Posttransplantation diabetes mellitus after liver transplant and the impact of family history of diabetes in a Mexican cohort

INTRODUCTION AND AIMS

Posttransplantation diabetes mellitus (PTDM) is a serious long-term complication that has a negative impact on graft and patient survival. The purpose of the present study was to describe the incidence of PTDM in a Mexican cohort and evaluate its association with a previous family history of diabetes (FHD).

METHODS

A retrospective single-center cohort study was conducted on patients undergoing liver transplantation (LT). The primary outcome was time from LT to PTDM. The diagnosis of PTDM was established using the ADA criteria. A mediation analysis that used adjusted Cox regression models and considered pretransplant prediabetes a mediator was performed, to determine the total effect and direct effect of FHD on PTDM.

RESULTS

A total of 152 patients were included, with a median follow-up time of 41 months; 19.2% (n = 29) had pretransplant diabetes. During the follow-up time, 15% of patients developed PTDM (n = 23), with an incidence rate of 4.71 cases/100 person-years. PTDM was significantly higher in patients with FHD, compared with those with no FHD (8.72 cases/100 person-years vs 2.04 cases/100 person-years, respectively; p = 0.001). The adjusted hazard ratio of PTDM for FHD was 4.14 (95% CI 1.60-10.7), p = 0.005) and 3.48 (95% CI 1.35-9.01, p = 0.010), when further controlled for pretransplant prediabetes.

CONCLUSION

The occurrence of PTDM was similar to that reported in most international studies. As with type 2 diabetes, family history plays an important role in the development of PTDM, even after accounting for pretransplant prediabetes. Patients with FHD should undergo a stricter metabolic program.

Associations of Sex, Race, and Apolipoprotein E Alleles With Multiple Domains of Cognition Among Older Adults

Importance

Sex differences are established in associations between apolipoprotein E (APOE) ε4 and cognitive impairment in Alzheimer disease (AD). However, it is unclear whether sex-specific cognitive consequences of APOE are consistent across races and extend to the APOE ε2 allele.

Objective

To investigate whether sex and race modify APOE ε4 and ε2 associations with cognition.

Design, Setting, and Participants

This genetic association study included longitudinal cognitive data from 4 AD and cognitive aging cohorts. Participants were older than 60 years and self-identified as non-Hispanic White or non-Hispanic Black (hereafter, White and Black). Data were previously collected across multiple US locations from 1994 to 2018. Secondary analyses began December 2021 and ended September 2022.

Main Outcomes and Measures

Harmonized composite scores for memory, executive function, and language were generated using psychometric approaches. Linear regression assessed interactions between APOE ε4 or APOE ε2 and sex on baseline cognitive scores, while linear mixed-effect models assessed interactions on cognitive trajectories. The intersectional effect of race was modeled using an APOE × sex × race interaction term, assessing whether APOE × sex interactions differed by race. Models were adjusted for age at baseline and corrected for multiple comparisons.

Results

Of 32 427 participants who met inclusion criteria, there were 19 007 females (59%), 4453 Black individuals (14%), and 27 974 White individuals (86%); the mean (SD) age at baseline was 74 years (7.9). At baseline, 6048 individuals (19%) had AD, 4398 (14%) were APOE ε2 carriers, and 12 538 (38%) were APOE ε4 carriers. Participants missing APOE status were excluded (n = 9266). For APOE ε4, a robust sex interaction was observed on baseline memory (β = -0.071, SE = 0.014; P = 9.6 × 10-7), whereby the APOE ε4 negative effect was stronger in females compared with males and did not significantly differ among races. Contrastingly, despite the large sample size, no APOE ε2 × sex interactions on cognition were observed among all participants. When testing for intersectional effects of sex, APOE ε2, and race, an interaction was revealed on baseline executive function among individuals who were cognitively unimpaired (β = -0.165, SE = 0.066; P = .01), whereby the APOE ε2 protective effect was female-specific among White individuals but male-specific among Black individuals.

Conclusions and Relevance

In this study, while race did not modify sex differences in APOE ε4, the APOE ε2 protective effect could vary by race and sex. Although female sex enhanced ε4-associated risk, there was no comparable sex difference in ε2, suggesting biological pathways underlying ε4-associated risk are distinct from ε2 and likely intersect with age-related changes in sex biology.

Psychosocial evaluation for liver transplantation: A brief guide for gastroenterologists

Liver transplantation is a lifesaving treatment that improves survival and quality of life. The procedure requires adequate transplant candidate selection carried out by a multidisciplinary team. Psychosocial evaluation is a necessary part of recipient selection and its primary aims are to identify problems and psychosocial needs of the patient and his/her family, to improve transplantation outcomes. Different psychosocial conditions are considered risk factors for morbidity and mortality after transplantation. The presence of those factors per se is not an absolute contraindication, thus adequate evaluation promotes equal access to healthcare, improves results, and optimizes resources. The present review provides an overview of and guidelines for the most important psychosocial issues during the pretransplantation phase.

Probability of deceased donor kidney transplantation based on % PRA

Sensitization to HLA antigens creates an obstacle for the accessibility and success of kidney transplantation (KT). Highly sensitized patients have longer waiting times and some may never receive a KT.

AIM

To determine the probability of patients on the deceased donor (DD) waiting list to receive a KT based on the panel reactive antibody percentage (% PRA) in our center.

METHODS

The DD waiting list from our institution was analyzed from 01/05 to 08/12 documenting the clinical variables from donor and potential recipients (ABO blood group), lymphocyte cross-match [CxM (CDC-AHG)] results, highest % PRA determination, and time on the waiting list. The patients were classified into 4 groups based on the % PRA: 0%, 1-19%, 20-79% and 80-100%. The data was analyzed using odds ratio and logistic regression (significant p<0.05).

RESULTS

58 DD (F:M 34:24, ABO group O=35, A=13, B=10) and 179 potential recipients were analyzed (F:M 98:81, ABO group O=127, A=33, B=19, participating 4.2 ± 3.8 times with different donors to receive KT). The mean PRA for the whole group was 22 ± 32%, median [md] 0 (0-98). A total of 100 patients received KT (mean waiting time 2.2 ± 1.7 years, 12 days-7 years) and their mean % PRA was 11.6 ± 24, md 0 (0-94) vs. 31.4 ± 37 md 8.5 (0-98) in those who have not received a KT. An association between the % PRA group and KT (p<0.003) was observed. The probability of receiving KT with a 0% PRA vs. >0% was higher (OR 2.12, 1.17-3.84). There was no difference between the 0% vs. 1-19% group (OR 1); differences were observed between 0% vs. 20-79% (OR 2.5, 1.18-5.3) and 0% vs. 80-100% (OR 5, 1.67-14.9). For every percent increase in the PRA above 20%, the risk of not receiving a KT increased by 5% (1-9, p<0.01).

CONCLUSIONS

The probability of receiving a DD kidney transplant is inversely related to the % PRA although a higher risk for not receiving a KT becomes evident with a PRA >20%.

mTOR-understanding the clinical effects

The target of rapamycin (TOR) is a highly conserved serine/threonine kinase that controls cell growth and metabolism in response to nutrients, growth factors, cellular energy, and stress. The TOR kinase, which was originally discovered in yeast, is also expressed in human cells as mammalian TOR (mTOR). In this review, we focus on how mTOR-inducible signals function in cell protection and cell survival of effector and regulatory T cells as well as its role in endothelial cell biology. We evaluate how signaling is important for vascular endothelial cell growth, survival, and proliferation; and we consider how the function of mTOR in endothelial cells may be clinically important in the rejection process. Understanding the biology of mTOR allows clinicians to use mTOR inhibitors optimally as therapeutics following solid organ transplantation.