***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: RATIONALE Vitamin D has been shown to be involved in the host immune response toward Mycobacterium tuberculosis . OBJECTIVES To test whether vitamin D supplementation of patients with tuberculosis ( TB ) improved clinical outcome and reduced mortality . METHODS We conducted a r and omized , double-blind , placebo-controlled trial in TB clinics at a demographic surveillance site in Guinea-Bissau . We included 365 adult patients with TB starting antituberculosis treatment ; 281 completed the 12-month follow-up . The intervention was 100,000 IU of cholecalciferol or placebo at inclusion and again 5 and 8 months after the start of treatment . MEASUREMENTS AND MAIN RESULTS The primary outcome was reduction in a clinical severity score ( TBscore ) for all patients with pulmonary TB . The secondary outcome was 12-month mortality . No serious adverse effects were reported ; mild hypercalcemia was rare and present in both arms . Reduction in TBscore and sputum smear conversion rates did not differ among patients treated with vitamin D or placebo .  Overall mortality was 15 % ( 54 of 365 ) at 1 year of follow-up and similar in both arms ( 30 of 187 for vitamin D treated and 24 of 178 for placebo ; relative risk , 1.19 [ 0.58 - 1.95 ] ) . HIV infection was seen in 36 % ( 131 of 359 ) : 21 % ( 76 of 359 ) HIV-1 , 10 % ( 36 of 359 ) HIV-2 , and 5 % ( 19 of 357 ) HIV-1 + 2 . CONCLUSIONS Vitamin D does not improve clinical outcome among patients with TB and the trial showed no overall effect on mortality in patients with TB ; it is possible that the dose used was insufficient . Clinical trial registered with www.controlled-trials.com/is rct n ( IS RCT N35212132 ) BACKGROUND Results from observational studies suggest that micronutrient status is a determinant of the progression of human immunodeficiency virus ( HIV ) disease . METHODS We enrolled 1078 pregnant women infected with HIV in a double-blind , placebo-controlled trial in Dar es Salaam , Tanzania , to examine the effects of daily supplements of vitamin A ( preformed vitamin A and beta carotene ) , multivitamins ( vitamins B , C , and E ) , or both on progression of HIV disease , using survival  models . The median follow-up with respect to survival was 71 months ( interquartile range , 46 to 80 ) . RESULTS Of 271 women who received multivitamins  , 67 had progression to World Health Organization ( WHO ) stage 4 disease or died -- the primary outcome --as compared with 83 of 267 women who received placebo ( 24.7 percent vs. 31.1 percent ; relative risk , 0.71 ; 95 percent confidence interval , 0.51 to 0.98 ; P=0.04 ) . This regimen was also associated with reductions in the relative risk of death related to the acquired immunodeficiency syndrome ( 0.73 ; 95 percent confidence interval , 0.51 to 1.04 ; P=0.09 ) , progression to WHO stage 4 ( 0.50 ; 95 percent confidence interval , 0.28 to 0.90 ; P=0.02 ) , or progression to stage 3 or higher ( 0.72 ; 95 percent confidence interval , 0.58 to 0.90 ; P=0.003 ) . Multivitamins also result ed in significantly higher CD4 + and CD8 + cell counts and significantly lower viral loads . The effects of receiving vitamin A alone were smaller and for the most part not significantly different from those produced by placebo . Adding vitamin A to the multivitamin regimen reduced the benefit with regard to some of the end points examined . CONCLUSIONS Multivitamin supplements delay the progression of HIV disease and provide an effective , low-cost means of delaying the initiation of antiretroviral therapy in HIV-infected women OBJECTIVES We have previously investigated the role of either : aspirin and micronutrients or aspirin , micronutrients and chloroquine ( CQ ) in the management of asymptomatic HIV infected individuals . In this paper , we report the use of these combinations in the management of patients with AIDS , defined as CD4 count < 200 cells Background : Iron deficiency is common among female injection drug users , but it is unclear whether iron supplementation can reduce anemia and improve iron status without increasing plasma hepatitis C virus ( HCV ) or HIV RNA levels . Methods : We conducted a phase 3 , double-blind , r and omized , controlled clinical trial of daily micronutrients with 18 mg of iron ( iron group ) versus micronutrients without iron ( control group ) for 12 months among hepatitis C-positive female injection drug users in Baltimore , Maryl and . The main outcome measures were hemoglobin , markers of iron status , plasma HCV RNA , plasma HIV RNA , and liver enzymes at 6 and 12 months of follow-up . Results : Four hundred fifty-eight women ( 320 HIV-negative and 138 HIV-positive ) enrolled in the trial . There were no significant differences in the proportion of women with anemia , ferritin < 30 ng/mL , log10 plasma HCV RNA , or log10 plasma HIV RNA between treatment groups at enrollment . The proportion with anemia in the iron and control groups , respectively , was 20.7 % versus 31.3 % ( P = 0.026 ) at 6 months and 26.2 % versus 30.4 % ( P = 0.5 ) at 12 months ; with ferritin < 30 ng/mL , the proportion was 29.2 % versus 55.5 % ( P < 0.0001 ) at 6 months and 26.2 % versus 46.9 % ( P = 0.0018 ) at 12 months . In the iron and control groups , respectively , mean log10 plasma HCV RNA ( IU/mL ) was 5.2 versus 5.2 ( P = 0.86 ) at 6 months and 5.4 versus 5.3 ( P = 0.6 ) at 12 months . Among HIV-positive subjects , mean log10 plasma RNA ( copies/mL ) in the iron and placebo groups , respectively , was 3.8 versus 3.7 ( P = 0.75 ) at 6 months and 3.7 versus 4.1 ( P = 0.19 ) at 12 months . There were no significant differences in liver enzyme levels between the treatment groups at enrollment , 6 months , and 12 months . Conclusions : A daily micronutrient supplement with iron can reduce anemia and improve iron status in female injection drug users without increasing plasma HCV or HIV RNA levels or altering liver enzymes BACKGROUND Evidence has accumulated from observational studies that people eating more fruits and vegetables , which are rich in beta-carotene ( a violet to yellow plant pigment that acts as an antioxidant and can be converted to vitamin A by enzymes in the intestinal wall and liver ) and retinol ( an alcohol chemical form of vitamin A ) , and people having higher serum beta-carotene concentrations had lower rates of lung cancer . The Beta-Carotene and Retinol Efficacy Trial ( CARET ) tested the combination of 30 mg beta-carotene and 25,000 IU retinyl palmitate ( vitamin A ) taken daily against placebo in 18314 men and women at high risk of developing lung cancer . The CARET intervention was stopped 21 months early because of clear evidence of no benefit and substantial evidence of possible harm ; there were 28 % more lung cancers and 17 % more deaths in the active intervention group ( active = the daily combination of 30 mg beta-carotene and 25,000 IU retinyl palmitate ) . Promptly after the January 18 , 1996 , announcement that the CARET active intervention had been stopped , we published preliminary findings from CARET regarding cancer , heart disease , and total mortality . PURPOSE We present for the first time results based on the pre-specified analytic method , details about risk factors for lung cancer , and analyses of subgroups and of factors that possibly influence response to the intervention . METHODS CARET was a r and omized , double-blinded , placebo-controlled chemoprevention trial , initiated with a pilot phase and then exp and ed 10-fold at six study centers . Cigarette smoking history and status and alcohol intake were assessed through participant self-report . Serum was collected from the participants at base line and periodically after r and omization and was analyzed for beta-carotene concentration . An Endpoints Review Committee evaluated endpoint reports , including pathologic review of tissue specimens . The primary analysis is a stratified logrank test for intervention arm differences in lung cancer incidence , with weighting linearly to hypothesized full effect at 24 months after r and omization . Relative risks ( RRs ) were estimated by use of Cox regression models ; tests were performed for quantitative and qualitative interactions between the intervention and smoking status or alcohol intake . O'Brien-Fleming boundaries were used for stopping criteria at interim analyses . Statistical significance was set at the .05 alpha value , and all P values were derived from two-sided statistical tests . RESULTS According to CARET 's pre-specified analysis , there was an RR of 1.36 ( 95 % confidence interval [ CI ] = 1.07 - 1.73 ; P = .01 ) for weighted lung cancer incidence for the active intervention group compared with the placebo group , and RR = 1.59 ( 95 % CI = 1.13 - 2.23 ; P = .01 ) for weighted lung cancer mortality . All subgroups , except former smokers , had a point estimate of RR of 1.10 or greater for lung cancer . There are suggestions of associations of the excess lung cancer incidence with the highest quartile of alcohol intake ( RR = 1.99 ; 95 % CI = 1.28 - 3.09 ; test for heterogeneity of RR among quartiles of alcohol intake has P = .01 , unadjusted for multiple comparisons ) and with large-cell histology ( RR = 1.89 ; 95 % CI = 1.09 - 3.26 ; test for heterogeneity among histologic categories has P = .35 ) , but not with base-line serum beta-carotene concentrations . CONCLUSIONS CARET participants receiving the combination of beta-carotene and vitamin A had no chemopreventive benefit and had excess lung cancer incidence and mortality . The results are highly consistent with those found for beta-carotene in the Alpha-Tocopherol Beta-Carotene Cancer Prevention Study in 29133 male smokers in Finl and BACKGROUND In observational studies , the zinc status of HIV-infected persons has been associated with both positive and adverse clinical outcomes . Such endpoints may affect the risk of adverse birth outcomes among HIV-infected women . OBJECTIVE We examined the effects of zinc supplements on birth outcomes , hematologic indicators , and counts of T lymphocyte subsets among 400 HIV-infected pregnant women . DESIGN Eligible women between 12 and 27 wk of gestation were r and omly assigned to daily oral supplementation with either 25 mg Zn or placebo between recruitment and 6 wk after delivery . All women received iron , folic acid , and multivitamin supplements irrespective of the experimental assignment . RESULTS We observed no significant differences in birth weight , duration of gestation , or fetal and neonatal mortality between women in the zinc and placebo groups . Hemoglobin concentrations increased between baseline and 6 wk postpartum in both groups . However , the rise in hemoglobin over this period was significantly lower ( P = 0.03 ) in the zinc group ( x + /- SD : 11.5 + /- 17.9 g/L ) than in the placebo group ( 15.2 + /- 18.6 g/L ) . Similarly , the changes in red blood cell count and in packed cell volume over the same period were significantly lower in the zinc group ( P < 0.01 and P = 0.01 , respectively ) . Zinc had no effect on CD4(+ ) , CD8(+ ) , or CD3(+ ) cell counts during the follow-up period . CONCLUSION Because of the lack of beneficial effects of zinc on adverse pregnancy outcomes and the likelihood of negative effects on hemoglobin concentrations , no compelling evidence exists to support the addition of zinc to prenatal supplements intended for pregnant HIV-infected women Iron deficiency is one of the main causes of anemia during pregnancy , although other micronutrient deficiencies may play a role . We examined the effects of daily antenatal and postnatal supplementation with four combinations of micronutrients on  maternal hematologic indicators  in a double-masked r and omized controlled community trial . Communities , called sectors , were r and omly assigned to supplementation with folic acid ( 400 microg ) , folic acid plus iron ( 60 mg ) , folic acid plus iron and zinc ( 30 mg ) and folic acid plus iron , zinc and 11 other micronutrients , each at the approximate recommended daily allowance for pre 
    Output:
    
None of the six trials of vitamin A or beta-carotene supplementation in adults demonstrated any significant reduction in HIV disease progression .
No significant adverse effects of vitamin A in adults or children have been reported .
Zinc supplements reduced diarrhoeal morbidity and had no adverse effects on disease progression in a single safety trial in South African children .
No significant clinical benefits were found from zinc supplementation of pregnant Tanzanian women or Peruvian adults with persistent diarrhoea .
Vitamin A supplementation is beneficial and safe in HIV-infected children , but further evidence is needed to establish if supplementation confers similar benefits in HIV-infected adults .
Zinc is safe in HIV-infected adults and children .
It may have similar benefits in HIV-infected children and adults , and uninfected children with diarrhoea , as it does in HIV-uninfected children .