Delayed Diagnosis of Congenital Myasthenic Syndromes Erroneously Interpreted as Mitochondrial Myopathies.

BACKGROUND: Congenital myasthenic syndromes (CMSs) and primary mitochondrial myopathies (PMMs) can present with ptosis, external ophthalmoplegia, and limb weakness. METHODS: Our method involved the description of three cases of CMS that were initially characterized as probable PMM. RESULTS: All patients were male and presented with ptosis and/or external ophthalmoplegia at birth, with proximal muscle weakness and fatigue on physical exertion. After normal repetitive nerve stimulation (RNS) studies performed on facial muscles, a muscle biopsy (at a median age of 9) was performed to rule out congenital myopathies. In all three cases, the biopsy findings (COX-negative fibers or respiratory chain defects) pointed to PMM. They were referred to our neuromuscular unit in adulthood to establish a genetic diagnosis. However, at this time, fatigability was evident in the physical exams and RNS in the spinal accessory nerve showed a decremental response in all cases. Targeted genetic studies revealed pathogenic variants in the MUSK, DOK7, and RAPSN genes. The median diagnostic delay was 29 years. Treatment resulted in functional improvement in all cases. CONCLUSIONS: Early identification of CMS is essential as medical treatment can provide clear benefits. Its diagnosis can be challenging due to phenotypic overlap with other debilitating disorders. Thus, a high index of suspicion is necessary to guide the diagnostic strategy.

Cognitive Impairment Is a Common Comorbidity in Deceased COVID-19 Patients: A Hospital-Based Retrospective Cohort Study.

We analyzed the frequency of cognitive impairment (CI) in deceased COVID-19 patients at a tertiary hospital in Spain. Among the 477 adult cases who died after admission from March 1 to March 31, 2020, 281 had confirmed COVID-19. CI (21.1% dementia and 8.9% mild cognitive impairment) was a common comorbidity. Subjects with CI were older, tended to live in nursing homes, had shorter time from symptom onset to death, and were rarely admitted to the ICU, receiving palliative care more often. CI is a frequent comorbidity in deceased COVID-19 subjects and is associated with differences in care.

Sugar-sweetened and artificially-sweetened beverages and changes in cognitive function in the SUN project.

Background: Sugar-sweetened beverages (SSB) and artificially-sweetened beverages (ASB) have been inconsistently associated with declines in cognitive function. Because of their low caloric content and replacement of sugar, ASB are often seen as 'healthy' alternatives to SSB. Objective: We longitudinally assessed the association between the consumption of SSB or ASB and cognitive function. Design: A subsample of the 'Seguimiento Universidad de Navarra' (SUN) cohort of university graduates aged over 55 years old was evaluated with the Spanish Telephone Interview for Cognitive Status (STICS-m) at two-time points, separated by 6 years. Consumption of SSB and ASB was appraised using a validated food-frequency questionnaire. Linear regression models were fitted, adjusting for potential confounders, including cardiometabolic variables, with the change in the STICS-m score at year 6 as the dependent variable. Results: A significant association between the consumption of SSB and changes in cognitive function as measured by the STICS-m was observed in the total sample, with a change of -0.43 (95% CI -0.85, -0.02, p = 0.04) in those that consumed >1 beverage/month compared to never/seldom consumers. The association was not significant for the consumption of ASB, but point estimates showed negative values, suggesting declines in cognition. Conclusions: Only the consumption of SSB, but not ASB, was significantly associated with a decline in cognitive function after 6 years. Further longitudinal studies are needed to explore the relationship between these beverages and cognitive function and the potential mechanisms through which they might be harmful.

"A priori" Dietary Patterns and Cognitive Function in the SUN Project.

OBJECTIVES: To study and compare associations of 5 dietary patterns - Mediterranean dietary pattern (MDP), Dietary Approaches to Stop Hypertension (DASH), Mediterranean-DASH Intervention for Neurodegenerative delay (MIND), Alternative Healthy Eating Index (AHEI-2010), and a pro-vegetarian diet (PVD) - with cognitive function. PATIENTS AND METHODS: A subgroup of 806 participants from the "Seguimiento Universidad de Navarra"(SUN) cohort of university graduates, >55 years old, was interviewed with the validated Spanish Telephone Interview for Cognitive Status (STICS-m) at baseline and after 2 and 6 years. For recruitment to the SUN cohort, participants completed a validated food-frequency questionnaire to calculate dietary adherence scores. These scores were used as independent variables in linear regression models (a model for each dietary pattern) to assess their association with the 6-year change in STICS-m as the dependent variable. Linear mixed models were also fitted to compare trajectories of STICS-m scores. All models were adjusted for relevant confounding factors. RESULTS: Adjusted differences showed advantages in the 6-year change in STICS-m score of 0.25 (95% CI 0.04-0.45) for an increase of 1-SD (9 points) in the AHEI-2010 and of 0.27 (95% CI 0.05-0.48) for an increase of 1-SD (1.5 points) in the MIND diet. The MDP, DASH, and PVD scores yielded positive differences in their point estimates for an increase in 1-SD, but results were not statistically significant. The MIND diet appeared to modify changes in cognitive function over time. CONCLUSIONS: Our results showed a beneficial association between the MIND diet and cognitive function and suggested a benefit for the AHEI-2010 pattern. Results for the MDP, DASH, and PVD were inconclusive.