Miriam Pavelth Casillas-Ávila

Background: Major depressive disorder (MDD) arises from genetic and environmental factors. We evaluated functional variation in methylenetetrahydrofolate reductase (MTHFR), circulating MTHFR protein, and homocysteine (HCY) in Mexican-Mestizo participants. Methods: We analyzed 1507 individuals across four cohorts: a primary case–control sample (358 DSM-IV-TR MDD cases, 170 psychiatrically screened controls), a community cohort (n = 204), and a general population cohort (n = 775) for allele-frequency context. We genotyped rs1801133 (C677T) and rs13306560 using TaqMan assays. Serum MTHFR and HCY were measured by ELISA in available subsamples (n reported where applicable). Primary analyses tested association of genotypes with MDD under codominant, allelic, and recessive models; false discovery rate (FDR) correction accounted for multiple genetic models. Exploratory multivariable logistic regression adjusted for sex, age, and adverse childhood experiences. Results: The rs13306560 A allele was rare (~2.6%) and showed no association with MDD. Under a recessive model, the rs1801133 TT genotype was more frequent among cases (33.3%) than controls (23.5%) (χ² p = 0.036); this association did not survive FDR correction (q = 0.117) and is reported as hypothesis-generating. In an exploratory adjusted logistic regression (N = 446) using the post hoc recessive coding, TT homozygotes had higher odds of MDD versus CC/CT (OR = 1.98, 95% CI 1.23–3.17, p = 0.005). Serum MTHFR concentrations were higher in cases than controls (median 1834.8 vs. 1241.9 pg/mL; Mann–Whitney U = 343, p = 0.017). Serum MTHFR displayed a borderline positive correlation with HAM-D scores (Spearman r = 0.24, p = 0.050). Conclusions: In this Mexican-Mestizo sample, MTHFR C677T (rs1801133) homozygosity and elevated circulating MTHFR emerged as preliminary, hypothesis-generating candidates for MDD risk. The genetic association did not meet multiple-testing correction (q = 0.117) and requires independent replication; the serum MTHFR case–control difference survived correction (q = 0.034) but warrants confirmation given the small biomarker subsample. A mechanistic study is needed to clarify causality and clinical relevance.

Background: Duchenne muscular dystrophy (DMD) is a genetic disorder characterized by progressive muscle weakness, a decline in quality of life, and premature mortality. This study aims to evaluate the perceived quality of healthcare and the experience of DMD patients and their caregivers in Mexico, comparing governmental and non-profit healthcare institutions using a newly designed assessment instrument. Methods: In a cross-sectional study, data were gathered from 91 participants through an online self-administered questionnaire informed by the Donabedian model and six dimensions of healthcare quality. Results: Analysis revealed two key mediating factors: perceived quality of healthcare and patient experience. The Mann–Whitney U test showed that non-profit organizations were perceived to provide superior quality care in both aspects (p < 0.05), notably regarding healthcare professionals’ preparedness and other domains of quality. However, the patient-centered care domain indicated that the importance of quality domains may vary according to cultural and social contexts. In Mexico, the humanistic approach of healthcare professionals appeared to compensate for shortcomings in timely diagnosis and other quality domains. This emphasizes the necessity for enhanced patient education and healthcare evaluation, and it highlights that patient satisfaction does not always correlate with high-quality healthcare. The developed instrument can further aid in understanding the experiences of DMD patients across different countries and cultures.