What patient-reported outcome measures may be suitable for research involving older adults with frailty? A scoping review.

INTRODUCTION: The need to develop and evaluate frailty-related interventions is increasingly important, and inclusion of patient-reported outcomes is vital. Patient-reported outcomes can be defined as measures of health, quality of life or functional status reported directly by patients with no clinician interpretation. Numerous validated questionnaires can thus be considered patient-reported outcome measures (PROMs). This review aimed to identify existing PROMs currently used in quantitative research that may be suitable for older people with frailty. METHOD: PubMed and Cochrane were searched up to 24/11/22. Inclusion criteria were quantitative studies, use of a PROM, and either measurement of frailty or inclusion of older adult participants. Criteria were created to distinguish PROMs from questionnaire-based clinical assessments. 197 papers were screened. PROMs were categorized according to the domain assessed, as derived from a published consensus 'Standard Set of Health Outcome Measures for Older People'. RESULTS: 88 studies were included. 112 unique PROMs were used 289 times, most frequently the SF-36 (n = 21), EQ-5D (n = 21) and Barthel Index (n = 14). The most frequently assessed outcome domains included Mood and Emotional Health and Activities of Daily Living, with fewer assessments of Participation in Decision-Making and Carer Burden. CONCLUSIONS: PROM usage in frailty research is highly heterogeneous. Frequently used PROMs omit important outcomes identified by older adults. Further research should evaluate the importance of specific outcomes and identify PROMs relevant to people at different stages of frailty. Consistent and appropriate PROM use in frailty research would facilitate more effective comparisons and meaningful evaluation of frailty interventions.

The evolving continuum of dysglycaemia: Non-diabetic hyperglycaemia in older adults.

Identifying non-diabetic hyperglycaemia (NDH) and intervening to halt the progression to type 2 diabetes has become an essential component of cardiovascular and cerebrovascular risk reduction. Diabetes prevention programs have been instigated to address the increasing prevalence of NDH and type 2 diabetes by targeting lifestyle modifications. Evidence suggests that the risk of progression from NDH to type 2 diabetes declines with age, and that a diagnosis of type 2 diabetes in older adults is not associated with the same risk of adverse consequences as it is in younger age groups. The current definition of NDH is not adjusted based on a person's age. Therefore, there is debate about the emphasis that should be placed upon a diagnosis of NDH in older adults. This article will explore the evidence and current clinical practice surrounding dysglycaemia through the spectrum of different age ranges, and the potential implications this has for older adults.

Type 2 diabetes mellitus in older people: a brief statement of key principles of modern day management including the assessment of frailty. A national collaborative stakeholder initiative.

Rates of population ageing are unprecedented and this, combined with the progressive urbanization of lifestyles, has led to a dramatic shift in the epidemiology of diabetes towards old age, particularly to those aged 60-79 years. Both ageing and diabetes are recognized as important risk factors for the development of functional decline and disability. In addition, diabetes is associated with a high economic, social and health burden. Traditional macrovascular and microvascular complications of diabetes appear to account for less than half of the diabetes-related disability observed in older people. Despite this, older adults are under-represented in clinical trials. Guidelines from organizations such as the National Institute for Health and Care Excellence (NICE), the European Association for the Study of Diabetes, and the American Diabetes Association acknowledge the need for individualized care, but the glycaemic targets that are suggested to constitute good control [HbA1c 53-59 mmol/mol (7-7.5%)] are too tight for frail older individuals. We present a framework for the assessment of older adults and guidelines for the management of this population according to their frailty status, with the intention of reducing complications and improving quality of life for these people.

Random non-fasting C-peptide: bringing robust assessment of endogenous insulin secretion to the clinic.

BACKGROUND: Measuring endogenous insulin secretion using C-peptide can assist diabetes management, but standard stimulation tests are impractical for clinical use. Random non-fasting C-peptide assessment would allow testing when a patient is seen in clinic. METHODS: We compared C-peptide at 90 min in the mixed meal tolerance test (sCP) with random non-fasting blood C-peptide (rCP) and random non-fasting urine C-peptide creatinine ratio (rUCPCR) in 41 participants with insulin-treated diabetes [median age 72 (interquartile range 68-78); diabetes duration 21 (14-31) years]. We assessed sensitivity and specificity for previously reported optimal mixed meal test thresholds for severe insulin deficiency (sCP < 200 pmol//l) and Type 1 diabetes/inability to withdraw insulin (< 600 pmol//l), and assessed the impact of concurrent glucose. RESULTS: rCP and sCP levels were similar (median 546 and 487 pmol//l, P = 0.92). rCP was highly correlated with sCP, r = 0.91, P < 0.0001, improving to r = 0.96 when excluding samples with concurrent glucose < 8 mmol//l. An rCP cut-off of 200 pmol//l gave 100% sensitivity and 93% specificity for detecting severe insulin deficiency, with area under the receiver operating characteristic curve of 0.99. rCP < 600 pmol//l gave 87% sensitivity and 83% specificity to detect sCP < 600 pmol//l. Specificity improved to 100% when excluding samples with concurrent glucose < 8 mmol//l. rUCPCR (0.52 nmol/mmol) was also well-correlated with sCP, r = 0.82, P < 0.0001. A rUCPCR cut-off of < 0.2 nmol/ mmol gave sensitivity and specificity of 83% and 93% to detect severe insulin deficiency, with area under the receiver operating characteristic curve of 0.98. CONCLUSIONS: Random non-fasting C-peptide measures are strongly correlated with mixed meal C-peptide, and have high sensitivity and specificity for identifying clinically relevant thresholds. These tests allow assessment of C-peptide at the point patients are seen for clinical care.

Urinary C-peptide creatinine ratio detects absolute insulin deficiency in Type 2 diabetes.

AIMS: To determine the prevalence and clinical characteristics of absolute insulin deficiency in long-standing Type 2 diabetes, using a strategy based on home urinary C-peptide creatinine ratio measurement. METHODS: We assessed the urinary C-peptide creatinine ratios, from urine samples taken at home 2 h after the largest meal of the day, in 191 insulin-treated subjects with Type 2 diabetes (diagnosis age ≥45 years, no insulin in the first year). If the initial urinary C-peptide creatinine ratio was ≤0.2 nmol/mmol (representing absolute insulin deficiency), the assessment was repeated. A standardized mixed-meal tolerance test with 90-min stimulated serum C-peptide measurement was performed in nine subjects with a urinary C-peptide creatinine ratio ≤ 0.2 nmol/mmol (and in nine controls with a urinary C-peptide creatinine ratio >0.2 nmol/mmol) to confirm absolute insulin deficiency. RESULTS: A total of 2.7% of participants had absolute insulin deficiency confirmed by a mixed-meal tolerance test. They were identified initially using urinary C-peptide creatinine ratio: 11/191 subjects (5.8%) had two consistent urinary C-peptide creatinine ratios ≤ 0.2 nmol/mmol; 9 of these 11 subjects completed a mixed-meal tolerance test and had a median stimulated serum C-peptide of 0.18 nmol/l. Five of these 9 had stimulated serum C-peptide <0.2 nmol/l and 9/9 subjects with urinary C-peptide creatinine ratio >0.2 had endogenous insulin secretion confirmed by the mixed-meal tolerance test. Compared with subjects with a urinary C-peptide creatinine ratio >0.2 nmol/mmol, those with confirmed absolute insulin deficiency had a shorter time to insulin treatment (median 2.5 vs. 6 years, P=0.005) and lower BMI (25.1 vs. 29.1 kg/m(2) , P=0.04). Two out of the five patients with absolute insulin deficiency were glutamic acid decarboxylase autoantibody-positive. CONCLUSIONS: Absolute insulin deficiency may occur in long-standing Type 2 diabetes, and cannot be reliably predicted by clinical features or autoantibodies. Absolute insulin deficiency in Type 2 diabetes may increase the risk of hypoglycaemia and ketoacidosis, as in Type 1 diabetes. Its recognition should help guide treatment, education and management. The urinary C-peptide creatinine ratio is a practical non-invasive method to aid detection of absolute insulin deficiency, with a urinary C-peptide creatinine ratio > 0.2 nmol/mmol being a reliable indicator of retained endogenous insulin secretion.

Urine C-peptide creatinine ratio is an alternative to stimulated serum C-peptide measurement in late-onset, insulin-treated diabetes.

AIMS: Serum C-peptide measurement can assist clinical management of diabetes, but practicalities of collection limit widespread use. Urine C-peptide creatinine ratio may be a non-invasive practical alternative. The stability of C-peptide in urine allows outpatient or community testing. We aimed to assess how urine C-peptide creatinine ratio compared with serum C-peptide measurement during a mixed-meal tolerance test in individuals with late-onset, insulin-treated diabetes. METHODS: We correlated the gold standard of a stimulated serum C-peptide in a mixed-meal tolerance test with fasting and stimulated (mixed-meal tolerance test, standard home meal and largest home meal) urine C-peptide creatinine ratio in 51 subjects with insulin-treated diabetes (diagnosis after age 30 years, median age 66 years, median age at diagnosis 54, 42 with Type 2 diabetes, estimated glomerular filtration rate > 60 ml min(-1) 1.73 m(-2) ). RESULTS: Ninety-minute mixed-meal tolerance test serum C-peptide is correlated with mixed-meal tolerance test-stimulated urine C-peptide creatinine ratio (r = 0.82), urine C-peptide creatinine ratio after a standard breakfast at home (r = 0.73) and urine C-peptide creatinine ratio after largest home meal (r = 0.71). A stimulated (largest home meal) urine C-peptide creatinine ratio cut-off of 0.3 nmol/mmol had a 100% sensitivity and 96% specificity (area under receiver operating characteristic curve = 0.99) in identifying subjects without clinically significant endogenous insulin secretion (mixed-meal tolerance test-stimulated C-peptide < 0.2 nmol/l). In detecting a proposed serum C-peptide threshold for insulin requirement (stimulated serum C-peptide < 0.6 nmol/l), a stimulated (largest home meal) urine C-peptide creatinine ratio cut-off of 0.6 nmol/mmol had a sensitivity and specificity of 92%. CONCLUSION: In patients with insulin-treated diabetes diagnosed after age 30 years, urine C-peptide creatinine ratio is well correlated with serum C-peptide and may provide a practical alternative measure to detect insulin deficiency for use in routine clinical practice.