Vitamin D3 supplementation in patients with frequent respiratory tract infections: a randomised and double-blind intervention study Prevention of urinary tract infections with vitamin D supplementation 20,000 IU per week for five years. Results from an RCT including 511 subjects Association between serum 25-hydroxyvitamin D level and upper respiratory tract infection in the Third National Health and Nutrition Examination Survey. Low Serum 25-Hydroxyvitamin D Level and Risk of Upper Respiratory Tract Infection in Children and Adolescents A cluster-randomised controlled trial to test the efficacy of facemasks in preventing respiratory viral infection among Hajj pilgrims Regular vitamin C supplementation during pregnancy reduces hospitalization: outcomes of a Ugandan rural cohort study Ceftriaxone versus Other Antibiotics for Surgical Prophylaxis Efficacy of vitamin D supplementation in depression in adults: a systematic review protocol Efficacy of a polyvalent bacterial lysate in children with recurrent respiratory tract infections Prebiotic and probiotic supplementation prevents rhinovirus infections in preterm infants: A randomized, placebo-controlled trial 158 Efficacy of Immnunotherapy with an Oral Bacterial Lysate and Vitamin C in the Primary Prevention of Acute Respiratory Tract Infections in Children Hospitalization for Lower Respiratory Tract Disease in Preterm Infants: Effects of Prophylaxis with Palivizumab Does homeopathic medicine have a preventive effect on respiratory tract infections? A real life observational study Three-Year Study of Viral Etiology and Features of Febrile Respiratory Tract Infections in Japanese Pediatric Outpatients Occurrence of Community-Acquired Respiratory Tract Infection in Patients Receiving Esomeprazole Effect of daily vitamin E and multivitamin-mineral supplementation on acute respiratory tract infections in elderly persons: a randomized controlled trial. A randomized controlled trial of vitamin D3 supplementation for the prevention of symptomatic upper respiratory tract infections. Efficacy of oral immunotherapy on respiratory infections in hemodialysis patients: a double-blind, placebo-controlled study.
Background Low serum levels of 25-hydroxyvitamin D3 are associated with an increased risk of respiratory tract infections ( RTIs ) . Clinical trials with vitamin D3 against various infections have been carried out but data are so far not conclusive . Thus , there is a need for additional r and omised controlled trials of effects of vitamin D3 on infections . Objective To investigate if supplementation with vitamin D3 could reduce infectious symptoms and antibiotic consumption among patients with antibody deficiency or frequent RTIs . Design A double-blind r and omised controlled trial . Setting Karolinska University Hospital , Huddinge . Participants 140 patients with antibody deficiency ( selective IgA subclass deficiency , IgG subclass deficiency , common variable immune disorder ) and patients with increased susceptibility to RTIs ( > 4 bacterial RTIs/year ) but without immunological diagnosis . Intervention Vitamin D3 ( 4000 IU ) or placebo was given daily for 1 year . Primary and secondary outcome measures The primary endpoint was an infectious score based on five parameters : symptoms from respiratory tract , ears and sinuses , malaise and antibiotic consumption . Secondary endpoints were serum levels of 25-hydroxyvitamin D3 , microbiological findings and levels of antimicrobial peptides ( LL-37 , HNP1–3 ) in nasal fluid . Results The overall infectious score was significantly reduced for patients allocated to the vitamin D group ( 202 points ) compared with the placebo group ( 249 points ; adjusted relative score 0.771 , 95 % CI 0.604 to 0.985 , p=0.04 ) . Limitations A single study centre , small sample size and a selected group of patients . The sample size calculation was performed using p=0.02 as the significance level whereas the primary and secondary endpoints were analysed using the conventional p=0.05 as the significance level . Conclusions Supplementation with vitamin D3 may reduce disease burden in patients with frequent RTIs Abstract Background : In observational studies vitamin D deficiency is associated with increased risk of infections , whereas the effect of vitamin D supplementation in r and omized controlled trials is non-conclusive . Methods : Five hundred and eleven subjects with prediabetes were r and omized to vitamin D3 ( 20,000 IU per week ) versus placebo for five years . Every sixth month , a question naire on respiratory tract infections ( RTI ) ( common cold , bronchitis , influenza ) and urinary tract infection ( UTI ) was filled in . Results : Mean baseline serum 25-hydroxyvitamin D ( 25(OH)D ) level was 60 nmol/L. Two hundred and fifty-six subjects received vitamin D and 255 placebo . One hundred and sixteen subjects in the vitamin D and 111 in the placebo  group completed the five-year study . Eighteen subjects in the vitamin D group and 34 subjects in the placebo group reported UTI during the study ( p < 0.02 ) , whereas no significant differences were seen for RTI . The effect on UTI was most pronounced in males . The effect of vitamin D on UTI was unrelated to baseline serum 25(OH)D level . Conclusion : Supplementation with vitamin D might prevent UTI , but confirmatory studies are needed BACKGROUND Recent studies suggest a role for vitamin D in innate immunity , including the prevention of respiratory tract infections ( RTIs ) . We hypothesize that serum 25-hydroxyvitamin D ( 25[OH]D ) levels are inversely associated with self-reported recent upper RTI ( URTI ) . METHODS We performed a secondary analysis of the Third National Health and Nutrition Examination Survey , a probability survey of the US population conducted between 1988 and 1994 . We examined the association between 25(OH)D level  and  recent URTI in 18 883 participants 12 years and older . The analysis adjusted for demographics and clinical factors ( season , body mass index , smoking history , asthma , and chronic obstructive pulmonary disease ) . RESULTS The median serum 25(OH)D level was 29 ng/mL ( to convert to nanomoles per liter , multiply by 2.496 ) ( interquartile range , 21 - 37 ng/mL ) , and 19 % ( 95 % confidence interval [ CI ] , 18%-20 % ) of participants reported a recent URTI . Recent URTI was reported by 24 % of participants with 25(OH)D levels less than 10 ng/mL , by 20 % with levels of 10 to less than 30 ng/mL , and by 17 % with levels of 30 ng/mL or more ( P < .001 ) . Even after adjusting for demographic and clinical characteristics , lower 25(OH)D levels were independently associated with recent URTI ( compared with 25[OH]D levels of > or = 30 ng/mL : odds ratio [ OR ] , 1.36 ; 95 % CI , 1.01 - 1.84 for < 10 ng/mL and 1.24 ; 1.07 - 1.43 for 10 to < 30 ng/mL ) . The association between 25(OH)D level and URTI seemed to be stronger in individuals with asthma and chronic obstructive pulmonary disease ( OR , 5.67 and 2.26 , respectively ) . CONCLUSIONS Serum 25(OH)D levels are inversely associated with recent URTI . This association may be stronger in those with respiratory tract diseases . R and omized controlled trials are warranted to explore the effects of vitamin D supplementation on RTI Respiratory tract infections ( RTIs ) are very common worldwide . We prospect ively demonstrate an association between low serum 25-hydroxyvitamin D level and increased risk of laboratory-confirmed viral upper RTI  in children . Future studies should evaluate the role of supplementation to reduce RTIs Abstract Background Cost-effective interventions are needed to control the transmission of viral respiratory tract infections ( RTIs ) in mass gatherings . Facemasks are a promising preventive measure , however , previous studies on the efficacy of facemasks have been inconclusive . This study proposes a large-scale facemask trial during the Hajj pilgrimage in Saudi Arabia and presents this protocol to illustrate its feasibility and to promote both collaboration with other research groups and additional relevant studies . Methods / design A cluster-r and omised controlled trial is being conducted to test the efficacy of st and ard facemasks in preventing symptomatic and proven viral RTIs among pilgrims during the Hajj season in Mina , Mecca , Saudi Arabia . The trial will compare the ‘ supervised use of facemasks ’ versus ‘ st and ard measures ’ among pilgrims over several Hajj seasons . Cluster-r and omisation will be done by accommodation tents with a 1:1 ratio . For the intervention tents , free facemasks will be provided to be worn consistently for 7days . Data on flu-like symptoms and mask use will be recorded in diaries . Nasal sample s will be collected from symptomatic recruits and tested for nucleic acid of respiratory viruses . Data obtained from question naires , diaries and laboratory tests will be analysed to examine whether mask use significantly reduces the frequency of laboratory-confirmed respiratory viral infection and syndromic RTI as primary outcomes . Conclusions This trial will provide valuable evidence on the efficacy of st and ard facemask use in preventing viral respiratory tract infections at mass gatherings . This study is registered at the Australian New Zeal and Clinical Trials Registry ( ANZCTR ) , ACTRN : ACTRN12613001018707 ( http://www.anzctr.org.au ) Background Vitamin C or ascorbic acid is a hydro-soluble lactone ( synthesized from glucose ) essential to human body and available from diet . Despite its broad availability in fruits and vegetables , in many developing countries the incidence of clinical symptoms due to the vitamin deficiency is still very high . Also , pregnant women in the developing countries are frequently hospitalized for several preventable reasons such as anemia in pregnancy , mostly iron-deficient anemia ( IDA ) and the upper/lower respiratory tract infections ( RTI ) . The aim of the study was to investigate , in a Ug and an rural pregnant women cohort , the preventive effects of vitamin C supplementation on hospital admission . Methods 384 pregnant women met the inclusion criteria and were r and omly assigned to receive either 400 mg of vitamin C daily ( 187 ) or not ( 197 ) in addition to their st and ard antenatal vitamins until delivery . The primary outcome measure of this study was to assess the prevention of hospitalization during pregnancy in the group of women supplemented with vitamin C compared to the controls . Fisher‘s exact test was employed in this assessment . Results 42.2 % women in the vitamin C group and 27.9 % in the control group were not hospitalized during pregnancy ; this difference was found statistically significant . Conclusion The results of this study suggest including vitamin C in the guidelines of multivitamin prevention for pregnant women , especially in developing countries where seasonal availability of fruits and vegetables could result in adverse clinical outcomes Objective To investigate possible differences in prophylaxis with ceftriaxone compared with other antimicrobial agents for  surgical-site infections and remote infections such as respiratory tract infections ( RTIs ) and urinary tract infections ( UTIs ) . Methods The efficacy of ceftriaxone was compared with that of other antibiotics in the perioperative prophylaxis of local ( surgical wound ) and remote ( RTIs and UTIs ) infections  in a meta- analysis of r and omised controlled trials published between 1984 and 2003 . The analysis was based on a 2 × 2 contingency table with classification by treatment and number of infections obtained from individual studies . Results Evaluations were performed on 48 studies , for a total of 17 565 patients . Overall , 406 patients ( 4.8 % ) in the ceftriaxone group and 525 ( 6.3 % ) in the comparator group developed a surgical-site infection ( log odds ratio [ OR ] −0.30 [ CI −0.50 to −0.13 ] ; p < 0.0001 ) . RTIs were observed in 292 ( 6.01 % ) patients in the ceftriaxone group and in 369 ( 7.6 % ) patients in the comparator group , ( log OR −0.30 [ CI −0.55 to −0.09 ] ; p = 0.0013 ) . UTIs were reported for 2.2 % of the ceftriaxone prophylaxis patients compared with 3.74 % of the comparator group patients ( log OR −0.54 [ CI −1.18 to −0.16 ] ; p < 0.0001 ) . Overall , in clean surgery 195 ( 5.1 % ) and 234 ( 6.2 % ) patients developed a surgical site infection in the ceftriaxone and comparator groups , respectively ( log OR −0.22 [ CI −0.51 to 0.01 ] ; p = 0.0476 ) . RTIs were prevented for all but 1.57 % of patients in the ceftriaxone group and 2.62 % of patients in the comparator group ( p = 0.01 ) in clean surgery , and for 9.54 % of the ceftriaxone group versus 11.6 % of the comparator group ( p = 0.01 ) in clean-contaminated surgery . While results observed in clean surgery did not show statistically significant superiority of ceftriaxone in preventing UTI insurgence ( log OR −0.21 [ CI 0.0–0.65 ] ; p = 0.7702 ) , this was clearly shown in the clean-contaminated surgery . In fact , 4.47 % of patients in the ceftriaxone group versus 7.52 % of patients in the comparator group developed a UTI ( log OR −0.56 [ CI −1.25 to −0.16 ] ; p < 0.0001 ) . Adverse events were observed in a similar proportion in the ceftriaxone prophylaxis and the comparator groups ( 0.35 % and 0.23 % , respectively ) . Duration of prophylaxis did not influence outcome of infection . Conclusions The meta- analysis showed that ceftriaxone is statistically superior to other antibiotics in preventing both local and remote postoperative infections Background The role of vitamin D in management of depression is unclear . Results from observational and emerging r and omized controlled trials ( RCTs ) investigating the efficacy of vitamin D in depression lack consistency - with some suggesting a positive association while others show a negative or inconclusive association . Methods / Design The primary aim of this study is to conduct a systematic review of RCTs to assess the effect of oral vitamin D supplementation versus placebo on depression symptoms measured by scales and the proportion of patients with symptomatic improvement according to the authors ’ original definition . Secondary aims include assessing the change in quality of life , adverse events and treatment discontinuation . We will conduct the systematic review and meta- analysis according to the recommendations of the Cochrane H and book for Systematic Review s of Interventions . We will search the Cochrane Central Register of Controlled Trials ( CENTRAL ) , MEDLINE ( 1966 to present ) , EMBASE ( 1980 to present ) , CINAHL ( 1982 to present ) , PsychINFO ( 1967 to present ) and Clinical Trials.gov . Unpublished work will be identified by search ing two major conferences : the International Vitamin Conference , the Anxiety Disorders and Depression Conference , while grey literature will be acquired by contacting authors of included studies . We will use the r and om-effects meta- analysis to synthesize the data by pooling the results of included studies . Discussion The results of this systematic review will be helpful in clarifying the efficacy of vitamin D supplementation and providing evidence to establish guidelines for implementation of vitamin D for depression in general practice and other relevant setting s. Study registration Unique identifier : CRD42013003849 Respiratory tract infections ( RTIs ) are the most frequent infections in humans , particularly in children . In addition to intervention , increasing interest is focusing on immunomodulatory therapy for recurrent RTIs , which indicate a reduced defense capacity of the respiratory mucosa . LW 50020 , an oral immunomodulator that contains the antigens of seven bacteria common in RTIs , has reduced the number , duration , and severity of RTIs in children and adults . This 56-week placebocontrolled , double-blind study in 188 children investigated whether the efficacy of the st and ard schedule ( immunization cycle + one booster cycle ) would be enhanced by additional booster cycles . Efficacy and safety over the long term were also assessed . The rate of infection was reduced by 50 % with the st and ard schedule and could not be further decreased by two consecutive booster cycles . With both schedules , this reduction was sustained during a 28-week treatmentfree observation period that followed the 28-week treatment period . The number of adverse drug reactions was low , and all were transient , expected , and nonserious . These results confirm that LW 50020 is an effective and safe strategy for RTIs Background Simple and safe strategies for the prevention of viral respiratory tract infections ( RTIs )  are needed . Objective We hypothesized that early prebiotic or probiotic supplementation would reduce the risk of virus-associated RTIs during the first year of life in a cohort of preterm infants . Methods In this r and omized , double-blind , placebo-controlled trial ( Clinical Trials.gov no. NCT00167700 ) , 94 preterm infants ( gestational age , ≥32 + 0 and ≤36 + 6 weeks ; birth weight , > 1500 g ) treated at Turku University Hospital , Turku , Finl and , were allocated to receive oral prebiotics ( galacto-oligosaccharide and polydextrose mixture , 1:1 ) , a probiotic ( Lactobacillus rhamnosus GG , ATCC 53103 ) , or placebo ( microcrystalline cellulose ) between days 3 and 60 of life . The primary outcome was the incidence of clinical ly defined virus-associated RTI episodes confirmed from nasal swabs by using nucleic acid testing . Secondary outcomes were the severity and duration of RTIs . Results A significantly lower incidence of RTIs was detected in infants receiving prebiotics  ( rate ratio [ RR ] , 0.24 ; 95 % CI , 0.12 - 0.49 ; P < .001 ) or probiotics ( RR , 0.50 ; 95 % CI , 0.28 - 0.90 ; P = .022 ) compared with those receiving placebo . Also , the incidence of rhinovirus-induced episodes , which comprised 80 % of all RTI episodes , was found to be significantly lower in the prebiotic ( RR , 0.31 ; 95 % CI , 0.14 - 0.66 ; P = .003 ) and probiotic ( RR , 0.49 ; 95 % CI , 0.24 - 1.00 ; P = .051 ) groups compared with the placebo group . No differences emerged among the study groups in rhinovirus RNA load during infections , duration of rhinovirus RNA shedding , duration or severity of rhinovirus infections , or occurrence of rhinovirus RNA in asymptomatic infants . Conclusions Gut microbiota modification with specific prebiotics and probiotics might offer a novel and cost-effective means to reduce the risk of rhinovirus infections Background Airway infections are of great importance worldwide and nearly half of the pediatric consultations in industrialized countries are caused by respiratory tract infections ( RTIs ) . Acute respiratory tract infections ( ARTIs ) are among the main causes of morbidity and mortality in children and recurrent infections of the respiratory tract are the most frequent cause of pharmacotherapy in pediatric practice . The aim of this study was to evaluate the efficacy and tolerability of immunotherapy with oral bacterial lysates + vitamin C in the prevention of ARTIs in children . Methods 109 children with ages between 4 and 16 years with frequent respiratory tract infections ( 2–5 infections the previous winter ) were evaluated . Participants were r and omly allocated in 2 groups : 52 patients ( mean age 6.8 ± 2.9 years ; 20 males 32 females ) received no preventive therapy ( NPT group ) and 57 ( mean age 9.0 ± 3.3 years ; males 36 females 21 ) received immunotherapy with oral bacterial lysates + vitamin C ( VC group ) at the recommended dosage . Patients were followed up for 6 months , including the administration period . Primary end points were the type and number of ARTIs . Secondary end points ( after the infection occured ) included : time to clinical cure , severity of infection , absenteeism from school due to an ARTI , number of antibiotic courses or other drugs prescribed , and duration of concomitant drug treatment . Results There were significant differences between groups in the cumulative number of acute infectious episodes : 170 in NPT group ( 141 upper ARTIs , 29 lower ARTI , and 26 otitis episodes ) vs 55 in VC group ( 50 upper ARTIs , 5 lower ARTI and 4 otitis episodes ) . Patients in the NPT group received 127 antibiotic courses compared to 28 in the VC group ( P < 0.0001 ) . Patients in the NPT group had 475 days of absenteeism from school compared to 100 days in the VC group ( P < 0.0001 ) . No adverse events related to the trial medications were reported . Conclusions Immunotherapy with oral bacterial lysates and vitamin C appears to be very effective in the prevention of infectious episodes in pediatric patients with frequent respiratory tract infections . Future studies are needed to further explore the role of oral bacteroial lysates in ARTIs prevention Abstract To evaluate the effect of palivizumab prophylaxis on hospitalization for acute respiratory tract infections ( RTI ) in preterm infants , a prospect i ve study was performed on a cohort of preterm infants [ gestational age ( GA ) ≤32weeks ] , admitted at birth to a Neonatology Intensive Care Unit ( NICU ) ( follow-up : 30-month after discharge ) . 154 palivizumab-recipients and 71 palivizumab-non-recipients were evaluated . During follow-up , a similar rate of hospitalization for RTI was found in the two groups ( 11.3 % in palivizumab-non-recipients and 15.58 % in palivizumab-recipients , P=0.39 ) . However , when only infants hospitalized during their first respiratory syncytial virus ( RSV ) epidemic season and with a chronological age < 6 months at admission were considered , the incidence rates for hospitalization was six-fold lower in the palivizumab-recipients ( P=0.007 ) . This study contributes to the definition of epidemiological data on RTI among preterm infants in Italy . These data support the usefulness of palivizumab prophylaxis for prevention of hospitalization for RTI in young preterm infants during the expected RSV epidemic season Background Homeopathic medicine is a branch of integrative medicine that has been gaining increasing popularity . However , its clinical application remains controversial . To improve the underst and ing of homeopathy , observational studies -which monitor the effects of homeopathy in real-life clinical setting s-are a helpful adjunct to r and omized controlled trials . The goal of this controlled observational study was to investigate the role of the homeopathic medicine in preventing respiratory tract infections ( RTIs ) . Methods This retrospective analysis of patients ’ medical records focused on a single centre from 2002 to 2011 , and examined 459 patients , out of whom 248 were treated with homeopathic medicine ( specific extract of duck liver and heart ) and 211 were not treated .  All patients were followed-up for at least 1 year , and up to a maximum of 10 years . Results A significant reduction in the frequency of onset of RTIs was found in both the homeopathic medicine and untreated groups . The reduction in the mean number of RTI episodes during the period of observation vs. the year before inclusion in the study was significantly greater in the homeopathic-treated group than in untreated patients ( -4.76 ± 1.45 vs. -3.36 ± 1.30 ; p = 0.001 ) . The beneficial effect of the homeopathic medicine was not significantly related to gender , age , smoking habits or concomitant respiratory diseases when compared to the effect observed in untreated patients . Conclusion These results suggest that homeopathic medicine may have a positive effect in preventing RTIs . However , r and omized studies are needed before any firm conclusion can be reached Background : For most febrile respiratory tract infections ( RTIs ) in children , the causative pathogen is never identified . We sought to identify the causative pathogen in individual cases of pediatric outpatient with RTIs and to determine whether particular clinical features of RTIs are associated with particular viruses . Methods : Over 3 years , we prospect ively collected nasopharyngeal aspirate specimens from individual pediatric out patients with an RTI accompanied by persistent fever ( > 3 days , ≥38.0 ° C ) and peak temperature ≥39.0 ° C . Two methods —(1 ) viral culture for respiratory viruses and ( 2 ) real-time polymerase chain reaction ( PCR ) assays identifying 9 different respiratory viruses and 2 respiratory bacteria — were used to test specimens . Results : For 495 specimens , viral culture and real-time PCR assays together identified at least 1 pathogen in 83.0 % and ≥1 viruses alone in 79.4 % . These 2 methods identified 138 children with respiratory syncytial virus , 66 with human metapneumovirus , 73 with parainfluenza viruses , 124 with adenovirus , 23 with rhinovirus , 38 with enterovirus , 11 with influenza type C virus , 15 with Mycoplasma pneumoniae and 3 with Chlamydophila pneumoniae ; the coinfection rate was 19.7 % among all infections . Among the patients with single-pathogen infections , the rate of lower RTI was 37.6 % for respiratory syncytial virus , 40.7 % for human metapneumovirus , 18.2 % for parainfluenza viruses and 2.2 % for adenovirus ( P < 0.01 ) . Conclusions : Viral culture and real-time PCR assays were used together to identify causative pathogens in 83 % of febrile outpatient children with RTI ; specific viruses were associated with particular clinical diagnoses Abstract Background : A potential causal association between an increase in gastric pH and a risk of community-acquired respiratory tract infection ( RTI ) , specifically pneumonia , has been debated in relation to the use of potent gastric acid-suppressive medication . Objective : To investigate the occurrence of community-acquired RTI , including pneumonia , in patients receiving esomeprazole versus placebo and other acid-suppressive agents in r and omized clinical trials . Methods : The AstraZeneca ARIADNE safety data base was search ed for comparative , controlled phase II – IV r and omized , blinded clinical studies with esomeprazole and st and ard reporting of all adverse events ( AEs ) . Pooled AE data were presented according to treatment comparison ( esomeprazole versus placebo , esomeprazole 40 mg versus 20 mg daily , esomeprazole versus omeprazole , lansoprazole and /or ranitidine , respectively ) . Frequency and relative risk ( RR ) , with 99 % confidence interval ( CI ) and adjustment for time on treatment , were calculated for the following four AE categories : all RTIs ; signs and symptoms potentially indicating RTI ; lower RTI ; and pneumonia . Results : Thirty-one studies were identified , in which 16 583 patients received esomeprazole and 12 044 patients received either placebo or comparator acid-suppressive drugs . The occurrence of all four categories of AEs was similar between esomeprazole and placebo ( all RTIs : 9.2 % versus 8.5 % ; signs and symptoms of RTI : 1.8 % versus 1.8 % ; lower RTI : 1.6 % versus 1.5 % ; and pneumonia : 0.2 % in both groups ) . The RR estimates were as follows : all RTIs , 0.93 ( 99 % CI 0.78 , 1.11 ) ; signs and symptoms of RTI , 0.85 ( 99 % CI 0.57 , 1.27 ) ; lower RTI , 0.92 ( 99 % CI 0.59 , 1.42 ) ; and pneumonia , 0.94 ( 99 % CI 0.29 , 3.07 ) . The distribution of RTIs by patient sex and age showed a similar pattern in esomeprazole and placebo-treated patients . The comparisons of esomeprazole with the other comparator acid-suppressive drugs showed a similar pattern with only minor numerical differences in the occurrence of RTI between the drugs . There were no significant between-group differences with esomeprazole versus placebo for all four categories of AEs according to esomeprazole dosage , treatment indication and duration of treatment . Conclusions : This pooled analysis found no causal association between acid-suppressive therapy with esomeprazole and increased risk of community-acquired RTI , including pneumonia , in patients receiving this agent for gastric acid-related disorders CONTEXT Immune response in elderly individuals has been reported to improve after micronutrient supplementation . However , efficacy trials evaluating infectious diseases as outcomes are scarce and inconclusive . OBJECTIVE To investigate the effect of daily multivitamin-mineral and vitamin E supplementation on incidence and severity of acute respiratory tract infections in elderly individuals . DESIGN A r and omized , double blind , placebo-controlled , 2 x 2 factorial trial . SETTING AND PARTICIPANTS A total of 652 noninstitutionalized individuals aged 60 years or older enrolled from 2 community-based sampling strategies in the Wageningen area of the Netherl and s , conducted from 1998 to 2000 . At baseline , 6 % of participants had suboptimal ascorbic acid and 1.3 % had suboptimal alpha-tocopherol plasma concentration . INTERVENTION Physiological doses of multivitamin-minerals , 200 mg of vitamin E , both , or placebo . MAIN OUTCOME MEASURES Incidence and severity of self-reported acute respiratory tract infections at 15 months , as assessed by a nurse ( telephone contact ) , home visits , and microbiological and serological testing in subsets of patients . RESULTS During a median observation period of 441 days , 443 ( 68 % ) of 652 participants recorded 1024 respiratory tract infection episodes . The incidence rate ratio of acute respiratory tract infection for multivitamin-mineral supplementation was 0.95 ( 95 % confidence interval , 0.75 - 1.15 ; P = .58 ) and for vitamin E supplementation , 1.12 ( 95 % confidence interval , 0.88 - 1.25 ; P = .21 ) . Severity of infections was not influenced by multivitamin-mineral supplementation . For vitamin E vs no vitamin E , severity was worse : median ( interquartile range ) for illness- duration was 19 ( 9 - 37 ) vs 14 ( 6 - 29 ) days , P = .02 ; number of symptoms , 6 ( 3 - 8 ) vs 4 ( 3 - 8 ) , P = .03 ; presence of fever , 36.7 % vs 25.2 % , P = .009 ; and restriction of activity , 52.3 % vs 41.1 % , P = .02 . CONCLUSIONS Neither daily multivitamin-mineral supplementation at physiological dose nor 200 mg of vitamin E showed a favorable effect on incidence and severity of acute respiratory tract infections in well-nourished noninstitutionalized elderly individuals . Instead we observed adverse effects of vitamin E on illness severity Vitamin D has been shown to be an important immune system regulator . Vitamin D insufficiency during winter may cause increased susceptibility to upper respiratory tract infections ( URIs ) . To determine whether vitamin D supplementation during the winter season prevents or decreases URI symptoms , 162 adults were r and omized to receive 50 microg vitamin D3 ( 2000 IU ) daily or matching placebo for 12 weeks . A bi-weekly question naire was used to record the incidence and severity of URI symptoms . There was no difference in the incidence of URIs between the vitamin D and placebo groups ( 48 URIs vs. 50 URIs , respectively , P=0.57 ) . There was no difference in the duration or severity of URI symptoms between the vitamin D and placebo groups [ 5.4+/-4.8 days vs. 5.3+/-3.1 days , respectively , P=0.86 ( 95 % CI for the difference in duration -1.8 to 2.1 ) ] . The mean 25-hydroxyvitamin D level at baseline was similar in both groups ( 64.3+/-25.4 nmol/l in the vitamin D group ; 63.0+/-25.8 nmol/l in the placebo group ; n.s . ) . After 12 weeks , 25-hydroxyvitamin D levels increased significantly to 88.5+/-23.2 nmol/l in the vitamin D group , whereas there was no change in vitamin D levels in the placebo group . There was no benefit of vitamin D3 supplementation in decreasing the incidence or severity of symptomatic URIs during winter . Further studies are needed to determine the role of vitamin D in infection BACKGROUND Hemodialysis ( HD ) patients suffer from several immune defects that make them prone to develop bacterial infections , in particular respiratory tract infections ( RTIs ) . PATIENTS AND METHODS As previous studies have shown that oral immunotherapy with an immunomodulating bacterial extract ( IBE ) is effective against RTIs , we decided to test its efficacy and safety in HD patients during a double-blind placebo-controlled prospect i ve study . 40 HD patients with a documented history of RTIs in the previous year were treated for 24 weeks of the endemic season with one capsule daily of IBE ( n = 21 ) or placebo ( PL , n = 19 ) . Clinical examinations , measurements of Mac-1 and gp150.95 on circulating phagocytes and routine laboratory evaluations were performed at week 0 , 4 , 12 and 24 . Patients were also examined at each dialysis session allowing an accurate recording of any infectious episode , its treatment and of any untoward effect . RESULTS During the last period of the study ( weeks 13 - 24 ) , IBE significantly reduced the number of patients with RTIs and consequently of antibiotic treatment courses as compared to PL ( p = 0.018 ) , whereas no difference was detected between IBE and PL during periods I ( weeks 0 - 4 ) and II ( weeks 5 - 12 ) . There was no difference between IBE and PL for other , non respiratory infections . IBE was associated at several time points with an increased expression on phagocytes of adhesion molecules involved in phagocytosis ( Mac-1 and gp150.95 ) . However , the expression of these molecules was not predictive for the occurrence of RTI . IBE was on the whole as well tolerated as PL , 7 patients presented side effects ( 5 IBE , 2 PL , NS ) which led to drop-out in 4 cases ( 3 IBE , 1 PL ) . No serious side effect was recorded , gastrointestinal upset being the most prevalent type . CONCLUSION The results of this study indicate that immunomodulation with selected bacterial extracts constitutes a promising approach for the prevention of bacterial airway infections in groups at risk , such as HD patients
INTERPRETATION Results indicate that vitamin D has a protective effect against RTI , and dosing once-daily seems most effective .
BACKGROUND Low levels of 25-OH vitamin D are associated with  respiratory tract infection ( RTI ) .
However , results from r and omized controlled trials are inconclusive .
Therefore , we performed a systematic review and meta- analysis to assess the preventive effect of vitamin D supplementation on RTI .