Altered responses to hypoglycemia of healthy elderly people

Associations between clustering of hypoglycemic symptoms, psychological traits, and problem-solving abilities in adults with type 1 diabetes: baseline data analysis of the PR-IAH study

Background

Precision medicine in diabetes care requires a dedicated focus on hypoglycemic symptoms. This study explored the associations between clustering of hypoglycemic symptoms, psychological characteristics, and problem-solving capabilities in adults with type 1 diabetes (T1D).

Methods

A total of 251 adults with T1D participated in this survey. Hierarchical clustering was used to analyze 11 hypoglycemic symptoms (Edinburgh scale). The data included diabetic complications, fear of hypoglycemia, depressive symptoms, hypoglycemia problem-solving scale (HPSS), and treatment details. For predicting clusters and identifying feature importance, we utilized a machine learning approach.

Results

Three distinct clusters were observed; individuals not sensitive to autonomic or neuroglycopenic symptoms (cluster 1, n = 138), those sensitive to both autonomic and neuroglycopenic symptoms (cluster 2, n = 19), and those sensitive to autonomic but not neuroglycopenic symptoms (cluster 3, n = 94). Compared to cluster 1, individuals from clusters 2 and 3 were of younger age, had higher fear of hypoglycemia, increased depressive symptoms, and greater use of continuous subcutaneous insulin infusion. Cluster 2 displayed enhanced HPSS scores, indicating better detection control and a more proactive approach to seeking preventive strategies than cluster 1. The accuracy for classifying into 3 clusters using machine learning was 88.2%. The feature importance of random forest model indicated that hunger, shaking, palpitation, sweating, and confusion were the top five important factors for predicting clusters.

Conclusion

This study identified three distinct clusters of adults with T1D. These findings may provide valuable insights for diabetes professionals seeking to educate these individuals on how to manage hypoglycemia effectively.

Trial registration

University Hospital Medical Information Network (UMIN) Center: UMIN000039475); approval date: February 13, 2020.

Ageing well with diabetes: the role of technology

Over the past two decades there has been a substantial rise in the adoption of diabetes therapeutic technology among children, adolescents and younger adults with type 1 diabetes, and its use is now also advocated for older individuals. Older people with diabetes are more prone to experience hypoglycaemia because of numerous predisposing factors and are at higher risk of hypoglycaemic events requiring third-party assistance as well as other adverse sequelae. Hypoglycaemia may also have long-term consequences, including cognitive impairment, frailty and disability. Diabetes in older people is often characterised by marked glucose variability related to age-associated changes such as variable appetite and levels of physical activity, comorbidities and polypharmacotherapy. Preventing hypoglycaemia and mitigating glucose excursions may have considerable positive impacts on physical and cognitive function and general well-being and may even prevent or improve frailty. Technology for older people includes continuous glucose monitoring systems, insulin pumps, automated insulin delivery systems and smart insulin pens. Clinical trials and real-world studies have shown that older people with diabetes benefit from technology in terms of glucose management, reductions in hypoglycaemic events, emergency department attendance and hospital admissions, and improvement in quality of life. However, ageing may bring physical impairments and other challenges that hinder the use of technology. Healthcare professionals should identify older adults with diabetes who may benefit from therapeutic technology and then adopt an individualised approach to education and follow-up for individuals and their caregivers. Future research should explore the impact of diabetes technology on outcomes relevant to older people with diabetes.

Glycaemic thresholds for counterregulatory hormone and symptom responses to hypoglycaemia in people with and without type 1 diabetes: a systematic review

AIM/HYPOTHESIS

The physiological counterregulatory response to hypoglycaemia is reported to be organised hierarchically, with hormone responses usually preceding symptomatic awareness and autonomic responses preceding neuroglycopenic responses. To compare thresholds for activation of these responses more accurately between people with or without type 1 diabetes, we performed a systematic review on stepped hyperinsulinaemic-hypoglycaemic glucose clamps.

METHODS

A literature search in PubMed and EMBASE was conducted. We included articles published between 1980 and 2018 involving hyperinsulinaemic stepped hypoglycaemic glucose clamps among people with or without type 1 diabetes. Key exclusion criteria were as follows: data were previously published; other patient population; a clamp not the primary intervention; and an inadequate clamp description. Glycaemic thresholds for counterregulatory hormone and/or symptom responses to hypoglycaemia were estimated and compared using generalised logrank test for interval-censored data, where the intervals were either extracted directly or calculated from the data provided by the study. A glycaemic threshold was defined as the glucose level at which the response exceeded the 95% CI of the mean baseline measurement or euglycaemic control clamp. Because of the use of interval-censored data, we described thresholds using median and IQR.

RESULTS

A total of 63 articles were included, whereof 37 papers included participants with type 1 diabetes (n=559; 67.4% male sex, aged 32.7±10.2 years, BMI 23.8±1.4 kg/m²) and 51 papers included participants without diabetes (n=733; 72.4% male sex, aged 31.1±9.2 years, BMI 23.6±1.1 kg/m²). Compared with non-diabetic control individuals, in people with type 1 diabetes, the median (IQR) glycaemic thresholds for adrenaline (3.8 [3.2-4.2] vs 3.4 [2.8-3.9 mmol/l]), noradrenaline (3.2 [3.2-3.7] vs 3.0 [2.8-3.1] mmol/l), cortisol (3.5 [3.2-4.2]) vs 2.8 [2.8-3.4] mmol/l) and growth hormone (3.8 [3.3-3.8] vs. 3.2 [3.0-3.3] mmol/l) all occurred at lower glucose levels in people with diabetes than in those without diabetes (all p≤0.01). Similarly, although both autonomic (median [IQR] 3.4 [3.4-3.4] vs 3.0 [2.8-3.4] mmol/l) and neuroglycopenic (median [IQR] 3.4 [2.8-N/A] vs 3.0 [3.0-3.1] mmol/l) symptom responses were elicited at lower glucose levels in people with type 1 diabetes, the thresholds for autonomic and neuroglycopenic symptoms did not differ for each individual subgroup.

CONCLUSIONS/INTERPRETATION

People with type 1 diabetes have glycaemic thresholds for counterregulatory hormone and symptom responses at lower glucose levels than people without diabetes. Autonomic and neuroglycopenic symptoms responses are generated at about similar levels of hypoglycaemia. There was a considerable variation in the methodology of the articles and the high insulin doses in most of the clamps may affect the counterregulatory responses.

FUNDING

This article has received funding from the Innovative Medicines Initiative 2 Joint Undertaking (JU) under grant agreement no. 777460.

REGISTRATION

This systematic review is registered in PROSPERO (CRD42019120083).

Type 2 diabetes mellitus in older adults: clinical considerations and management

The past 50 years have seen a growing ageing population with an increasing prevalence of type 2 diabetes mellitus (T2DM); now, nearly half of all individuals with diabetes mellitus are older adults (aged ≥65 years). Older adults with T2DM present particularly difficult challenges. For example, the accentuated heterogeneity of these patients, the potential presence of multiple comorbidities, the increased susceptibility to hypoglycaemia, the increased dependence on care and the effect of frailty all add to the complexity of managing diabetes mellitus in this age group. In this Review, we offer an update on the key pathophysiological mechanisms associated with T2DM in older people. We then evaluate new evidence relating particularly to the effects of frailty and sarcopenia, the clinical difficulties of age-associated comorbidities, and the implications for existing guidelines and therapeutic options. Our conclusions will focus on the effect of T2DM on an ageing society.

Challenges and Strategies for Inpatient Diabetes Management in Older Adults

Adults older than 65 years of age are the fastest growing segment of the U.S. population. Aging is also one of the most important risk factors for diabetes, and about one-third of all individuals with diabetes are in this age-group. Older people with diabetes are more likely to have comorbidities such as hypertension, ischemic heart disease, chronic kidney disease, and cognitive impairment, which lead to higher rates of hospital admissions compared with individuals without diabetes. Professional organizations have recommended patient-centric individualized glycemic reduction approaches, with an emphasis on potential harms of intensive glycemic control and overtreatment in older adults. Insulin therapy remains a mainstay of diabetes management in the inpatient setting regardless of patients' age; however, there is uncertainty about optimal glycemic targets during the hospital stay. Increasing evidence supports selective use of dipeptidyl peptidase-4 inhibitors, alone or in combination with low-dose basal insulin, in older noncritically ill patients with mild to moderate hyperglycemia. This article reviews the prevalence, diagnosis, and monitoring of, and the available treatment strategies for, diabetes among elderly patients in the inpatient setting.

Cognitive dysfunction during hypoglycemia in an elderly subject without diabetes

The aim of the present study was to examine whether an elderly subject without diabetes experiences hypoglycemia during his daily life or after an oral glucose tolerance test (OGTT), and investigate whether hypoglycemic episodes affect cognitive function. The 85-year-old healthy subject, who is a sports enthusiast, showed lower than normal (< 80 mg/dl) blood glucose levels on two occasions over 6 days in the early morning. The subject also experienced hypoglycemic episodes and blood glucose levels of 65 and 74 mg/dl, respectively, during the 6-h OGTT given after a 13-h fast. Cognitive function, as assessed using a numeracy test and a driving simulator test, deteriorated during the hypoglycemic episodes but recovered 0.5 h after ingestion of a confectionary product (two pieces of Dorayaki containing 247 kcal and 51.5 g of carbohydrate each). Cognitive dysfunction caused by mild hypoglycemia can be involved in a part of traffic accidents in elderly drivers.

Impact of drugs on hypoglycaemia in hospitalised patients

Objectives

Hospital admission rates for hypoglycaemia now exceed those for hyperglycaemias among older adults. A growing number of reports associating hypoglycaemia with non-antidiabetic drugs have been published. Clinical pharmacists are often faced with hypoglycaemia in patients taking multiple medications. This study assessed the potential relationship between prescribed drugs and episodes of hypoglycaemia during hospitalisation.

Methods

Point-of-care blood glucose values and prescribed drugs were analysed in patients admitted to a regional hospital. Hypoglycaemia cases were defined as patients with at least one hypoglycaemic event (random glucose value ≤3.9 mmol/L), and normoglycaemic cases as those with random glucose concentrations within the range of 4.5-5.8 mmol/L. Analyses were carried out using multivariate logistic regressions and Cox proportional hazard models.

Results

373 patients (53% males; median age=74 years) were included in the analysis and of these, 64 (17%) had at least one hypoglycaemic event. Patients who experienced a hypoglycaemic event had a longer length of stay (median=10 vs 7 days, p<0.01) and a higher rate of antidiabetic drugs prescription (83% vs 37%, p<0.01). The number of non-antidiabetic drugs was associated with an increased risk of hypoglycaemia during hospitalisation (HR 2.3, 95% CI 1.4 to 4, p<0.01). After adjusting by confounders, heparin and pantoprazole were found to be associated with hypoglycaemia.

Conclusions

The relationship between hypoglycaemia and polypharmacy reinforces the advice to limit polymedication as much as possible, especially in elderly patients. This result underlines the potential involvement of clinical pharmacists with the aim to reduce the risk of hypoglycaemia during hospitalisation.

Impaired Cortisol and Growth Hormone Counterregulatory Responses among Severe Hypoglycemic Patients with Type 2 Diabetes Mellitus

BACKGROUND

Elevated levels of cortisol and growth hormone are critical counterregulatory responses to severe hypoglycemia. However, the proportion and clinical characteristics of patients with type 2 diabetes mellitus (DM) who fail to show appropriate cortisol and/or growth hormone secretion in response to severe hypoglycemia have not been investigated.

METHODS

We measured plasma cortisol and growth hormone levels in type 2 DM patients with severe hypoglycemia who visited the emergency department between 2006 and 2015.

RESULTS

Of 112 hypoglycemic patients, 23 (20.5%) had an impaired cortisol response (<18 μg/dL) and 82 patients (73.2%) had an impaired growth hormone response (<5 ng/mL). Nineteen patients (17.0%) had impaired responses to both cortisol and growth hormone. The patients with impaired responses of cortisol, growth hormone, and both hormones were significantly older and more likely to be female, and had higher admission rates, lower growth hormone levels, and lower adrenocorticotropic hormone levels than the patients with a normal hormonal response. Multivariate logistic regression analysis indicated that an impaired growth hormone response was significantly associated with advanced age, shorter DM duration, a higher admission rate, and a higher body mass index (BMI). An impaired cortisol response was significantly associated with growth hormone levels. Patients with an impaired growth hormone response had higher admission rates than patients with a normal response.

CONCLUSION

A considerable number of type 2 DM patients had impaired cortisol and/or growth hormone responses to severe hypoglycemia. Advanced age, shorter DM duration, and higher BMI were independently associated with an abnormal growth hormone response.

Diabetes Management in the Elderly

IN BRIEF Older adults with diabetes present unique challenges and require considerations that are not traditionally associated with diabetes management. In this review, we focus on issues that are unique to the older population and provide practical guidance for clincians who care for them.

Global burden of hypoglycaemia-related mortality in 109 countries, from 2000 to 2014: an analysis of death certificates

AIMS/HYPOTHESIS

In the context of increasing prevalence of diabetes in elderly people with multimorbidity, intensive glucose control may increase the risk of severe hypoglycaemia, potentially leading to death. While rising trends of severe hypoglycaemia rates have been reported in some European, North American and Asian countries, the global burden of hypoglycaemia-related mortality is unknown. We aimed to investigate global differences and trends of hypoglycaemia-related mortality.

METHODS

We used the WHO mortality database to extract information on death certificates reporting hypoglycaemia or diabetes as the underlying cause of death, and the United Nations demographic database to obtain data on mid-year population estimates from 2000 to 2014. We calculated crude and age-standardised proportions (defined as number of hypoglycaemia-related deaths divided by total number of deaths from diabetes [i.e. the sum of hypoglycaemia- and diabetes-related deaths]) and rates (hypoglycaemia-related deaths divided by mid-year population) of hypoglycaemia-related mortality and compared estimates across countries and over time.

RESULTS

Data for proportions were extracted from 109 countries (31 had data from all years analysed [2000-2014] available). Combining all countries, the age-standardised proportion of hypoglycaemia-related deaths was 4.49 (95% CI 4.44, 4.55) per 1000 total diabetes deaths. Compared with the overall mean, most Central American, South American and (mainly) Caribbean countries reported higher proportions (five more age-standardised hypoglycaemia-related deaths per 1000 total diabetes deaths in Chile, six in Uruguay, 11 in Belize and 22 in Aruba), as well as Japan (11 more age-standardised hypoglycaemia-related deaths per 1000 total diabetes deaths). In comparison, lower proportions were noted in most European countries, the USA, Canada, New Zealand and Australia. For countries with data available for all years analysed, trend analysis showed a 60% increase in hypoglycaemia-related deaths until 2010 and stable trends onwards. Rising trends were most evident for Argentina, Brazil, Chile, the USA and Japan. Data for rates were available for 105 countries (30 had data for all years analysed [2000-2014] available). Combining all countries, the age-standardised hypoglycaemia-related death rate was 0.79 (95% CI 0.77, 0.80) per 1 million person-years. Most Central American, South American and Caribbean countries similarly reported higher rates of hypoglycaemia-related death, whilst virtually all European countries, the USA, Canada, Japan, New Zealand and Australia reported lower rates compared with the overall mean. Age-standardised rates were very low for most countries (lower than five per 1 million person-years in 89.5% of countries), resulting in small absolute differences among countries. As noted with the proportions analysis, trend analysis showed an overall 60% increase in hypoglycaemia-related deaths until 2010 and stable rate trends onwards; rising rates were particularly evident for Brazil, Chile and the USA.

CONCLUSIONS/INTERPRETATION

Most countries in South America, Central America and the Caribbean showed the highest proportions of diabetes-related deaths attributable to hypoglycaemia and the highest rates of hypoglycaemia-related deaths. Between 2000 and 2014, rising trends were observed in Brazil, Chile and the USA for both rates and proportions of hypoglycaemia-related death, and in Argentina and Japan for proportions only. Further studies are required to unravel the contribution of clinical and socioeconomic factors, difference in diabetes prevalence and heterogeneity of death certification in determining lower rates and proportions of hypoglycaemia-related deaths in high-income countries in Europe, North America and Asia.

DATA AVAILABILITY

Data used for these analyses are available at https://doi.org/10.17632/ndp52fbz8r.1.

Exaggerated glucagon responses to hypoglycemia in women with polycystic ovary syndrome

CONTEXT

Premenopausal women have blunted counter-regulatory hormone responses (CRR) to hypoglycemia compared to men. Postmenopausal women have CRR similar to men; the premenopausal pattern can be restored by estrogen. However, glucagon and pancreatic polypeptide (PP) responses remain lower in postmenopausal women than in men. Since hyperandrogenemia contributes to the metabolic phenotype of polycystic ovary syndrome (PCOS), we hypothesize that CRR to hypoglycemia especially of glucagon and PP is exaggerated in premenopausal women with PCOS compared to premenopausal control women.

STUDY SUBJECTS AND METHODS

Ten obese women with PCOS and 9 control women of similar ethnicity, age and BMI underwent determination of CRR in response to hypoglycemia during 180-min 60mU/m²/min insulin dose hypoglycemic clamp with isotopic assessment of endogenous glucose production (EGP). To assess CRR to hypoglycemia, glucagon, cortisol, growth hormone (GH), epinephrine, norepinephrine, PP, lactate, free fatty acid (FFA), β-hydroxybutyrate, and glycerol levels were sampled at 15-min intervals throughout the clamp.

MAIN FINDINGS

Incremental glucagon levels were ~3-fold higher during hypoglycemia (P=0.03) in PCOS. Postabsorptive, steady-state and incremental GH, cortisol, epinephrine, norepinephrine, PP, FFA, glycerol and β-hydroxybutyrate did not differ. At target glucose levels of ~52mg/dL, insulin mediated glucose disposal (IMGD) was decreased by ~40% (P=0.02) in PCOS, compared to control women, despite ~20% higher steady-state insulin levels (P=0.03). Neither postabsorptive nor steady-state EGP differed. However, postabsorptive lactate levels were ~50% higher (P=0.02). PCOS status (P=0.04) and IMGD (P=0.02) predicted the differential glucagon response to hypoglycemia in separate regression models, however, neither parameter remained an independent predictor in a combined model.

PRINCIPAL CONCLUSIONS

Glucagon responses were increased in PCOS, whereas other CRR did not differ. Women with PCOS were insulin resistant under hypoglycemic conditions and higher postabsorptive lactate levels in PCOS were consistent with this finding. Insulin resistance may have contributed to exaggerated glucagon response to hypoglycemia in PCOS.

Management of Inpatient Hyperglycemia and Diabetes in Older Adults

Adults aged 65 years and older are the fastest growing segment of the U.S. population, and their number is expected to double to 89 million between 2010 and 2050. The prevalence of diabetes in hospitalized adults aged 65-75 years and over 80 years of age has been estimated to be 20% and 40%, respectively. Similar to general populations, the presence of hyperglycemia and diabetes in elderly patients is associated with increased risk of hospital complications, longer length of stay, and increased mortality compared with subjects with normoglycemia. Clinical guidelines recommend target blood glucose between 140 and 180 mg/dL (7.8 and 10 mmol/L) for most patients in the intensive care unit (ICU). A similar blood glucose target is recommended for patients in non-ICU settings; however, glycemic targets should be individualized in older adults on the basis of a patient's clinical status, risk of hypoglycemia, and presence of diabetes complications. Insulin is the preferred agent to manage hyperglycemia and diabetes in the hospital. Continuous insulin infusion in the ICU and rational use of basal-bolus or basal plus supplement regimens in non-ICU settings are effective in achieving glycemic goals. Noninsulin regimens with the use of dipeptidyl peptidase 4 inhibitors alone or in combination with basal insulin have been shown to be safe and effective and may represent an alternative to basal-bolus regimens in elderly patients. Smooth transition of care to the outpatient setting is facilitated by providing oral and written instructions regarding timing and dosing of insulin as well as education in basic skills for home management.

Predictors of hypoglycemia in insulin-treated patients with type 2 diabetes mellitus in Basrah

AIM

To measure the incidence and determinants (predictors) of hypoglycemia among patients with type 2 diabetes mellitus (T2DM) who were on insulin treatment for at least one year.

METHODS

The present study is an out-patients based inquiry about the risk and predictors of hypoglycemia among patients with T2DM seeking care at the Al-Faiha Specialized Diabetes, Endocrine, and Metabolism Center, in Basrah over a period of 7 mo (from 15^th of April, 2013 to 15^th of October, 2013). The data used in the study were based on all detailed interview and selected laboratory investigations. A total of 336 patients could be included in the study.

RESULTS

The incidence of overall hypoglycemia among the studied patients was 75.3% within the last 3 mo preceding the interview. The incidence of hypoglycemia subtypes were 10.2% for severe hypoglycemia requiring medical assistance in the hospital, 44.36% for severe hypoglycemia treated at home by family; this includes both confirmed severe hypoglycemia with an incidence rate of 14.6% and unconfirmed severe hypoglycemia for which incidence rate was 29.76%. Regarding mild self-treated hypoglycemia, the incidence of confirmed mild hypoglycemia was 21.42%, for unconfirmed mild hypoglycemia the incidence rate was 50.0% and for total mild hypoglycemia, the incidence rate was 71.42%. The most important predictors of hypoglycemia were a peripheral residence, increasing knowledge of hypoglycemia symptoms, in availability and increasing frequency of self-monitoring blood glucose, the presence of peripheral neuropathy, higher diastolic blood pressure, and lower Hemoglobin A1c.

CONCLUSION

Hypoglycemia is very common among insulin-treated patients with T2DM in Basrah. It was possible to identify some important predictors of hypoglycemia.

Optimal glycaemic control in elderly people with type 2 diabetes: what does the evidence say?

The global prevalence of type 2 diabetes mellitus (T2DM) is rising in an ageing population through a combination of lifestyle changes and greater longevity. However, by excluding participants aged over 70 years, most major interventional trials on which current diabetes therapeutic guidelines are based have failed to provide specific evidence to support the prescribed management of diabetes in elderly people. While diabetes per se has a significant impact on the elderly person, the side effects of medications, particularly hypoglycaemia, prevent optimisation of diabetes treatment. Hypoglycaemia is associated with significant morbidity, to which elderly people are often more vulnerable because of factors such as the effects of ageing, progressive renal impairment, frailty, polypharmacy and cognitive decline. T2DM is associated with accelerated cognitive decline in some individuals, and recurrent severe hypoglycaemia has been implicated as a potential contributory factor. Although the evidence for selection of appropriate glycaemic targets in elderly patients is sparse, it is now acknowledged that prevention of hypoglycaemia must influence individualisation of treatment goals in this vulnerable group. This should also be reflected by the choice of anti-diabetes agents that are initiated when diet and lifestyle advice is ineffective. Recently developed international guidelines, which have specifically addressed the management of diabetes in elderly people, highlight the importance of a pragmatic management approach rather than attempting to achieve a generic glycated haemoglobin goal and are summarised in this article.

Achieving glycemic control in elderly patients with type 2 diabetes: a critical comparison of current options

The prevalence of type 2 diabetes mellitus (T2DM) is increasing in the elderly. Because of the unique characteristics of elderly people with T2DM, therapeutic strategy and focus should be tailored to suit this population. This article reviews the guidelines and studies related to older people with T2DM worldwide. A few important themes are generalized: 1) the functional and cognitive status is critical for older people with T2DM considering their life expectancy compared to younger counterparts; 2) both severe hypoglycemia and persistent hyperglycemia are deleterious to older adults with T2DM, and both conditions should be avoided when determining therapeutic goals; 3) recently developed guidelines emphasize the avoidance of hypoglycemic episodes in older people, even in the absence of symptoms. In addition, we raise the concern of glycemic variability, and discuss the rationale for the selection of current options in managing this patient population.

Optimal therapy of type 2 diabetes: a controversial challenge

Type 2 diabetes mellitus (T2DM) is one of the most common chronic disorders in older adults and the number of elderly diabetic subjects is growing worldwide. Nonetheless, the diagnosis of T2DM in elderly population is often missed or delayed until an acute metabolic emergency occurs. Accumulating evidence suggests that both aging and environmental factors contribute to the high prevalence of diabetes in the elderly. Clinical management of T2DM in elderly subjects presents unique challenges because of the multifaceted geriatric scenario. Diabetes significantly lowers the chances of "successful" aging, notably it increases functional limitations and impairs quality of life. In this regard, older diabetic patients have a high burden of comorbidities, diabetes-related complications, physical disability, cognitive impairment and malnutrition, and they are more susceptible to the complications of dysglycemia and polypharmacy. Several national and international organizations have delivered guidelines to implement optimal therapy in older diabetic patients based on individualized treatment goals. This means appreciation of the heterogeneity of the disease as generated by life expectancy, functional reserve, social support, as well as personal preference. This paper will review current treatments for achieving glycemic targets in elderly diabetic patients, and discuss the potential role of emerging treatments in this patient population.

Improved glycemic control without hypoglycemia in elderly diabetic patients using the ubiquitous healthcare service, a new medical information system

OBJECTIVE

To improve quality and efficiency of care for elderly patients with type 2 diabetes, we introduced elderly-friendly strategies to the clinical decision support system (CDSS)-based ubiquitous healthcare (u-healthcare) service, which is an individualized health management system using advanced medical information technology.

RESEARCH DESIGN AND METHODS

We conducted a 6-month randomized, controlled clinical trial involving 144 patients aged >60 years. Participants were randomly assigned to receive routine care (control, n = 48), to the self-monitored blood glucose (SMBG, n = 47) group, or to the u-healthcare group (n = 49). The primary end point was the proportion of patients achieving A1C <7% without hypoglycemia at 6 months. U-healthcare system refers to an individualized medical service in which medical instructions are given through the patient's mobile phone. Patients receive a glucometer with a public switched telephone network-connected cradle that automatically transfers test results to a hospital-based server. Once the data are transferred to the server, an automated system, the CDSS rule engine, generates and sends patient-specific messages by mobile phone.

RESULTS

After 6 months of follow-up, the mean A1C level was significantly decreased from 7.8 ± 1.3% to 7.4 ± 1.0% (P < 0.001) in the u-healthcare group and from 7.9 ± 1.0% to 7.7 ± 1.0% (P = 0.020) in the SMBG group, compared with 7.9 ± 0.8% to 7.8 ± 1.0% (P = 0.274) in the control group. The proportion of patients with A1C <7% without hypoglycemia was 30.6% in the u-healthcare group, 23.4% in the SMBG group (23.4%), and 14.0% in the control group (P < 0.05).

CONCLUSIONS

The CDSS-based u-healthcare service achieved better glycemic control with less hypoglycemia than SMBG and routine care and may provide effective and safe diabetes management in the elderly diabetic patients.

Neuroendocrine responses to hypoglycemia

The counterregulatory response to hypoglycemia is a complex and well-coordinated process. As blood glucose concentration declines, peripheral and central glucose sensors relay this information to central integrative centers to coordinate neuroendocrine, autonomic, and behavioral responses and avert the progression of hypoglycemia. Diabetes, both type 1 and type 2, can perturb these counterregulatory responses. Moreover, defective counterregulation in the setting of diabetes can progress to hypoglycemia unawareness. While the mechanisms that underlie the development of hypoglycemia unawareness are not completely known, possible causes include altered sensing of hypoglycemia by the brain and/or impaired coordination of responses to hypoglycemia. Further study is needed to better understand the intricacies of the counterregulatory response and the mechanisms contributing to the development of hypoglycemia unawareness.

Effects of insulin and octreotide on memory and growth hormone in Alzheimer's disease

Both insulin alone and the somatostatin analogue octreotide alone facilitate memory in patients with Alzheimer's disease (AD). Since octreotide inhibits endogenous insulin secretion, the cognitive effects of insulin and octreotide may not be independent. This study tested the individual and interactive effects of insulin and octreotide on memory and plasma growth hormone (GH) levels in older adults. Participants were 16 memory-impaired (AD = 7, amnestic mild cognitive impairment = 9; apolipoprotein E [APOE] epsilon4- [no epsilon4 alleles] = 9, epsilon4+ [1-2 epsilon4 alleles] = 7), and 19 cognitively-intact older adults (APOE epsilon4- = 17, epsilon4+ = 1). On separate days, fasting participants received counterbalanced infusions of: 1) insulin (1 mU.kg(-1).min(-1)) and dextrose to maintain euglycemia; 2) octreotide (150 microg/h); 3) insulin, dextrose, and octreotide; or 4) saline. Story recall was the principal endpoint. Insulin alone facilitated delayed recall for epsilon4- patients, relative to epsilon4+ patients (P = 0.0012). Furthermore, epsilon4- patients with higher Mattis Dementia Rating Scale (DRS) scores had greater octreotide-induced memory facilitation (P = 0.0298). For healthy adults, octreotide facilitated memory (P = 0.0122). Unexpectedly, hyperinsulinemia with euglycemia increased GH levels in healthy controls (P = 0.0299). Thus, insulin and octreotide appear to regulate memory in older adults. APOE epsilon4 genotype modulates responses to insulin and octreotide. Finally, insulin may regulate GH levels during euglycemia.

Hypoglycemia unawareness in older compared with middle-aged patients with type 2 diabetes

OBJECTIVE Older patients with type 2 diabetes are at a particularly high risk for severe hypoglycemic episodes, and experimental studies in healthy subjects hint at a reduced awareness of hypoglycemia in aged humans. However, subjective responses to hypoglycemia have rarely been assessed in older type 2 diabetic patients. RESEARCH DESIGN AND METHODS We tested hormonal, subjective, and cognitive responses (reaction time) to 30-min steady-state hypoglycemia at a level of 2.8 mmol/l in 13 older (> or =65 years) and 13 middle-aged (39-64 years) type 2 diabetic patients. RESULTS Hormonal counterregulatory responses to hypoglycemia did not differ between older and middle-aged patients. In contrast, middle-aged patients showed a pronounced increase in autonomic and neuroglycopenic symptom scores at the end of the hypoglycemic plateau that was not observed in older patients (both P < 0.01). Also, seven middle-aged patients, but only one older participant, correctly estimated their blood glucose concentration to be <3.3 mmol/l during hypoglycemia (P = 0.011). A profound prolongation of reaction times induced by hypoglycemia in both groups persisted even after 30 min of subsequent euglycemia. CONCLUSIONS Our data indicate marked subjective unawareness of hypoglycemia in older type 2 diabetic patients that does not depend on altered neuroendocrine counterregulation and may contribute to the increased probability of severe hypoglycemia frequently reported in these patients. The joint occurrence of hypoglycemia unawareness and deteriorated cognitive function is a critical factor to be carefully considered in the treatment of older patients.

A randomized trial comparing telemedicine case management with usual care in older, ethnically diverse, medically underserved patients with diabetes mellitus: 5 year results of the IDEATel study

CONTEXT Telemedicine is a promising but largely unproven technology for providing case management services to patients with chronic conditions and lower access to care. OBJECTIVES To examine the effectiveness of a telemedicine intervention to achieve clinical management goals in older, ethnically diverse, medically underserved patients with diabetes. DESIGN, Setting, and Patients A randomized controlled trial was conducted, comparing telemedicine case management to usual care, with blinded outcome evaluation, in 1,665 Medicare recipients with diabetes, aged >/= 55 years, residing in federally designated medically underserved areas of New York State. Interventions Home telemedicine unit with nurse case management versus usual care. Main Outcome Measures The primary endpoints assessed over 5 years of follow-up were hemoglobin A1c (HgbA1c), low density lipoprotein (LDL) cholesterol, and blood pressure levels. RESULTS Intention-to-treat mixed models showed that telemedicine achieved net overall reductions over five years of follow-up in the primary endpoints (HgbA1c, p = 0.001; LDL, p < 0.001; systolic and diastolic blood pressure, p = 0.024; p < 0.001). Estimated differences (95% CI) in year 5 were 0.29 (0.12, 0.46)% for HgbA1c, 3.84 (-0.08, 7.77) mg/dL for LDL cholesterol, and 4.32 (1.93, 6.72) mm Hg for systolic and 2.64 (1.53, 3.74) mm Hg for diastolic blood pressure. There were 176 deaths in the intervention group and 169 in the usual care group (hazard ratio 1.01 [0.82, 1.24]). CONCLUSIONS Telemedicine case management resulted in net improvements in HgbA1c, LDL-cholesterol and blood pressure levels over 5 years in medically underserved Medicare beneficiaries. Mortality was not different between the groups, although power was limited. Trial Registration http://clinicaltrials.gov Identifier: NCT00271739.

Nutrition and Aging: Changes in the Regulation of Energy Metabolism With Aging

Changes in energy regulation occur during normal aging and contribute to the common phenomenon of weight and fat losses late in life. This review synthesizes data on aging-related changes in energy intake and energy expenditure and on the regulation of energy intake and expenditure. The ability of older adults to accurately regulate energy intake is impaired, with a number of possible explanations including delayed rate of absorption of macronutrients secondary to reductions in taste and smell acuity and numerous hormonal and metabolic mediators of energy regulation that change with aging. There are also changes in patterns of dietary intake and a reduction in the variety of foods consumed in old age that are thought to further reduce energy intake. Additionally, all components of energy expenditure decrease with aging, in particular energy expenditure for physical activity and basal metabolic rate, and the ability of energy expenditure to increase or decrease to attenuate energy imbalance during overeating or undereating also decreases. Combined, these changes result in an increased susceptibility to energy imbalance (both positive and negative) in old age that is associated with deteriorations in health. Practical interventions for prevention of weight and fat fluctuations in old age are anticipated here based on emerging knowledge of the role of such factors as dietary variety, taste, and palatability in late-life energy regulation.

A clinical trial of continuous subcutaneous insulin infusion versus multiple daily injections in older adults with type 2 diabetes

OBJECTIVE

To compare the efficacy and safety of continuous subcutaneous insulin infusion (CSII) and multiple daily injection (MDI) in older adults with insulin-treated type 2 diabetes and to assess treatment satisfaction and quality of life.

RESEARCH DESIGN AND METHODS

Adults (n = 107) > or =60 years of age (mean age 66 years) with insulin-treated type 2 diabetes (mean duration 16 years, BMI 32 kg/m(2), and HbA(1C) [A1C] 8.2%) were randomized to CSII (using insulin lispro) or MDI (using insulin lispro and insulin glargine) in a two-center, 12-month, prospective, randomized, controlled clinical trial. Efficacy was assessed with A1C, safety by frequency of hypoglycemia, and treatment satisfaction and quality of life with the Diabetes Quality of Life Clinical Trial Questionnaire and the 36-item short-form health survey, version 2.

RESULTS

Forty-eight CSII subjects (91%) and 50 MDI subjects (93%) completed the study. Mean A1C fell by 1.7 +/- 1.0% in the CSII group to 6.6% and by 1.6 +/- 1.2% in the MDI group to 6.4%. The difference in A1C between treatment groups was not statistically significant (P = 0.20). Eighty-one percent of CSII subjects and 90% of MDI subjects experienced at least one episode of minor (self-treated) hypoglycemia (P = 0.17), and three CSII and six MDI subjects experienced severe hypoglycemia (P = 0.49). Rates of severe hypoglycemia were similarly low in the two groups (CSII 0.08 and MDI 0.23 events per person-year, P = 0.61). Weight gain did not differ between groups (P = 0.70). Treatment satisfaction improved significantly with both CSII and MDI (P < 0.0001), and the difference between groups was not statistically significant (P = 0.58).

CONCLUSIONS

In older subjects with insulin-treated type 2 diabetes, both CSII and MDI achieved excellent glycemic control with good safety and patient satisfaction.