You will be presented with a collection of medical randomized controlled trial (RCT) reports addressing a shared clinical question -- for instance, the efficacy of a medical intervention on a disease or condition. Given the titles and abstracts of these reports, your task is to generate the conclusion of the systematic review article synthesizing the key findings. Your conclusion should be a few sentences long. In your response, include only the conclusion and no other text. The RCT reports are below.



Title 1:
Thiamine therapy in Alzheimer's disease
Abstract 1:
Fursultiamine ( TTFD ) , a derivative of thiamine , at an oral dose of 100 mg/day had a mild beneficial effect in patients with Alzheimer 's disease in a 12-week open trial . The improvement could be observed not only in their emotional or other mental symptoms but also in intellectual function . Only mildly impaired subjects showed cognitive improvement . Alzheimer patients '  blood levels of thiamine  before the trial were within the normal range . No adverse reactions were observed and all patients tolerated the trial well . TTFD could afford an alternate treatment to large doses of thiamine hydrochloride in Alzheimer patients . However , further investigations of the therapeutic implication s of thiamine and its possible etiologic clues to Alzheimer 's disease are necessary


Title 2:
A trial of thiamine in Alzheimer's disease.
Abstract 2:
Because a previous short-term study demonstrated a statistically significant , but not clinical ly important , improvement in cognitive test scores during thiamine treatment in patients with dementia of the Alzheimer 's type , a 12-month , double-blind , parallel-group study was conducted to examine whether long-term administration of thiamine at 3 g/d might slow the progression of dementia of the Alzheimer 's type . Fifteen subjects were enrolled and 10 completed the 1-year study . Data are available for two additional subjects through the first 9 months of study . No significant differences were found between the placebo and thiamine groups at any point during the study . In both groups , overall means for the Mini-Mental State Examination , verbal learning , and naming scores decreased significantly over the 12-month study period . These results do not support the hypothesis that long-term administration of thiamine at 3 g/d might slow the progression of dementia of the Alzheimer 's type


Title 3:
Preliminary Findings of High-Dose Thiamine in Dementia of Alzheimer's Type
Abstract 3:
Thiamine is important not only in the metabolism of acetylcholine but also in its release from the presynaptic neuron . Pathologic , clinical , and biochemical data suggest that thiamine deficiency is detrimental to the cholinergic system and that thiamine-dependent enzymes may be altered in Alzheimer 's disease . Two previous studies reported contradictory results in patients with dementia of Alzheimer 's type treated with 3 g/day of thiamine . In the present study , we examined the effects of 3 to 8 g/day thiamine administered orally . Our results suggest that thiamine at these pharmacologic dosages may have a mild beneficial effect in dementia of Alzheimer 's type . The mechanism of the observed effect is unknown , but the findings warrant further investigation , not only for their therapeutic implication s but for their possible etiologic clues . In addition , the results suggest long-term carry-over effects that should be considered in the design of future studies


Title 4:
Thiamine and Alzheimer's disease. A pilot study.
Abstract 4:
As a test of the significance of previously described biochemical abnormalities in thiamine-dependent enzymes in brains and other tissues in patients with Alzheimer 's disease , a double-blind , placebo-controlled , crossover , outpatient pilot study compared the effects of 3 g/d of oral thiamine hydrochloride for three months with those of a niacinamide placebo .  Eleven moderately impaired patients with " probable Alzheimer 's disease " by the National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer 's Disease and Related Disorders Association criteria completed the study . All patients were well nourished and had no stigmata of dietary thiamine deficiency . Their initial mean + /- SEM Mini-Mental State Examination score was 14.2 + /- 1.4 , and the mean age was 72 years .  Global cognitive rating by the Mini-Mental State Examination was higher during three months with 3 g/d of oral thiamine hydrochloride than with niacinamide placebo .  Behavioral ratings , however , did not differ significantly , nor did clinical state when it was judged subjectively
The data were compatible with thiamine producing harm , no change or improvement .
There was no statistically significant difference in the test of Verbal Fluency and the Boston Naming Test .
REVIEW ER 'S CONCLUSIONS This review finds no evidence that thiamine is a useful treatment for the symptoms of Alzheimer 's disease .
Thiamine can not be recommended for patients with Alzheimer 's disease