The relationship of family history and risk of type 2 diabetes differs by ancestry

Family history of diabetes mellitus and risk of colorectal cancer: A nationwide cohort study

AIMS

Studies have shown the association between personal history of diabetes mellitus (DM type 1/2) and risk of colorectal cancer (CRC). This study aims to find the association between the family history of diabetes and CRC risk.

METHODS

This large nationwide cohort study leveraged data from several Swedish nationwide registers (follow-up: 1964-2018) to compare the risk using standardized incidence ratio (SIR).

RESULTS

11,784,567 individuals (668,348 with DM) were included and followed for up to 54 years (median = 28 years). Those with a personal history of DM had a 1.4-fold increased risk of CRC compared to those without DM (95 % CI: 1.39-1.45). However, the addition of a family history of DM in 1 FDR or ≥ 2 FDRs did not significantly alter the increased risk of early-onset or late-onset CRC.

CONCLUSION

Leveraging one of the world's largest family-disease datasets, our cohort study confirmed that personal history of diabetes is associated with an increased risk of colorectal cancer, but we did not find an association between a family history of diabetes and risk of colorectal cancer.

Parental Transmission of Type 2 Diabetes Risk in Offspring: A Prospective Family-Based Cohort Study in Northern China

Background: While parental type 2 diabetes (T2D) is a known risk factor for offspring T2D, the differential impact of maternal versus paternal transmission remains debated. Methods: This prospective family-based cohort study enrolled 4508 diabetes-free adults from Northern China with a median 7.32-year follow-up. Using Cox proportional hazards models, we examined parent-of-origin effects on T2D incidence, adjusting for lifestyle, adiposity, and metabolic covariates. Results: Parental T2D conferred elevated offspring risk (adjusted HR = 1.82, 95% CI:1.44-2.30), and was predominantly driven by maternal transmission. Maternal T2D was robustly associated with offspring risk (HR = 1.89, 95% CI: 1.47-2.43), whereas paternal T2D showed no significant effect (HR = 1.27, 95% CI: 0.88-1.84). Offspring with only maternal T2D history exhibited the highest risk (HR = 2.55, 95% CI: 1.87-3.50; p = 4.70 × 10-9), persisting after full adjustment, while no significant association was observed for paternal diabetes. Lifestyle modified this association: healthy diet (diet score > 2 vs. ≤2: HR = 1.34 vs. 2.76; pinteraction = 9.10 × 10-4) and regular exercise (regular vs. unregular: HR = 1.13 vs. 2.10; pinteraction = 4.20 × 10-2) attenuated maternal transmission. Conclusions: Maternal T2D confers greater intergenerational risk than paternal T2D, with modifiable lifestyle factors mitigating this association. These findings highlight the importance of integrating maternal diabetes history into clinical risk stratification tools and prioritizing lifestyle interventions in the offspring of affected mothers to mitigate inherited risk.

Family history of type 2 diabetes and the risk of type 2 diabetes among young and middle-aged adults

Background

The prevalence of type 2 diabetes has been growing among younger and middle-aged adults in the United States. A portion of this increase for this age group may be attributable to shared type 2 diabetes risks with family members. How family history of type 2 diabetes history is associated with type 2 diabetes risk among younger and middle-aged adults is not well understood.

Methods

This population-based retrospective cohort study uses administrative, genealogical, and electronic medical records from the Utah Population Database. The study population comprises offspring born between 1970 and 1990 and living in the four urban Utah counties in the United States between 1990 and 2015. The sample comprises 360,907 individuals without a type 2 diabetes diagnosis and 14,817 with a diagnosis. Using multivariate logistic regressions, we estimate the relative risk (RR) of type 2 diabetes associated with the number of affected first- (FDRs), second- (SDRs), and third-degree (first cousin) relatives for the full sample and for Hispanic-specific and sex-specific subsets.

Results

Individuals with 2+ FDRs with type 2 diabetes have a significant risk of type 2 diabetes in relation to those with no affected FDRs (RR = 3.31 [3.16, 3.48]). Individuals with 2+ versus no SDRs with type 2 diabetes have significant but lower risks (RR = 1.32 [1.25, 1.39]). Those with 2+ versus no affected first cousins have a similarly low risk (RR = 1.28 [1.21, 1.35]). Larger RRs are experienced by males (2+ vs. 0 FDRs, RR = 3.55) than females (2+ vs. 0 FDRs, RR = 3.18) (p < 0.05 for the interaction). These familial associations are partly mediated by the individual's own obesity.

Conclusions

The risks of type 2 diabetes are significantly associated with having affected first-, second-, and third-degree relatives, especially for men. One of the forces contributing to the rising patterns of type 2 diabetes among young and middle-aged adults is their connection to affected, often older, kin.

"I Am the Last Priority": Factors Influencing Diabetes Management Among South Asian Caregivers in Peel Region, Ontario

OBJECTIVE

In this study, we aimed to identify sociocultural and systemic factors influencing diabetes management among South Asian (SA) caregivers in Peel Region, Ontario.

METHODS

Twenty-one semistructured interviews were conducted with SA caregivers using a qualitative descriptive design. Data were analyzed using thematic analysis and intersectionality analysis.

RESULTS

Themes identified included 1) prioritizing family caregiving over diabetes self-management; 2) labour market impacts on diabetes self-management; and 3) challenges navigating Canadian health and social service systems. SA caregivers described social, economic, and systemic challenges impacting type 2 diabetes management. Systemic factors influencing diabetes management included discrimination and inequities in labour policies and lack of social and health resources funding. Recommendations by caregivers included whole-family, community-based, culturally tailored approaches to diabetes prevention and management strategies.

CONCLUSIONS

Providing support with system navigation, encouraging family-based approaches, and addressing the social determinants of health could be beneficial for supporting SA families with diabetes management and prevention.

Whole Exome Sequencing Study in a Family with Type 2 Diabetes Mellitus

Background

Type 2 diabetes mellitus (T2DM) is characterized by β cell decline in the pancreas and insulin resistance. This study aimed to investigate the possible pathogenic gene mutation sites of T2DM patients using whole exome sequencing.

Materials and Methods

We recruited a Chinese family with 3-generation history of diabetes. The whole blood genomic DNA of seven members of the family was extracted and sent for whole exome sequencing. Biological information was analyzed with in silico prediction methods, including significance analysis of single nucleotide polymorphism (SNP)/Indel site, and analysis of specific SNP/Indel proteins and their potential mechanisms.

Results

Six out of seven members of the family were diagnosed with diabetes. All DNA samples (23 kb) met quality requirements of library construction. Clean reads of each sample demonstrated high Q20 and Q30 (>80%), indicating good sequencing quality of sequencing data. A total of 130,693 SNPs and 15,928 Indels were found in DNA samples. A total of 22 significant SNPs and Indel mutation sites located on 19 genes were obtained, including ZCCHC3, SYN2, RPL14, SRRD, AMD1, CAMKK2, ZNF787, RNF157, NPIPB15, ALG3, KIAA0040, MAST2, ESRRA, C8orf58, PNLIPRP1, DACH1, MACC1, CAPN9 and DMKN. An rs2305205 mutation of PNLIPRP1 gene and an rs778701848 mutation of CAMKK2 gene may be associated with the pathogenesis of T2DM in this family.

Conclusion

Exons of these diabetic patients demonstrated an rs2305205 mutation in PNLIPRP1 gene and an rs778701848 mutation in CAMKK2 gene. These two mutations might promote T2DM occurrence through reducing sensitivity of peripheral tissue to insulin and reducing insulin secretion.