Stopping insulin injections following genetic testing in diabetes: impact on identity

Quality of Life and Treatment Satisfaction in Participants with Maturity-Onset Diabetes of the Young: A Comparison to Other Major Forms of Diabetes

AIMS

We investigated the quality of life (QoL), treatment satisfaction and perception of genetic results in participants with Maturity-Onset Diabetes of the Young (MODY) and compared the results with those of subjects with type 1 (T1D) or type 2 (T2D) diabetes.

METHODS

A total of 162 adults with GCK-MODY, 62 with HNF1A-MODY and 29 with HNF4A-MODY answered the questionnaire Audit of Diabetes Dependent Quality of Life, the Diabetes Treatment Satisfaction Questionnaire and non-validated instrument examining the respondent's perception of the genetic results. Data from GCK-MODY patients were compared with 84 participants with T2D and HNF-MODY subjects were compared with 81 participants having T1D.

RESULTS

Higher age (p=0.004), higher haemoglobin A1c (p=0.026) and medication (p=0.019) were associated with lower general QoL in GCK-MODY patients. In HNF-MODY patients, lower general QoL was associated with a longer time since diagnosis (p=0.005), worse haemoglobin bA1c (p=0.006) and insulin treatment (p=0.019). Similar numbers of participants with GCK- and HNF-MODY considered the genetic diagnosis of MODY to be positive, negative and without significance. The patient with GCK-MODY did not differ from those with T2D in terms of their QoL, but they were less satisfied with their treatment (p<0.001). QoL was better in patients with HNF-MODY compared with patients with T1D (p=0.006), and they did not differ in terms of treatment satisfaction.

CONCLUSIONS

QoL was affected in both GCK-MODY and HNF-MODY subjects. Apprehension of genetic diagnosis was not single-valued in MODY respondents.

Patient perspectives on the diagnostic journey to a monogenic diabetes diagnosis: Barriers and facilitators

Most monogenic diabetes is misdiagnosed as either type 1 or type 2 diabetes (T1D/T2D). Few studies have examined the diagnostic challenges from the patients' perspective. This qualitative study aimed to investigate patients' journeys to obtaining a diagnosis of maturity-onset diabetes of the young (MODY) by elucidating the range of factors that can act as barriers and facilitators throughout this process. We recruited participants from the Personalized Diabetes Medicine Program (PDMP) at University of Maryland and used respondent-driven sampling to recruit additional patients. We conducted qualitative phone interviews between October 2016 and June 2017 with nine patients with diagnoses of monogenic diabetes (one HNF4A-MODY, seven GCK-MODY, and one HNF1A-MODY) and one parent of a patient with INS-MODY. Interview data were audio recorded, transcribed, and analyzed both inductively and deductively using thematic content analysis. All patients were female, with a mean age of 35 (range: 7-67 years). The amount of time these patients were misdiagnosed ranged from a few months to 41 years. We identified barriers and facilitators in three broad themes: (a) patient-related (nature of MODY symptoms, perceived test utility, individual personality); (b) provider-related (provider awareness and knowledge, provider communication); and (c) healthcare system-related (cost of testing, access to knowledgeable providers, patient education, and support resources). The diverse range of barriers and facilitators reiterates the complexity of the MODY diagnostic process. Limited awareness and knowledge of MODY from healthcare professionals and patients themselves account for most diagnostic delays described in this study. Efforts to promote awareness of MODY and expand access to screening and testing may result in quicker diagnosis and ensure the downstream benefits of proper treatment.

Absence of Islet Autoantibodies and Modestly Raised Glucose Values at Diabetes Diagnosis Should Lead to Testing for MODY: Lessons From a 5-Year Pediatric Swedish National Cohort Study

OBJECTIVE

Identifying maturity-onset diabetes of the young (MODY) in pediatric populations close to diabetes diagnosis is difficult. Misdiagnosis and unnecessary insulin treatment are common. We aimed to identify the discriminatory clinical features at diabetes diagnosis of patients with glucokinase (GCK), hepatocyte nuclear factor-1A (HNF1A), and HNF4A MODY in the pediatric population.

RESEARCH DESIGN AND METHODS

Swedish patients (n = 3,933) aged 1-18 years, diagnosed with diabetes May 2005 to December 2010, were recruited from the national consecutive prospective cohort Better Diabetes Diagnosis. Clinical data, islet autoantibodies (GAD insulinoma antigen-2, zinc transporter 8, and insulin autoantibodies), HLA type, and C-peptide were collected at diagnosis. MODY was identified by sequencing GCK, HNF1A, and HNF4A, through either routine clinical or research testing.

RESULTS

The minimal prevalence of MODY was 1.2%. Discriminatory factors for MODY at diagnosis included four islet autoantibody negativity (100% vs. 11% not-known MODY; P = 2 × 10^-44), HbA_1c (7.0% vs. 10.7% [53 vs. 93 mmol/mol]; P = 1 × 10^-20), plasma glucose (11.7 vs. 26.7 mmol/L; P = 3 × 10^-19), parental diabetes (63% vs. 12%; P = 1 × 10^-15), and diabetic ketoacidosis (0% vs. 15%; P = 0.001). Testing 303 autoantibody-negative patients identified 46 patients with MODY (detection rate 15%). Limiting testing to the 73 islet autoantibody-negative patients with HbA_1c <7.5% (58 mmol/mol) at diagnosis identified 36 out of 46 (78%) patients with MODY (detection rate 49%). On follow-up, the 46 patients with MODY had excellent glycemic control, with an HbA_1c of 6.4% (47 mmol/mol), with 42 out of 46 (91%) patients not on insulin treatment.

CONCLUSIONS

At diagnosis of pediatric diabetes, absence of all islet autoantibodies and modest hyperglycemia (HbA_1c <7.5% [58 mmol/mol]) should result in testing for GCK, HNF1A, and HNF4A MODY. Testing all 12% patients negative for four islet autoantibodies is an effective strategy for not missing MODY but will result in a lower detection rate. Identifying MODY results in excellent long-term glycemic control without insulin.

Future Roadmaps for Precision Medicine Applied to Diabetes: Rising to the Challenge of Heterogeneity

Precision medicine, the concept that specific treatments can be targeted to groups of individuals with specific genetic, cellular, or molecular features, is a key aspect of modern healthcare, and its use is rapidly expanding. In diabetes, the application of precision medicine has been demonstrated in monogenic disease, where sulphonylureas are used to treat patients with neonatal diabetes due to mutations in ATP-dependent potassium (K_ATP) channel genes. However, diabetes is highly heterogeneous, both between and within polygenic and monogenic subtypes. Making the correct diagnosis and using the correct treatment from diagnosis can be challenging for clinicians, but it is crucial to prevent long-term morbidity and mortality. To facilitate precision medicine in diabetes, research is needed to develop a better understanding of disease heterogeneity and its impact on potential treatments for specific subtypes. Animal models have been used in diabetes research, but they are not translatable to humans in the majority of cases. Advances in molecular genetics and functional laboratory techniques and availability and sharing of large population data provide exciting opportunities for human studies. This review will map the key elements of future diabetes research in humans and its potential for clinical translation to promote precision medicine in all diabetes subtypes.

A genetic diagnosis of maturity-onset diabetes of the young (MODY): experiences of patients and family members

AIMS

Genetic testing for maturity-onset diabetes of the young (MODY) facilitates a correct diagnosis, enabling treatment optimization and allowing monitoring of asymptomatic family members. To date, the majority of people with MODY remain undiagnosed. To identify patients' needs and areas for improving care, this study explores the experiences of patients and family members who have been genetically tested for MODY.

METHODS

Fourteen semi-structured interviews with patients and the parents of patients, and symptomatic and asymptomatic family members were conducted. Atlas.ti was used for thematic analysis.

RESULTS

Most people with MODY were initially misdiagnosed with Type 1 or Type 2 diabetes; they had been seeking for the correct diagnosis for a long time. Reasons for having a genetic test included reassurance, removing the uncertainty of developing diabetes (in asymptomatic family members) and informing relatives. Reasons against testing were the fear of genetic discrimination and not having symptoms. Often a positive genetic test result did not come as a surprise. Both patients and family members were satisfied with the decision to get tested because it enabled them to adjust their lifestyle and treatment accordingly. All participants experienced a lack of knowledge of MODY among healthcare professionals, in their social environment and in patient organizations. Additionally, problems with the reimbursement of medical expenses were reported.

CONCLUSIONS

Patients and family members are generally positive about genetic testing for MODY. More education of healthcare professionals and attention on the part of diabetes organizations is needed to increase awareness and optimize care and support for people with MODY.

Controversies on how diabetes is diagnosed

PURPOSE OF REVIEW

To evaluate the controversial aspects of diabetes diagnosis.

RECENT FINDINGS

Within the past 2 years, revised guidelines for the diagnosis of diabetes have been issued which endorse the use of the hemoglobin A1C as a diagnostic test, in addition to the previously recommended tests. Updated diagnostic criteria for gestational diabetes were also published in the same period. Recent publications on the current role of oral glucose tolerance tests and diagnosis of diabetes in the acutely ill are sparse. There are new recommendations regarding the use of genetic testing and antibody testing in establishing the cause of diabetes.

SUMMARY

The inclusion of A1C as a diagnostic test has many advantages including reproducibility of the test and convenience, but there are situations where the test is unreliable and it misses many individuals who would have been diagnosed by plasma glucose testing. The diagnostic threshold of 6.5% for the A1C remains controversial. There is still no consensus on the best approach to diagnose gestational diabetes. The role of the oral glucose tolerance test seems to be diminishing. Diagnosis of diabetes in acute illness is aided by A1C testing. Genetic and autoantibody testing in specific situations offer diagnostic and therapeutic utility.