injection to surgery was 180 (121) days in the 80 mg methylprednisolone group, 185 (125) days in the 40 mg methylprednisolone group, and 121 (88) days in the placebo group. Kaplan-Meier survival curves showed statistically significant difference in time to surgical treatment (log-rank test: 80 mg methylprednisolone vs placebo, P = .002 ; 40 mg methylprednisolone vs placebo, P = .02; methylprednisolone 80 mg vs 40 mg, P = .37).

Conclusions and Relevance These findings suggest that in idiopathic carpal tunnel syndrome, local methylprednisolone injection resulted in statistically significant reduction in surgery rates and delay in need for surgery.

Trial Registration ClinicalTrials.gov Identifiers: NCT00806871 and NCT02652390

Maintenance or Discontinuation of Antidepressants in Primary Care

Author/s: 
Lewis, G., Marston, L., Duffy, L., Freemantle, N., Gilbody, S., Hunter, R., Kendrick, T., Kessler, D., Mangin, D., King, M., Lanham, P., Moore, M.

BACKGROUND
Patients with depression who are treated in primary care practices may receive antidepressants for prolonged periods. Data are limited on the effects of maintaining or discontinuing antidepressant therapy in this setting.

METHODS
We conducted a randomized, double-blind trial involving adults who were being treated in 150 general practices in the United Kingdom. All the patients had a history of at least two depressive episodes or had been taking antidepressants for 2 years or longer and felt well enough to consider stopping antidepressants. Patients who had received citalopram, fluoxetine, sertraline, or mirtazapine were randomly assigned in a 1:1 ratio to maintain their current antidepressant therapy (maintenance group) or to taper and discontinue such therapy with the use of matching placebo (discontinuation group). The primary outcome was the first relapse of depression during the 52-week trial period, as evaluated in a time-to-event analysis. Secondary outcomes were depressive and anxiety symptoms, physical and withdrawal symptoms, quality of life, time to stopping an antidepressant or placebo, and global mood ratings.

RESULTS
A total of 1466 patients underwent screening. Of these patients, 478 were enrolled in the trial (238 in the maintenance group and 240 in the discontinuation group). The average age of the patients was 54 years; 73% were women. Adherence to the trial assignment was 70% in the maintenance group and 52% in the discontinuation group. By 52 weeks, relapse occurred in 92 of 238 patients (39%) in the maintenance group and in 135 of 240 (56%) in the discontinuation group (hazard ratio, 2.06; 95% confidence interval, 1.56 to 2.70; P<0.001). Secondary outcomes were generally in the same direction as the primary outcome. Patients in the discontinuation group had more symptoms of depression, anxiety, and withdrawal than those in the maintenance group.

CONCLUSIONS
Among patients in primary care practices who felt well enough to discontinue antidepressant therapy, those who were assigned to stop their medication had a higher risk of relapse of depression by 52 weeks than those who were assigned to maintain their current therapy. (Funded by the National Institute for Health Research; ANTLER ISRCTN number, ISRCTN15969819.)

Effect of 7 vs 14 Days of Antibiotic Therapy on Resolution of Symptoms Among Afebrile Men With Urinary Tract Infection: A Randomized Clinical Trial

Author/s: 
Drekonja, D. M., Trautner, B., Amundson, C.

Importance Determination of optimal treatment durations for common infectious diseases is an important strategy to preserve antibiotic effectiveness.

Objective To determine whether 7 days of treatment is noninferior to 14 days when using ciprofloxacin or trimethoprim/sulfamethoxazole to treat urinary tract infection (UTI) in afebrile men.

Design, Setting, and Participants Randomized, double-blind, placebo-controlled noninferiority trial of afebrile men with presumed symptomatic UTI treated with ciprofloxacin or trimethoprim/sulfamethoxazole at 2 US Veterans Affairs medical centers (enrollment, April 2014 through December 2019; final follow-up, January 28, 2020). Of 1058 eligible men, 272 were randomized.

Interventions Participants continued the antibiotic prescribed by their treating clinician for 7 days of treatment and were randomized to receive continued antibiotic therapy (n = 136) or placebo (n = 136) for days 8 to 14 of treatment.

Main Outcomes and Measures The prespecified primary outcome was resolution of UTI symptoms by 14 days after completion of active antibiotic treatment. A noninferiority margin of 10% was selected. The as-treated population (participants who took ≥26 of 28 doses and missed no more than 2 consecutive doses) was used for the primary analysis, and a secondary analysis included all patients as randomized, regardless of treatment adherence. Secondary outcomes included recurrence of UTI symptoms and/or adverse events within 28 days of stopping study medication.

Results Among 272 patients (median [interquartile range] age, 69 [62-73] years) who were randomized, 100% completed the trial and 254 (93.4%) were included in the primary as-treated analysis. Symptom resolution occurred in 122/131 (93.1%) participants in the 7-day group vs 111/123 (90.2%) in the 14-day group (difference, 2.9% [1-sided 97.5% CI, –5.2% to ∞]), meeting the noninferiority criterion. In the secondary as-randomized analysis, symptom resolution occurred in 125/136 (91.9%) participants in the 7-day group vs 123/136 (90.4%) in the 14-day group (difference, 1.5% [1-sided 97.5% CI, –5.8% to ∞]) Recurrence of UTI symptoms occurred in 13/131 (9.9%) participants in the 7-day group vs 15/123 (12.9%) in the 14-day group (difference, –3.0% [95% CI, –10.8% to 6.2%]; P = .70). Adverse events occurred in 28/136 (20.6%) participants in the 7-day group vs 33/136 (24.3%) in the 14-day group.

Conclusions and Relevance Among afebrile men with suspected UTI, treatment with ciprofloxacin or trimethoprim/sulfamethoxazole for 7 days was noninferior to 14 days of treatment with regard to resolution of UTI symptoms by 14 days after antibiotic therapy. The findings support the use of a 7-day course of ciprofloxacin or trimethoprim/sulfamethoxazole as an alternative to a 14-day course for treatment of afebrile men with UTI.

Trial Registration ClinicalTrials.gov identifier: NCT01994538

The effect of high-dose vitamin D supplementation on serum vitamin D levels and milk calcium concentration in lactating women and their infants

Author/s: 
Basile, L. A., Taylor, S. N., Wagner, C. L., Horst, R. L., Hollis, B. W.

Objective: Improve vitamin D status in lactating women and their recipient infants, and measure breast milk calcium concentration [Ca] as a function of vitamin D regimen.

Design/methods: Fully breastfeeding mothers were randomized at 1 month postpartum to 2000 (n = 12) or 4000 (n = 13) IU/day vitamin D for 3 months to achieve optimal vitamin D status [serum 25(OH)D > or =32 ng/mL (80 nmol/L)]. Breast milk [Ca], maternal and infant serum 25(OH)D and serum Ca, and maternal urinary Ca/Cr ratio were measured monthly.

Results: Mothers were similar between groups for age, race, gestation, and birth weight. 25(OH)D increased from 1 to 4 months in both groups (mean +/- SD): +11.5 +/- 2.3 ng/mL for group 2000 (p = 0.002) and +14.4 +/- 3.0 ng/mL for group 4000 (p = 0.0008). The 4000 IU/day regimen was more effective in raising both maternal and infant serum levels and breast milk antirachitic activity than the 2000 IU/day regimen. Breast milk [Ca] fell with continued lactation through 4 months in the 2000 and 4000 IU groups. Decline in breast milk [Ca] was not associated with vitamin D dose (p = 0.73) or maternal 25(OH)D (p = 0.94). No mother or infant experienced vitamin D-related adverse events, and all laboratory parameters remained in the normal range.

Conclusion: High-dose vitamin D was effective in increasing 25(OH)D levels in fully breastfeeding mothers to optimal levels without evidence of toxicity. Breast milk [Ca] and its decline in both groups during 1 to 4 months were independent of maternal vitamin D status and regimen. Both the mother and her infant attained improved vitamin D status and maintained normal [Ca].

Midodrine for the Prevention of Vasovagal Syncope : A Randomized Clinical Trial

Author/s: 
Sheldon, R., Faris, P., Tang, A., Ayala-Paredes, F., Guzman, J., Marquez, M., Morillo, C. A., Krahn, A. D., Kus, T., Ritchie, D., Safdar, S., Maxey, C., Raj, S. R.

Background: Recurrent vasovagal syncope is common, responds poorly to treatment, and causes physical trauma and poor quality of life. Midodrine prevents hypotension and syncope during tilt tests in patients with vasovagal syncope.

Objective: To determine whether midodrine can prevent vasovagal syncope in usual clinical conditions.

Design: Randomized, double-blind, placebo-controlled clinical trial. (ClinicalTrials.gov: NCT01456481).

Setting: 25 university hospitals in Canada, the United States, Mexico, and the United Kingdom.

Patients: Patients with recurrent vasovagal syncope and no serious comorbid conditions.

Intervention: Patients were randomly assigned 1:1 to placebo or midodrine and followed for 12 months.

Measurements: The primary outcome measure was the proportion of patients with at least 1 syncope episode during follow-up.

Results: The study included 133 patients who had had a median of 6 syncope episodes in the prior year (median age, 32 years; 73% female). Compared with patients receiving placebo, fewer patients receiving midodrine had at least 1 syncope episode (28 of 66 [42%] vs. 41 of 67 [61%]). The relative risk was 0.69 (95% CI, 0.49 to 0.97; P = 0.035). The absolute risk reduction was 19 percentage points (CI, 2 to 36 percentage points), and the number needed to treat to prevent 1 patient from having syncope was 5.3 (CI, 2.8 to 47.6). The time to first syncope was longer with midodrine (hazard ratio, 0.59 [CI, 0.37 to 0.96]; P = 0.035; log-rank P = 0.031). Adverse effects were similar in both groups.

Limitation: Small study size, young and healthy patients, relatively short observation period, and high proportion of patients from 1 center.

Conclusion: Midodrine can reduce the recurrence of syncope in healthy, younger patients with a high syncope burden."

Keywords 
Midodrine Vasovagal Syncope clinical trial prevention treatment

Once-Weekly Semaglutide in Adults with Overweight or Obesity

Author/s: 
Wilding, John P.H., Batterham, Rachel L., Calanna, Salvatore, Davies, Melanie, Van Gaal, Luc F., Lingvay, Ildiko, McGowan, Barbara M., Rosenstock, Julio, Tran, Marie T.D., Wadden, Thomas A.,, Sean, Yokote, Koutaro, Zeuthen, Niels, Kushner, Robert F., STEP 1 Study Group

Background: Obesity is a global health challenge with few pharmacologic options. Whether adults with obesity can achieve weight loss with once-weekly semaglutide at a dose of 2.4 mg as an adjunct to lifestyle intervention has not been confirmed.

Methods: In this double-blind trial, we enrolled 1961 adults with a body-mass index (the weight in kilograms divided by the square of the height in meters) of 30 or greater (≥27 in persons with ≥1 weight-related coexisting condition), who did not have diabetes, and randomly assigned them, in a 2:1 ratio, to 68 weeks of treatment with once-weekly subcutaneous semaglutide (at a dose of 2.4 mg) or placebo, plus lifestyle intervention. The coprimary end points were the percentage change in body weight and weight reduction of at least 5%. The primary estimand (a precise description of the treatment effect reflecting the objective of the clinical trial) assessed effects regardless of treatment discontinuation or rescue interventions.

Results: The mean change in body weight from baseline to week 68 was -14.9% in the semaglutide group as compared with -2.4% with placebo, for an estimated treatment difference of -12.4 percentage points (95% confidence interval [CI], -13.4 to -11.5; P<0.001). More participants in the semaglutide group than in the placebo group achieved weight reductions of 5% or more (1047 participants [86.4%] vs. 182 [31.5%]), 10% or more (838 [69.1%] vs. 69 [12.0%]), and 15% or more (612 [50.5%] vs. 28 [4.9%]) at week 68 (P<0.001 for all three comparisons of odds). The change in body weight from baseline to week 68 was -15.3 kg in the semaglutide group as compared with -2.6 kg in the placebo group (estimated treatment difference, -12.7 kg; 95% CI, -13.7 to -11.7). Participants who received semaglutide had a greater improvement with respect to cardiometabolic risk factors and a greater increase in participant-reported physical functioning from baseline than those who received placebo. Nausea and diarrhea were the most common adverse events with semaglutide; they were typically transient and mild-to-moderate in severity and subsided with time. More participants in the semaglutide group than in the placebo group discontinued treatment owing to gastrointestinal events (59 [4.5%] vs. 5 [0.8%]).

Conclusions: In participants with overweight or obesity, 2.4 mg of semaglutide once weekly plus lifestyle intervention was associated with sustained, clinically relevant reduction in body weight. (Funded by Novo Nordisk; STEP 1 ClinicalTrials.gov number, NCT03548935).

Keywords 
obesity Global Health overweight Semaglutide weight loss Life Style

Effect of Subcutaneous Semaglutide vs Placebo as an Adjunct to Intensive Behavioral Therapy on Body Weight in Adults With Overweight or Obesity: The STEP 3 Randomized Clinical Trial

Author/s: 
Wadden, Thomas A., Bailey, Timothy S., Billings, Liana K., Davies, Melanie, Frias, Juan P., Koroleva, Anna, Lingvay, Ildiko, O'Neil, Patrick M., Runino, Domenica M., Skovgaard, Dorthe, Wallenstein, Signe O.R., Garvey, W. TImothy, STEP 3 Investigators

Importance: Weight loss improves cardiometabolic risk factors in people with overweight or obesity. Intensive lifestyle intervention and pharmacotherapy are the most effective noninvasive weight loss approaches.

Objective: To compare the effects of once-weekly subcutaneous semaglutide, 2.4 mg vs placebo for weight management as an adjunct to intensive behavioral therapy with initial low-calorie diet in adults with overweight or obesity.

Design, setting, and participants: Randomized, double-blind, parallel-group, 68-week, phase 3a study (STEP 3) conducted at 41 sites in the US from August 2018 to April 2020 in adults without diabetes (N = 611) and with either overweight (body mass index ≥27) plus at least 1 comorbidity or obesity (body mass index ≥30).

Interventions: Participants were randomized (2:1) to semaglutide, 2.4 mg (n = 407) or placebo (n = 204), both combined with a low-calorie diet for the first 8 weeks and intensive behavioral therapy (ie, 30 counseling visits) during 68 weeks.

Main outcomes and measures: The co-primary end points were percentage change in body weight and the loss of 5% or more of baseline weight by week 68. Confirmatory secondary end points included losses of at least 10% or 15% of baseline weight.

Results: Of 611 randomized participants (495 women [81.0%], mean age 46 years [SD, 13], body weight 105.8 kg [SD, 22.9], and body mass index 38.0 [SD, 6.7]), 567 (92.8%) completed the trial, and 505 (82.7%) were receiving treatment at trial end. At week 68, the estimated mean body weight change from baseline was -16.0% for semaglutide vs -5.7% for placebo (difference, -10.3 percentage points [95% CI, -12.0 to -8.6]; P < .001). More participants treated with semaglutide vs placebo lost at least 5% of baseline body weight (86.6% vs 47.6%, respectively; P < .001). A higher proportion of participants in the semaglutide vs placebo group achieved weight losses of at least 10% or 15% (75.3% vs 27.0% and 55.8% vs 13.2%, respectively; P < .001). Gastrointestinal adverse events were more frequent with semaglutide (82.8%) vs placebo (63.2%). Treatment was discontinued owing to these events in 3.4% of semaglutide participants vs 0% of placebo participants.

Conclusions and relevance: Among adults with overweight or obesity, once-weekly subcutaneous semaglutide compared with placebo, used as an adjunct to intensive behavioral therapy and initial low-calorie diet, resulted in significantly greater weight loss during 68 weeks. Further research is needed to assess the durability of these findings.

Keywords 
weight loss body mass index BMI body weight obesity

Bupropion and Naltrexone in Methamphetamine Use Disorder

Author/s: 
Trivedi, Madhukar H., Walker, Robrina, Ling, Walter, Dela Cruz, Adriane, Sharma, Gaurav, Carmody, Thomas, Ghitza, Udi E., Wahle, Aimee, Kim, Mora, Shores-Wilson, Kathy, Sparenborg, Steven, Coffin, Philip, Schmitz, Joy, Wiest, Katharina, Bart, Gavin, Sonne, Susan C., Wakhlu, Sidarth, Rush, A.J., Nunes, Edward V., Shoptaw, Steven

BACKGROUND

The use of naltrexone plus bupropion to treat methamphetamine use disorder has not been well studied.

METHODS

We conducted this multisite, double-blind, two-stage, placebo-controlled trial with the use of a sequential parallel comparison design to evaluate the efficacy and safety of extended-release injectable naltrexone (380 mg every 3 weeks) plus oral extended-release bupropion (450 mg per day) in adults with moderate or severe methamphetamine use disorder. In the first stage of the trial, participants were randomly assigned in a 0.26:0.74 ratio to receive naltrexone–bupropion or matching injectable and oral placebo for 6 weeks. Those in the placebo group who did not have a response in stage 1 underwent rerandomization in stage 2 and were assigned in a 1:1 ratio to receive naltrexone–bupropion or placebo for an additional 6 weeks. Urine samples were obtained from participants twice weekly. The primary outcome was a response, defined as at least three methamphetamine-negative urine samples out of four samples obtained at the end of stage 1 or stage 2, and the weighted average of the responses in the two stages is reported. The treatment effect was defined as the between-group difference in the overall weighted responses.

RESULTS

A total of 403 participants were enrolled in stage 1, and 225 in stage 2. In the first stage, 18 of 109 participants (16.5%) in the naltrexone–bupropion group and 10 of 294 (3.4%) in the placebo group had a response. In the second stage, 13 of 114 (11.4%) in the naltrexone–bupropion group and 2 of 111 (1.8%) in the placebo group had a response. The weighted average response across the two stages was 13.6% with naltrexone–bupropion and 2.5% with placebo, for an overall treatment effect of 11.1 percentage points (Wald z-test statistic, 4.53; P<0.001). Adverse events with naltrexone–bupropion included gastrointestinal disorders, tremor, malaise, hyperhidrosis, and anorexia. Serious adverse events occurred in 8 of 223 participants (3.6%) who received naltrexone–bupropion during the trial.

CONCLUSIONS

Among adults with methamphetamine use disorder, the response over a period of 12 weeks among participants who received extended-release injectable naltrexone plus oral extended-release bupropion was low but was higher than that among participants who received placebo. 

Keywords 
Methamphetamine Use Disorder Bupropion naltrexone

REGN-COV2, a Neutralizing Antibody Cocktail, in Outpatients with Covid-19

Author/s: 
Weinreich, David M., Sivapalasingam, Sumathi, Norton, THomas,, Ali, Shazia, Gao, Haitao, Bhore, Rafia, Musser, Bret J., Soo, Yuhwen, Rofail, Diana, Im, Joseph, Perry, Christina, Pan, Cynthia, Hosain, Romana, Mahmood, Adnan, Davis, John D., Turner, Kenneth C., Hooper, Andrea T., Hamilton, Jennifer D., Baum, Alina, Kyratsous, Christos A., Kim, Yunji, Cook, Amanda, Kampman, Wendy, Kohli, Anita, Sachdeva. Yessica, Graber, Ximena, Kowal, Bari, DiCioccio, Thomas, Stahl, Neil, Lipsich, Leah, Braunstein, Ned, Herman, Gary, Yancopoulos, George D.

Background: Recent data suggest that complications and death from coronavirus disease 2019 (Covid-19) may be related to high viral loads.

Methods: In this ongoing, double-blind, phase 1-3 trial involving nonhospitalized patients with Covid-19, we investigated two fully human, neutralizing monoclonal antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein, used in a combined cocktail (REGN-COV2) to reduce the risk of the emergence of treatment-resistant mutant virus. Patients were randomly assigned (1:1:1) to receive placebo, 2.4 g of REGN-COV2, or 8.0 g of REGN-COV2 and were prospectively characterized at baseline for endogenous immune response against SARS-CoV-2 (serum antibody-positive or serum antibody-negative). Key end points included the time-weighted average change from baseline in viral load from day 1 through day 7 and the percentage of patients with at least one Covid-19-related medically attended visit through day 29. Safety was assessed in all patients.

Results: Data from 275 patients are reported. The least-squares mean difference (combined REGN-COV2 dose groups vs. placebo group) in the time-weighted average change in viral load from day 1 through day 7 was -0.56 log10 copies per milliliter (95% confidence interval [CI], -1.02 to -0.11) among patients who were serum antibody-negative at baseline and -0.41 log10 copies per milliliter (95% CI, -0.71 to -0.10) in the overall trial population. In the overall trial population, 6% of the patients in the placebo group and 3% of the patients in the combined REGN-COV2 dose groups reported at least one medically attended visit; among patients who were serum antibody-negative at baseline, the corresponding percentages were 15% and 6% (difference, -9 percentage points; 95% CI, -29 to 11). The percentages of patients with hypersensitivity reactions, infusion-related reactions, and other adverse events were similar in the combined REGN-COV2 dose groups and the placebo group.

Conclusions: In this interim analysis, the REGN-COV2 antibody cocktail reduced viral load, with a greater effect in patients whose immune response had not yet been initiated or who had a high viral load at baseline. Safety outcomes were similar in the combined REGN-COV2 dose groups and the placebo group. 

Keywords 
COVID-19 COVID-19 vaccine SARS coronavirus SARS-CoV-2 Antibodies coronavirus

Effect of Vitamin D3 Supplements on Development of Advanced Cancer: A Secondary Analysis of the VITAL Randomized Clinical Trial

Author/s: 
Chandler, P.D., Chen, W.Y., Ojala, O.N.

Importance  Epidemiologic and trial data suggest that vitamin D supplementation may reduce metastatic cancer and cancer mortality, reflecting shared biological pathways.

Objective  To follow up on the possible reduction in cancer death in the Vitamin D and Omega-3 Trial (VITAL) with an evaluation of whether vitamin D reduces the incidence of advanced (metastatic or fatal) cancer and an examination possible effect modification by body mass index.

Design, Setting, and Participants  VITAL is a randomized, double-blind, placebo-controlled, 2 × 2 factorial clinical trial of vitamin D3 (cholecalciferol, 2000 IU/d) and marine omega-3 fatty acids (1 g/d). This multicenter clinical trial was conducted in the United States; participants included men aged 50 years or older and women aged 55 years or older who were free of cancer and cardiovascular disease at baseline. Randomization took place from November 2011 through March 2014, and study medication ended on December 31, 2017. Data for this secondary analysis were analyzed from November 1, 2011, to December 31, 2017.

Interventions  Vitamin D3 (cholecalciferol, 2000 IU/d) and marine omega-3 fatty acids (1 g/d) supplements.

Main Outcomes and Measures  For the present analysis, the primary outcome was a composite incidence of metastatic and fatal invasive total cancer, because the main VITAL study showed a possible reduction in fatal cancer with vitamin D supplementation and effect modification by body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) for total cancer incidence reduction for individuals with normal BMI, but not for individuals with overweight or obesity. Secondary analyses included examination of BMI (<25, 25 to < 30, and ≥30) as effect modifiers of the observed associations.

Results  Among 25 871 randomized VITAL participants (51% female; mean [SD] age, 67.1 [7.1] years), 1617 were diagnosed with invasive cancer over a median intervention period of 5.3 years (range, 3.8-6.1 years). As previously reported, no significant differences for cancer incidence by treatment arm were observed. However, a significant reduction in advanced cancers (metastatic or fatal) was found for those randomized to vitamin D compared with placebo (226 of 12 927 assigned to vitamin D [1.7%] and 274 of 12 944 assigned to placebo [2.1%]; HR, 0.83 [95% CI, 0.69-0.99]; P = .04). When stratified by BMI, there was a significant reduction for the vitamin D arm in incident metastatic or fatal cancer among those with normal BMI (BMI<25: HR, 0.62 [95% CI, 0.45-0.86]) but not among those with overweight or obesity (BMI 25-<30: HR, 0.89 [95% CI, 0.68-1.17]; BMI≥30: HR, 1.05 [95% CI, 0.74-1.49]) (P = .03 for interaction by BMI).

Conclusions and Relevance  In this randomized clinical trial, supplementation with vitamin D reduced the incidence of advanced (metastatic or fatal) cancer in the overall cohort, with the strongest risk reduction seen in individuals with normal weight.

Trial Registration  ClinicalTrials.gov Identifier: NCT01169259

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