4.1. Discussion of Cognitive Performance Results
cognitive impairment, non-amnestic
PATHOLOGY
The results of this study show an improvement in “orientation”, assessed both in the MOCA test and in the MMSE test (temporal orientation), after daily consumption of 50 g of Málaga muscatel raisins. In addition, in the “visuospatial/executive” and “language” categories, also assessed with the MOCA test, a higher score was observed in the IG after 6 months. In the final score of the MOCA test, we also observed a significant improvement in the IG. With the Rey Verbal Auditory Learning test, we observed an improvement in the “immediate recall” and in the “retention memory” of a list of 15 words, in the IG subjects after a non-amnestic interference task. “Immediate recall” is understood as the number of words recalled on the first attempt after the researcher has read 15 words. The “retention memory” is the number of words correctly remembered 30 min after a non-amnestic interference task (maximum 15 words).However, no relevant differences were found in the other items evaluated with the Mini-Mental State Examination test (“spatial orientation”, “memory and fixation”, “attention and calculation”, “memory”, “naming and repetition” and “comprehension”, reading, writing and drawing”) nor with the MOCA test (“identification”, “memory”, “attention”, “concentration”, “similarities” and “delayed recall”). No differences were observed in verbal fluency either, used in the estimation of the sample size.The effect of raisins on cognitive performance has not been previously studied. However, an abundance of literature shows that polyphenolic compounds, mainly the families of flavonols, flavanols, and stilbenes, could have a beneficial effect at a cognitive level. These families of compounds are well represented in raisins, as shown in Following a review on this topic, attention was found to improve with a flavanol 900 mg/day supplement for 2 months [For all these reasons, we can say that the accuracy of the tool used to assess cognition in this type of study is key to making an adequate evaluation. There are several studies in which the MMSE test is used, and like us, they do not observe changes in the final score after the intervention, and yet they do with other tests [Similar results to those observed in our work have been described by Lopresti et al. in older adults with mild cognitive impairment. The IG obtained significant improvements in “visuospatial learning”, as well as in other cognitive functions such as “speed of information processing” after a daily supplement of 150 mg of grape and blueberry polyphenol extract twice daily for 6 months [Witte et al. demonstrated higher scores in delayed recall and word recognition after daily supplementation with 200 mg of resveratrol and 320 mg of quercetin for 6 months [With the Rey Auditory Verbal Learning Test, both our study and Witte et al. observed improvement after the intervention in healthy patients. However, when analyzing the influence of a daily supplement of 200 mg of resveratrol and 350 mg of quercetin for 26 weeks (very similar to the product used by Witte et al., who used 200 mg of resveratrol and 320 mg of quercetin for 6 months) on patients with cognitive pathology, no changes are observed [In general, foods of plant origin contain different polyphenolic compounds with different concentrations. In addition, the total content of polyphenols in foods is influenced by edaphoclimatic factors and culinary preparation. Other foods rich in polyphenols that have been shown to improve cognitive aspects are, among others, cocoa [This study, like other articles mentioned, can also affirm that flavonoids, present in raisins, may be related to better cognitive performance.