***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 
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    Input: Purpose The objective of this study was to identify patient characteristics positively and independently associated with 131I-iodide treatment failure in a large cohort of patients with Graves hyperthyroidism treated with either a calculated “ st and ard ” activity of 3.7 MBq/mL ( 0.1 mCi ) or 7.4 MBq/mL ( 0.2 mCi ) of thyroid volume . Methods Data on 385 consecutive patients were prospect ively collected . Clinical treatment outcome up to 1 year in relation to thyroid volume , 5- and 24-hour 131I uptake , 5/24-hour 131I uptake ratio , and the administered activity of radioiodine were analyzed . Results Overall treatment results were hypothyroidism in 46 % , euthyroidism in 29 % , and recurrent hyperthyroidism in 26 % of patients . Thyroid volume ( P = 0.000 ) , 5/24-hour uptake ratio ( P = 0.000 ) , and 5- and 24-hour uptake alone ( respectively , P = 0.000 and P = 0.002 ) were significantly associated with therapy outcome . Patients with a combination of a thyroid volume greater than 50 mL and a 5/24-hour uptake ratio 0.8 or greater showed treatment failure in 70 % and 42 % ( respectively , 3.7 MBq/mL , n = 20 ; and 7.4 MBq/mL , n = 41 ) . Thyroid volume and 5/24-hour uptake ratio were positively and independently associated with recurrent hyperthyroidism ( respectively , odds ratio [ OR ] , 5.3 ; 95 % confidence interval [ CI ] , 2.39–11.76 ; and OR , 2.97 ; 95 % CI , 1.59–5.59 ) . Higher activities of 7.4 MBq/mL 131I were associated with a lower risk of treatment failure ( OR , 0.34 ; 95 % CI , 0.18–0.62 ) . Conclusions Large thyroid volumes and high 5/24-hour uptake ratios are positively and independently associated with recurrent hyperthyroidism following 131I therapy in Graves hyperthyroidism . Higher success rates can be achieved when account is taken of these poor prognostic factors . In consequence , these patients should be treated with activities greater than 7.4 The optimal method for determining iodine-131 treatment doses for Graves ' hyperthyroidism is unknown , and techniques have varied from a fixed dose to more elaborate calculations based upon gl and size , iodine uptake , and iodine turnover . Patients with Graves ' hyperthyroidism ( n = 88 ) who had not been previously treated with radioactive iodine  were r and omized to one of four dose calculation methods : low-fixed , 235 MBq ; high-fixed , 350 MBq ; low-adjusted , 2.96 MBq ( 80 micro Ci)/g thyroid adjusted for 24 h radioiodine uptake ; and high-adjusted , 4.44 MBq ( 120 micro Ci)/g thyroid adjusted for 24 h radioiodine uptake . Subjects were followed for mean of 63 months ( range , 10 - 94 months ) for the following clinical outcomes : euthyroid without medication , hyperthyroid requiring further radioiodine , and hypothyroid requiring life-long L-T(4 ) . Mean treatment doses were similar in the different outcome groups . We could not demonstrate any advantage to using an adjusted dose method . Survival analysis did not demonstrate any difference in the time to outcome between the fixed and adjusted dose methods . The use of a fixed dose method simplifies the approach to treatment with potential cost savings In order to avoid selective biases and to minimize r and om errors , inference about the effects of treatment on serious endpoints needs to be based not on one , or a few , of the available trial results , but on a systematic overview of the totality of the evidence from all the relevant unconfounded r and omized trials . But , only where coverage of all , or nearly all , r and omized patients in all relevant trials ( or a reasonably unbiased sample of such trials ) can be assured , is a systematic overview of trials reasonably trustworthy , for then any selective biases are likely to be small in comparison with any moderate effects of treatment . Checks for the existence of such biases can best be conducted if reasonably detailed data are available from each trial . Future trials should take into account the results of any relevant overviews in their design , and should plan to obtain sufficient numbers of events to contribute substantially to such overviews . In many cases , this implies the need for r and omized trials that are much larger than is currently st and ard Effectiveness of radioiodine for Graves ' hyperthyroidism depends also on its intrathyroidal persistence . The latter is enhanced by lithium by blocking iodine release from the thyroid . One hundred ten patients with Graves ' hyperthyroidism were r and omly assigned to treatment with radioiodine or radioiodine plus lithium , stratified according to goiter size ( < or = 40 or > 40 mL ) and evaluated for changes in thyroid function and goiter size , at monthly intervals , for 12 months . Cure of hyperthyroidism occurred in 33 of 46 patients ( 72 % ) treated with radioiodine and in 45 of 54 patients ( 83 % ) treated with radioiodine plus lithium . The probability of curing hyperthyroidism was higher and its control prompter ( P = 0.02 ) in the radioiodine-plus-lithium group . Patients with < or = 40-mL goiters had similar persistence of hyperthyroidism ( 13 % ) , but lithium-treated patients had hyperthyroidism controlled earlier ( P = 0.04 ) . Among patients with > 40-mL goiters , hyperthyroidism was cured in 6 of 15 patients ( 40 % ) treated with radioiodine alone and in 12 of 16 patients ( 75 % ) treated with radioiodine plus lithium ( P = 0.07 ) , and cure occurred earlier in the latter ( P = 0.05 ) . Goiters shrank in both groups ( P < 0.0001 ) , more effectively and promptly ( P < 0.0005 ) in the radioiodine-plus-lithium group . Serum free T4 and T3 levels increased shortly after therapy only in the radioiodine group ( P < 0.01 ) . Lithium carbonate enhances the effectiveness of radioiodine therapy , in terms of prompter control of hyperthyroidism , in patients with small or large goiters . In the latter group , lithium also increases the rate of permanent control of hyperthyroidism AIM Evaluation of intrathyroidal kinetics of radioiodine with and without lithium as adjunct with respect to the increase in radiation dose delivered to the thyroid . PATIENTS , METHODS 267 patients in three groups were included in the study . Group I with 227 patients served as control group , Group II with 21 patients and Group III with 19 patients were distinguished by an intrathyroidal half-life of radioiodine below 3.5 days in the diagnostic test . Patients in Group III received 885 mg lithium carbonate a day for 2 weeks as adjunct to radioiodine therapy . Both diagnostic and therapeutic radioiodine kinetics were followed up by at least 10 uptake measurements within a minimum of 48 h. Kinetics of radioiodine were defined mathematically as balance of the thyroidal iodine intake and excretion by a two-compartment model . RESULTS Under therapy the maximum uptake of radioiodine was reduced by nearly 10 % in all groups , in Group I , the effective half-life as well as the product of maximum uptake x effective half-life as an equivalent of radiation dose independent of thyroid volume was lowered in the same magnitude . In Group II , the energy-dose equivalent remained constant under therapy . With adjunct lithium in Group III , the effective half-life was prolonged significantly by factor 1.61 + /- 0.49 and the volume-independent energy-dose equivalent by factor 1.39 + /- 0.37 . No severe side effects of lithium were observed . CONCLUSION Using lithium as adjunct to radioiodine therapy increases the radiation dose delivered to the thyroid by 39 % on average and nearly 30 % of radioiodine activity can be saved in these patients . Lithium is recommended in patients with very short effective half-life in the diagnostic test in order to reduce the activity required and whole-body radiation dose 16 patients with diffuse thyroid hyperplasia were given lithium carbonate ( 400 mg daily ) for 1 week before and 1 week after a st and ardised 5 mCi therapy dose of 131I . A comparable control group of 16 patients were treated with 5 mCi of 131I without lithium therapy . The % retention of the therapy dose was measured in all patients at 7 days ( 168-hour 131I uptake ) . In the lithium-treated group the 24-hour 131I uptake showed no significant change after the first week of lithium therapy . The mean 48-hour protein-bound 131I , however , fell considerably from 1 - 21 to 0.55%/dose/1 . The mean 24 - 168 hour % thyroidal 131I uptake drop was significantly less in the lithium group . These results show that low-dosage lithium therapy increases the retention of a st and ard-therapy dose of 131I .  Lithium promises to be a useful adjunct to 131I therapy in patients with a rapid thyroidal iodine turnover and particularly in young patients where the total body-radiation dose must be kept to a minimum Serum thyroid hormone concentrations increase after radioiodine ( RAI ) therapy for Graves ' disease . This phenomenon has been ascribed to either antithyroid drug withdrawal before RAI therapy or release of preformed thyroid hormones into the bloodstream from the RAI-damaged thyroid . Lithium blocks the release of iodine and thyroid hormones from the thyroid , thus enhancing the effectiveness of RAI therapy . Changes in serum-free thyroxine ( FT4 ) and triiodothyronine ( FT3 ) levels after methimazole ( MMI ) discontinuation and RAI therapy were evaluated in a prospect i ve , r and omized , control study of 36 patients with Graves ' disease . After a 3- to 4-month course of MMI , patients were assigned to one of three groups : G1 ( RAI alone ) ; G2 ( RAI plus lithium for 6 d starting on the day of RAI therapy ) ; or G3 ( RAI plus lithium for 19 d starting on the day of MMI withdrawal ) . G1-G2 patients had an increase in serum FT4 and FT3 levels from 13.5 + /- 6.5 to 19.8 + /- 9.2 pmol/liter and 5.0 + /- 2.0 to 8.0 + /- 4.8 pmol/liter , respectively ( P < 0.0001 ) , 2 - 5 d after MMI withdrawal , but G3 patients showed no changes . In the 30 d after RAI therapy , mean serum FT4 values increased in G1 patients ( P = 0.02 ) , peaking at 3 - 7 d ( P < 0.05 ) but not in G2 and G3 patients . Serum FT3 levels decreased in G1 , G2 , and G3 ( P = 0.03 , P = 0.001 , P = 0.02 , respectively ) . Hyperthyroidism was cured in 8 of 12 G1 patients , 11 of 12 G2 patients , and 11 of 12 G3 patients ( P = 0.31 ) . Control of hyperthyroidism was prompter in G2 ( P = 0.08 ) and G3 ( P < 0.05 ) than in G1 patients . Patients in the three groups received a similar dose of RAI , but the committed radiation to the thyroid was higher in G3 ( 563 + /- 174 Gray ) and G2 ( 588 + /- 347 Gray ) than in G1 ( 429 + /- 204 Gray ) ( P < 0.03 ) . In conclusion , the results of the present study demonstrate that : 1 ) MMI withdrawal is associated with a slight rise in serum thyroid hormone levels ; 2 ) a further increase occurs after RAI therapy ; 3 ) changes in serum thyroid hormone concentrations are prevented by lithium ; and 4 ) the increased effectiveness of RAI therapy  in lithium-treated patients is related to the increased RAI retention in the thyroid gl and . Accordingly , a short course of lithium therapy can be considered a useful adjunct to RAI therapy to obtain a prompter control of thyrotoxicosis and avoid its transient exacerbation because of MMI withdrawal and RAI administration INTRODUCTION The effects of selected drugs ( see below ) on the efficacy of ( (131)I ) radioiodine therapy were examined . MATERIAL AND METHODS The study involved 200 hyperthyroid patients , treated with radioactive iodine .  They were divided into five groups ( 40 persons in each ) . In Group I - patients were administered (131)I and thiamazole ; in Group II they were given - (131)I and lithium carbonate ; in Group III they were given - (131)I only ( the assumed absorbed dose - 150 - 200 Gy , the same as in Groups I and II , for which Group III was a control group ) ; in Group IV they 
    Output:
    
Adjunctive lithium reduced time to cure and blunted thyroid hormone excursions after RAI .
Lithium-related  side effects were infrequent and usually mild .
The observational trials demonstrated significant improvement in the cure rate of hyperthyroidism when lithium is added to RAI .