Diabetes Care Disparities in Long-standing Type 1 Diabetes in Canada and the U.S.: A Cross-sectional Comparison

The association between physical activity time and neuropathy in longstanding type 1 diabetes: A cross-sectional analysis of the Canadian study of longevity in type 1 diabetes

AIM

Physical activity (PA) is recommended to improve glycemic control in T1D; however, the effect of PA on distal symmetric polyneuropathy (DSPN) and cardiac autonomic function in longstanding T1D is unknown.

METHODS

Data from 75 participants were collected as part of the Canadian Study of Longevity in T1D. Participants completed a physical exam, medical history, extensive complications phenotyping and reported their daily PA from the preceding 12-months. Pearson and Spearman correlations were used to assess PA time and complications variables. Linear regression was used to test associations between PA time, neurological and electrophysiological measures. Univariable regression was used to indicate the change in the given independent variables associated with a 30-min increase in PA per week.

RESULTS

Participants were 66 ± 8 years old with diabetes duration of 54 [52,58] years, HbA_1c was 7.3 ± 0.8, 65(89%) had DSPN. Weekly PA time was 156 ± 132 min, and 35(47%) reported ≧150 min/week. Participants with DSPN reported lower PA time compared to individuals without DSPN (141 ± 124 min/week vs. 258 ± 129 min/week; p = 0.015). PA time was associated with better cooling detection threshold (r = 0.24; p = 0.043), peroneal and sural amplitude (r = 0.36; p = 0.0017, r_s = 0.26; p = 0.024) and conduction velocity (r_s = 0.28; p = 0.015, r = 0.23; p = 0.050). Linear regression adjusting for age and HbA1c, showed that for each 30-min of PA there was a 0.09mv higher peroneal amplitude (p = 0.032) and 0.048 ms lower peroneal F-wave latency (p = 0.022).

CONCLUSION

In longstanding T1D, PA time is associated with superior large nerve fibre function in the lower limbs and some better measures of small nerve fibre function.

"Clinical status and mortality in older adults with type 1 diabetes: Results from a public health system"

AIM

To evaluate clinical status and mortality in older adults with long-standing type 1 diabetes mellitus (T1D).

METHODS

Cross-sectional analysis of all patients with T1D for 50 years or more from a cohort followed since 2010 at Castilla-La Mancha Public Health Service (Spain). Primary outcome was HbA1c change during the follow-up (2010-2020 period). Secondary outcomes included evaluation of insulin and continuous glucose monitoring (CGM) use, cardiovascular risk factors (CVRF), diabetes chronic complications and mortality.

RESULTS

A total of fifty-five T1D patients were analysed. Mean age was 69.5 ± 8.3 yrs. and T1D duration of 54.7 ± 4.7 yrs. We detected a HbA1c reduction of -0.5% (-6 mmol/mol) [95% CI -0.1, -0.9 (-2, -10); P = 0.016]. CGM was used by 26% of the patients. More patients suffered from hypertension and obesity in 2020 (66% vs. 78%, P = 0.016; and 26% vs. 31%, P = 0.016; respectively). An increase of diabetic polyneuropathy was detected (45% vs. 67%, P = 0.008). Rate of mortality was higher among patients with long-standing T1D (26% vs. 3.5%, P < 0.001), due to cardiovascular disease (57%).

CONCLUSIONS

Older adults with long-standing T1D patients improved glycemic control although a worsening of CVRF and higher mortality rateweredetected.

Presence and Determinants of Cardiovascular Disease and Mortality in Individuals With Type 1 Diabetes of Long Duration: The FinnDiane 50 Years of Diabetes Study

OBJECTIVE

The aim of this study was to determine the incidence of cardiovascular disease (CVD) and mortality as well as their risk factors in type 1 diabetes (T1D) of >50 years' duration.

RESEARCH DESIGN AND METHODS

From 5,396 individuals included in the Finnish Diabetic Nephropathy Study (FinnDiane), 729 diagnosed in 1967 or earlier survived with T1D for >50 years. In this FinnDiane 50-year cohort, cumulative incidence of CVD events was assessed from the diagnosis of diabetes, and the excess CVD risk, compared with 12,710 matched individuals without diabetes. In addition, risk factors for different types of CVD (both nonfatal and fatal) and mortality were analyzed, and cause-specific hazard ratios were estimated during a median follow-up of 16.6 years from the baseline visit (median duration of diabetes 39 years at baseline).

RESULTS

In individuals with diabetes duration of >50 years, the 60-year cumulative incidence of CVD from the diagnosis of diabetes was 64.3% (95% CI 62.5-66.0). Compared with individuals without diabetes, the standardized incidence ratio for CVD was 7.4 (6.5-8.3); in those with normoalbuminuria, it was 4.9 (4.0-5.9). Mean HbA_1c and HbA_1c variability, dyslipidemia, BMI, kidney disease, age, and diabetes duration were the variables associated with incident CVD. In particular, HbA_1c was associated with peripheral artery disease (PAD). The standardized mortality ratio compared with the Finnish background population was 3.2 (2.8-3.7). The factors associated with mortality were diabetes duration, increased HbA_1c variability, inflammation, insulin resistance, kidney disease, and PAD.

CONCLUSIONS

Individuals with T1D of very long duration are at a high risk of CVD. In addition, throughout the lifespan, optimal glycemic control remains central to CVD and excess mortality prevention.

Discoveries from the study of longstanding type 1 diabetes

Award programmes that acknowledge the remarkable accomplishments of long-term survivors with type 1 diabetes have naturally evolved into research programmes to determine the factors associated with survivorship and resistance to chronic complications. In this review, we present an overview of the methodological sources of selection bias inherent in survivorship research (selection of those with early-onset diabetes, incidence-prevalence bias and bias from losses to follow-up in cohort studies) and the breadth and depth of literature focusing on this special study population. We focus on the learnings from the study of longstanding type 1 diabetes on discoveries about the natural history of insulin production loss and microvascular complications, and mechanisms associated with them that may in future offer therapeutic targets. We detail descriptive findings about the prevalence of preserved insulin production and resistance to complications, and the putative mechanisms associated with such resistance. To date, findings imply that the following mechanisms exist: strategies to maintain or recover beta cells and their function; activation of specific glycolytic enzymes such as pyruvate kinase M2; modification of AGE production and processing; novel mechanisms for modification of renin-angiotensin-aldosterone system activation, in particular those that may normalise afferent rather than efferent renal arteriolar resistance; and activation and modification of processes such as retinol binding and DNA damage checkpoint proteins. Among the many clinical and public health insights, research into this special study population has identified putative mechanisms that may in future serve as therapeutic targets, knowledge that likely could not have been gained without studying long-term survivors.

Protection from neuropathy in extreme duration type 1 diabetes

A proportion of individuals with type 1 diabetes mellitus for more than 50 years (medallists) may be protected from developing nephropathy, retinopathy and neuropathy. Detailed neuropathy phenotyping was undertaken in a cohort of 33 medallists aged 63.7 ± 1.4 years with diabetes for 58.5 ± 0.8 years and HbA1c of 65.9 ± 2.1 mmol/mmol. Medallists had a significantly higher HbA1c (P < .001), lower estimated glomerular filtration rate (eGFR) (P = .005) and higher albumin creatinine excretion ratio (ACR) (P = .01), but a lower total cholesterol (P < .001), triacylglycerols (P = .001), low density lipoprotein‐cholesterol (P < .001) and higher high density lipoprotein‐cholesterol (P = .03), compared to controls. Twenty‐four percent of participants were identified as “escapers” without confirmed diabetic neuropathy. They had a lower neuropathy symptom profile (P = .002), vibration perception threshold (P = .02), warm threshold (P = .05), higher peroneal amplitude (P = .005), nerve conduction velocity (P = .03), heart rate variability (P = .001), corneal nerve fibre density (P = 0.001), branch density (P < .001) and length (P = .001), compared to medallists with diabetic neuropathy. Escapers had a shorter duration of diabetes (P = .006), lower alcohol consumption (P = .04), lower total cholesterol (P = .04) and LDL (P = .02), higher eGFR (P = .001) and lower ACR (P < .001). Patients with extreme duration diabetes without diabetic neuropathy have a comparable HbA1c, blood pressure and body mass index, but a more favourable lipid profile and consume less alcohol compared to those with diabetic neuropathy.

The Prevalence of Autoimmune Diseases in Longstanding Diabetes: Results from the Canadian Study of Longevity in Adults with Type 1 Diabetes

OBJECTIVE

We aimed to determine the prevalence of autoimmune diseases (e.g. thyroid disease, celiac disease, etc) in Canadians with longstanding type 1 diabetes (T1D) and to explore sex-specific differences and the association with complications.

METHODS

Cross-sectional data were analyzed in an exploratory secondary analysis from the Canadian Study of Longevity in Type 1 Diabetes, a nationwide registry of people with T1D of at least 50 years' duration. In total, 374 participants provided self-reported questionnaire data and physician-reported laboratory results. Student's t-test, the Wilcoxon rank-sum test, the χ² test and logistic regression were used to identify associations with autoimmune diseases.

RESULTS

The 374 participants had a median T1D duration of 53 years (interquartile range, 51 to 58) and a median age of onset of 11 years (6 to 16), and 57.1% were females. Females had a greater prevalence of autoimmune diseases (60.6% vs 34.4%, p<0.001). Thyroid disease was most prevalent (41%, 153/374), especially in females (51.6% vs 26.9%), and the prevalence of 1 or more autoimmune disease was 49.3% (184/374). Autoimmune disease was associated with lower odds of cardiovascular disease (CVD)-odds ratio [OR] 0.61, 95% confidence interval [CI] 0.37 to 1.00 for thyroid autoimmune disease and OR 0.34 (95% CI 0.12 to 0.93) for nonthyroid autoimmune disease, both compared to those without autoimmune disease (p=0.033). Autoimmune diseases were not associated with the presence of nephropathy, neuropathy or retinopathy.

CONCLUSIONS

Lifetime risk of autoimmune disease in longstanding T1D approaches 50%, is greater in females and is driven by thyroid disease. The probability of diabetes complications, such as CVD, was lower in those with autoimmune disease, which was driven mostly by nonthyroid autoimmune diseases.

Factors associated with resistance to complications in long-standing type 1 diabetes in China

OBJECTIVE

Type 1 diabetes (T1DM) is associated with a higher risk of premature death, but there are factors in certain patients with T1DM that protect them from complications and premature death. These factors had not been identified in non-Caucasian populations, so we aimed to identify factors that protect against the development of diabetic nephropathy (DN) and diabetic retinopathy (DR) in long-standing T1DM in China

METHODS

Ninety-five T1DM patients with >30 years’ duration of diabetes were enrolled in this nationwide study. Differences between groups of patients with and without complications were compared, and multivariable regression analysis was used to evaluate the relationships between candidate protective factors and the development of DN or DR.

RESULTS

Thirty of the participants did not have DN and the same amount did not have DR. 6/52 of participants without DN were from a rural area, whereas 11/28 of participants with DN had been born in a rural area (P = 0.005). Systolic blood pressure (SBP) was higher in participants with DN (135 ± 26 mmHg vs 121 ± 13 mmHg; P = 0.002). In participants without DR, 27/30 were married or cohabitating, and only 3/30 were single, never married, or widowed, but for those with proliferative DR (PDR), 13/26 had been married (P = 0.003). A rural or urban origin and SBP were associated with DN in the multivariable analysis.

CONCLUSION

we have shown that higher socioeconomic status, indicated by birth in an urban area, and being married or cohabitating, are accompanied by better blood pressure control and a lower risk of microvascular complications in Chinese patients with long-standing T1DM. These findings illustrate the importance of improving care for patients with T1DM in China.

Synthesis and evaluation of anticancer, antiphospholipases, antiproteases, and antimetabolic syndrome activities of some 3H-quinazolin-4-one derivatives

Some new 3H-quinazolin-4-one derivatives were synthesised and screened for anticancer, antiphospholipases, antiproteases, and antimetabolic syndrome activities. Compound 15d was more potent in reducing the cell viabilities of HT-29 and SW620 cells lines to 38%, 36.7%, compared to 5-FU which demonstrated cell viabilities of 65.9 and 42.7% respectively. The IC50 values of 15d were ∼20 µg/ml. Assessment of apoptotic activity revealed that 15d decreased the cell viability by down regulating Bcl2 and BclxL. Moreover, compounds, 8j, 8d/15a/15e, 5b, and 8f displayed lowered IC50 values than oleanolic acid against proinflammatory isoforms of hGV, hG-X, NmPLA2, and AmPLA2. In addition, 8d, 8h, 8j, 15a, 15b, 15e, and 15f showed better anti-α-amylase than quercetin, whereas 8g, 8h, and 8i showed higher anti-α-glucosidase activity than allopurinol. Thus, these compounds can be considered as potential antidiabetic agents. Finally, none of the compounds showed higher antiproteases or xanthine oxidase activities than the used reference drugs.

Glucose Management and the Sex Difference in Excess Cardiovascular Disease Risk in Long-Duration Type 1 Diabetes

PURPOSE OF REVIEW

The protection against CVD observed in women compared to men in the general population is essentially erased in type 1 diabetes. This review will discuss evidence regarding the role of glucose management on CVD risk by sex, with a particular focus on studies of long-duration type 1 diabetes of > 20 years.

RECENT FINDINGS

Across studies, women with type 1 diabetes have similar or worse glycemic control compared to men, despite higher rates of intensive insulin therapy. The association between HbA1c and CVD risk does not seem to differ by sex, but few studies have reported on sex-specific analyses. Beyond HbA1c, there is a lack of published data regarding the relationship between other aspects of glucose management and CVD risk by sex in type 1 diabetes. Glucose management factors do not seem to directly account for the increased CVD risk in women with type 1 diabetes, but may influence other risk factors that play a more direct role.

Bone mineral density in patients with longstanding type 1 diabetes: Results from the Canadian Study of Longevity in Type 1 Diabetes

AIM

It is currently unclear if longstanding type 1 diabetes (T1D) affects bone mineral density (BMD).

METHODS

BMD measured by dual-energy X-ray absorptiometry and history of fragility fracture was determined in 75 T1D participants with ≥50 years of diabetes duration and 75 age- and sex-matched non-diabetic controls. BMD T-scores were determined for the lumbar spine (LS), total hip (TH) and femoral neck (FN).

RESULTS

T1D participants had median diabetes duration of 54 [52, 58] years, 41 (55%) were females, and mean A_1c was 7.3 ± 0.8%. T1D females had higher LS T-scores compared to female controls (-0.3 ± 1.2 vs. -1.1 ± 1.4, p = 0.014), lower FN T-scores (-1.5 ± 1.0 vs. -1.2 ± 0.9, p = 0.042) and more fragility fractures (7 (17%) vs. 1 (2%), p = 0.021). In T1D, higher A1c was associated with higher adjusted odds of fragility fracture (p = 0.006). T1D males and controls showed no difference in BMD or fractures.

CONCLUSIONS

There were no substantial differences in T-score between T1D and matched controls; however, T1D females showed higher BMD at the LS and possibly paradoxically higher fragility fractures compared to matched controls. These findings suggest that lower T-scores may not be associated with a history of fragility fracture in females with longstanding T1D and that other factors should be investigated.

Misdiagnosis and Diabetic Ketoacidosis at Diagnosis of Type 1 Diabetes: Patient and Caregiver Perspectives

IN BRIEF Diabetic ketoacidosis (DKA) is a life-threatening complication that frequently occurs at diagnosis of type 1 diabetes, occurs more commonly when a patient is misdiagnosed, is the leading cause of death in children with type 1 diabetes, and is associated with worse long-term outcomes. Our retrospective online survey found that 25% of all participants were misdiagnosed and that misdiagnosis was associated with an 18% increased risk for DKA compared to those correctly diagnosed. Adult providers should consider type 1 diabetes when diagnosing type 2 diabetes, and pediatric providers should rule out type 1 diabetes when a patient reports nonspecific viral symptoms.

Estimating GFR by Serum Creatinine, Cystatin C, and β2-Microglobulin in Older Adults: Results From the Canadian Study of Longevity in Type 1 Diabetes

INTRODUCTION

Glomerular filtration rate (GFR) is routinely used for clinical assessment of kidney function. However, the accuracy of estimating equations in older adults is uncertain.

METHODS

In 66 adults with ≥50 years type 1 diabetes (T1D) duration and 73 nondiabetic controls from age/sex-matched subgroups (65 ± 8 years old and 77[55%] were women) we evaluated the performance of estimated GFR (eGFR) by creatinine (Modification of Diet and Renal Disease [MDRD], Chronic Kidney Disease-Epidemiology [CKD-EPI]cr), cystatin C (CKD-EPIcys, CKD-EPIcr-cys), and β2-microglobulin (β2M) compared with measured GFR by inulin clearance (mGFR). Performance was evaluated using metrics of bias (mean difference), precision (SD), and accuracy (proportion of eGFR that differed by >20% of mGFR).

RESULTS

Mean mGFR was 104 ± 18 ml/min per 1.73 m2 (range: 70-154 ml/min per 1.73 m2) and was not different between T1D and controls (103 ± 17 vs. 105 ± 19 ml/min per 1.73 m2, P = 0.39). All equations significantly underestimated mGFR (bias: -15 to -30 ml/min per 1.73 m2, P < 0.001 for all comparisons) except for β2M, which had bias of 1.9 ml/min per 1.73 m2 (P = 0.61). Bias was greatest in cystatin C-based equations. Precision was lowest for β2M (SD: 43.5 ml/min per 1.73 m2, P < 0.001 for each comparison). Accuracy was lowest for CKD-EPIcysC (69.1%, P < 0.001 for each comparison). Cystatin C-based equations demonstrated greater bias and lower accuracy in older age subgroups (<60, 60-69, ≥70 years). All equations demonstrated greater bias across higher ranges of mGFR (60-89, 90-119, ≥120 ml/min per 1.73 m2). Results were similar between T1D and controls except that β2M had lower performance in T1D.

CONCLUSION

Better estimates of GFR in older adults are needed for research and clinical practice, as this subgroup of the population has an amplified risk for the development of chronic kidney disease (CKD) that requires accurate GFR estimation methods.

Poorer Quality of Life and Treatment Satisfaction is Associated with Diabetic Retinopathy in Patients with Type 1 Diabetes without Other Advanced Late Complications

Diabetic retinopathy (DR) may potentially cause vision loss and affect the patient’s quality of life (QoL) and treatment satisfaction (TS). Using specific tools, we aimed to assess the impact of DR and clinical factors on the QoL and TS in patients with type 1 diabetes. This was a cross-sectional, two-centre study. A sample of 102 patients with DR and 140 non-DR patients were compared. The Audit of Diabetes-Dependent Quality of Life (ADDQoL-19) and Diabetes Treatment Satisfaction Questionnaire (DTSQ-s) were administered. Data analysis included bivariate and multivariable analysis. Patients with DR showed a poorer perception of present QoL (p = 0.039), work life (p = 0.037), dependence (p = 0.010), and had a lower average weighted impact (AWI) score (p = 0.045). The multivariable analysis showed that DR was associated with a lower present QoL (p = 0.040), work life (p = 0.036) and dependence (p = 0.016). With regards to TS, DR was associated with a higher perceived frequency of hypoglycaemia (p = 0.019). In patients with type 1 diabetes, the presence of DR is associated with a poorer perception of their QoL. With regard to TS, these subjects also show a higher perceived frequency of hypoglycaemia.

Cognitive Function Deficits Associated With Long-Duration Type 1 Diabetes and Vascular Complications

OBJECTIVE

Patients with type 1 diabetes now live long enough to experience cognitive decline. During middle age, they show mild cognitive deficits, but it is unknown whether severity increases with aging or whether cognitive profiles are similar to those of age-matched peers with and without diabetes.

RESEARCH DESIGN AND METHODS

We tested and compared cognition in 82 individuals with 50 or more years of type 1 diabetes (Medalists), 31 age-matched individuals with type 2 diabetes, and 30 age-matched control subjects without diabetes. Medical histories and biospecimens were collected. We also evaluated the association of complications with cognition in Medalists only.

RESULTS

Compared with control subjects, both individuals with type 1 diabetes and individuals with type 2 diabetes performed worse on immediate and delayed recall (P ≤ 0.002) and psychomotor speed in both hands (P ≤ 0.01) and showed a trend toward worse executive function (P = 0.05). In Medalists, cardiovascular disease was associated with decreased executive function and proliferative diabetic retinopathy with slower psychomotor speed.

CONCLUSIONS

Both patients with type 1 and patients with type 2 diabetes showed overall worse cognition than control subjects. Further, in Medalists, a relationship between complications and cognition was seen. Although both groups with diabetes showed similar deficit patterns, the underlying mechanisms may be different. Now that patients with type 1 diabetes are living longer, efforts should be made to evaluate cognition and to identify modifying behaviors to slow decline.

Sex differences in neuropathic pain in longstanding diabetes: Results from the Canadian Study of Longevity in Type 1 Diabetes

AIM

Neuropathy and neuropathic pain are common complications of type 1 diabetes (T1D). We aimed to determine if sex-specific differences in neuropathic pain are present in adults with longstanding T1D.

METHODS

Canadians with ≥50 years of T1D (n = 361) completed health history questionnaires that included assessment of neuropathy (defined by Michigan Neuropathy Screening Instrument questionnaire components ≥3; NEUROPATHY_MNSI-Q) and neuropathic pain. Multivariable logistic regression was used to determine sex-differences in neuropathic pain controlling for neuropathy.

RESULTS

Participants had mean age 66 ± 9 years, median diabetes duration 53[51,58] years, mean HbA1c 7.5 ± 1.0%, and 207(57%) were female. Neuropathic pain was present in 128(36%) of all participants, more prevalent among those with NEUROPATHY_MNSI-Q compared to those without [96(63%) vs. 31(15%), p < 0.001], and more prevalent in females compared to males [87(42%) vs. 41(27%), p = 0.003]. Independent of the presence of NEUROPATHY_MNSI-Q and other factors, female sex was associated with the presence of neuropathic pain [OR 2.68 (95% CI 1.4-5.0), p = 0.002].

CONCLUSIONS

We demonstrated a novel sex-specific difference in neuropathic pain in females compared to males with longstanding T1D, independent of the presence of neuropathy. Further research using more objective measures of neuropathy than the MNSI is justified to further understand this sex-specific difference.