We assessed the duration and baseline determinants of antibody responses to SARS-CoV-2 spike antigens and the occurrence of reinfections in a prospective cohort of 173 Spanish primary health care worker patients followed initially for 9 months and subsequently up to 12.5 months after COVID-19 symptoms onset. Seropositivity to SARS-CoV-2 spike and receptor-binding domain antigens up to 149–270 days was 92.49% (90.17% IgG, 76.3% IgA, 60.69% IgM). In a subset of 64 health care workers who had not yet been vaccinated by April 2021, seropositivity was 96.88% (95.31% IgG, 82.81% IgA) up to 322–379 days post symptoms onset. Four suspected reinfections were detected by passive case detection, two among seronegative individuals (5 and 7 months after the first episode), and one low antibody responder. Antibody levels significantly correlated with fever, hospitalization, anosmia/hypogeusia, allergies, smoking, and occupation. Stable sustainment of IgG responses raises hope for long-lasting COVID-19 vaccine immunity.

Background: The COVID-19 pandemic has turned the care model of health systems around the world upside down, causing the abrupt cancellation of face-to-face visits and redirection of the model toward telemedicine. Digital transformation boosts information systems—the more robust they are, the easier it is to monitor the health care system in a highly complex state and allow for more agile and reliable analysis. Objective: The purpose of this study was to analyze diagnoses from primary care visits and distinguish between those that had higher and lower variations, relative to the 2019 and 2020 periods (roughly before and during COVID-19), to identify clinical profiles that may have been most impaired from the least-used diagnostic codes for visits during the pandemic. Methods: We used a database from the Primary Care Services Information Technologies Information System of Catalonia. We analyzed the register of visits (n=2,824,185) and their International Classification of Diseases (ICD-10) diagnostic codes (n=3,921,974; mean 1.38 per visit), as approximations of the reasons for consultations, at 3 different grouping levels. The data were represented by a term frequency matrix and analyzed recursively in different partitions aggregated according to date. Results: The increase in non–face-to-face visits (+267%) did not counterbalance the decrease in face-to-face visits (–47%), with an overall reduction in the total number of visits of 1.36%, despite the notable increase in nursing visits (10.54%). The largest increases in 2020 were visits with diagnoses related to COVID-19 (ICD-10 codes Z20-Z29: 2.540%), along with codes related to economic and housing problems (ICD-10 codes Z55-Z65: 44.40%). Visits with most of the other diagnostic codes decreased in 2020 relative to those in 2019. The largest reductions were chronic pathologies such as arterial hypertension (ICD-10 codes I10-I16: –32.73%) or diabetes (ICD-10 codes E08-E13: –21.13%), but also obesity (E65-E68: –48.58%) and bodily injuries (ICD-10 code T14: –33.70%). Visits with mental health–related diagnostic codes decreased, but the decrease was less than the average decrease. There was a decrease in consultations—for children, adolescents, and adults—for respiratory infections (ICD-10 codes J00-J06: –40.96%). The results show large year-on-year variations (in absolute terms, an average of 12%), which is representative of the strong shock to the health system. Conclusions: The disruption in the primary care model in Catalonia has led to an explosive increase in the number of non–face-to-face visits. There has been a reduction in the number of visits for diagnoses related to chronic pathologies, respiratory infections, obesity, and bodily injuries. Instead, visits for diagnoses related to socioeconomic and housing problems have increased, which emphasizes the importance of social determinants of health in the context of this pandemic. Big data analytics with routine care data yield findings that are consistent with those derived from intuition in everyday clinical practice and can help inform decision making by health planners in order to use the next few years to focus on the least-treated diseases during the COVID-19 pandemic.

Repeated COVID-19 mRNA vaccinations increase SARS-CoV-2 IgG4 antibodies, indicating extensive IgG class switching following the first booster dose. This shift in IgG subclasses raises concerns due to the limited ability of IgG4 to mediate Fc-dependent effector functions. To assess the impact of IgG4 induction on protective immunity, we analyzed longitudinal SARS-CoV-2 IgG subclasses, C1q and FcγR responses, and neutralizing activity in a well-characterized cohort of healthcare workers in Spain. Elevated IgG4 levels and higher ratios of non-cytophilic to cytophilic antibodies after booster vaccination were significantly associated with an increased risk of breakthrough infections (IgG4 HR[10-fold increase]=1.8, 95% CI=1.2-2.7; non-cytophilic to cytophilic ratio HR[10-fold increase]=1.5, 95% CI=1.1-1.9). Moreover, an increased non-cytophilic to cytophilic antibody ratio correlated with reduced functionality, including neutralization. These findings suggest a potential association between IgG4 induction by mRNA vaccination and a higher risk of breakthrough infection, warranting further investigation into vaccination strategies to ensure sustained protection.

Data on convalescent plasma (CP) treatment in COVID-19 outpatients are scarce. We aimed to assess whether CP administered during the first week of symptoms reduced the disease progression or risk of hospitalization of outpatients. Two multicenter, double-blind randomized trials (NCT04621123, NCT04589949) were merged with data pooling starting when <20% of recruitment target was achieved. A Bayesian-adaptive individual patient data meta-analysis was implemented. Outpatients aged ≥50 years and symptomatic for ≤7days were included. The intervention consisted of 200–300mL of CP with a predefined minimum level of antibodies. Primary endpoints were a 5-point disease severity scale and a composite of hospitalization or death by 28 days. Amongst the 797 patients included, 390 received CP and 392 placebo; they had a median age of 58 years, 1 comorbidity, 5 days symptoms and 93% had negative IgG antibody-test. Seventy-four patients were hospitalized, 6 required mechanical ventilation and 3 died. The odds ratio (OR) of CP for improved disease severity scale was 0.936 (credible interval (CI) 0.667–1.311); OR for hospitalization or death was 0.919 (CI 0.592–1.416). CP effect on hospital admission or death was largest in patients with ≤5 days of symptoms (OR 0.658, 95%CI 0.394–1.085). CP did not decrease the time to full symptom resolution.Trial registration: Clinicaltrials.gov NCT04621123 and NCT04589949. Registration: NCT04621123 and NCT04589949 on https://www.clinicaltrials.gov

Medical nutrition therapy is an important part of the management of type 1 diabetes mellitus (T1DM). Proper adherence to a healthy diet may have a favorable impact on diabetes management and its diabetic complications. Our aim was to assess differences in food and nutrient intake of type 1 diabetic patients with and without diabetic retinopathy (DR). This was a two-center, cross-sectional study in patients with T1DM, with and without DR. Subjects were recruited from the outpatient clinic of the two participating centers. A validated food frequency questionnaire was administered. A total of 103 T1DM patients with DR and 140 T1DM patient without DR were recruited. Subjects with DR showed a lower intake of total fat (p = 0.036) than that of their non-DR counterparts. DR was associated with increasing age (p = 0.004), hypertension (p < 0.001), and diabetes duration (p < 0.001), however there was a negative association with high educational level (p = 0.018). The multivariate-adjusted analysis showed that the intake of complex carbohydrates was positively related to the presence of DR (p = 0.031). In contrast, the intakes of total fat (p = 0.009), monounsaturated fatty acids (MUFAs) (p = 0.012), oleic acid (p = 0.012), and vitamin E (p = 0.006) were associated with the absence of DR. As conclusions, the intake of total MUFAs, oleic acid, and vitamin E is associated with a lower frequency of DR in patients with T1DM. These results suggest a potential protective effect of these lipid components for DR.

Purpose: This study aims to identify gender disparities in knowledge, attitudes and behaviors related to self-management and control of Type 2 diabetes Mellitus (T2DM) among primary care patients. The research was conducted across multiple Spanish cities. Patients and Methods: The study involved 8 Primary Care Centres located in four distinct regions of Spain: East (Barcelona), Centre (Madrid), North (Pamplona and Zumaia) and South (Vélez-Málaga and Málaga). A total of 111 individuals diagnosed with T2DM, comprising 52 women and 59 men, participated in 12 group discussions at these primary healthcare centers from February to June 2015. Participation was voluntary, and all participants provided informed consent by signing the consent form. A qualitative hermeneutic phenomenological study with a maximum variation sample was done. Participant profiles were defined based on gender, age, place of residence, type of treatment, years living with T2DM and the presence or absence of a cardiovascular event. Thematic analysis was used to analyze the data. Results: Participants were aware that diabetes is a chronic condition, with varied levels of concern regarding the diagnosis. Participants’ locus of control influenced their perception of the disease’s cause, with women attributing it to stress and emotional situations, while men linked it to risky behaviors. Self-management strategies were shaped by beliefs about diabetes, with both genders facing challenges in implementing recommended practices. Gender differences were also evident in caregiving roles, with men receiving more family support for diet adherence, while women prioritized family needs over their self-care. Participants expressed satisfaction with professional-patient interactions but highlighted the need for more accessible information and specialist care, suggesting support groups for women and clear health guidelines for men. Conclusion: Gender differences significantly influence how patients perceive and manage type 2 diabetes, with women experiencing greater concern and care burden compared to men. Effective diabetes management requires tailored support that addresses these gender-specific challenges. Enhancing healthcare services with clear guidelines and support groups can improve self-management outcomes in both men and women.