Association between HbA1c and the development of cystic fibrosis-related diabetes

AIMS

To examine HbA_1c as a predictor of risk for future development of cystic fibrosis-related diabetes and to assess the association with the development of retinopathy in people with cystic fibrosis-related diabetes.

METHODS

A 7-year retrospective longitudinal study was conducted in 50 adults with cystic fibrosis, comparing oral glucose tolerance test results with HbA_1c values in predicting the development of cystic fibrosis-related diabetes. Retinal screening data were also compared with HbA_1c measurements to assess microvascular outcome.

RESULTS

An HbA_1c value ≥37 mmol/mol (5.5%; hazard ratio 3.49, CI 1.5-8.1) was significantly associated with the development of dysglycaemia, as defined by the oral glucose tolerance test over a 7-year period. Severity of diabetic retinopathy was associated with a higher HbA_1c and longer duration of cystic fibrosis-related diabetes.

CONCLUSION

There is a link between HbA_1c level and the future development of dysglycaemia in cystic fibrosis based on oral glucose tolerance test, as well as microvascular outcomes. Although current guidance does not advocate the use of HbA_1c as a diagnostic tool in cystic fibrosis-related diabetes, it may be of clinical use in determining individuals at risk of future development of cystic fibrosis-related diabetes.

Telemedicine is the way forward for the management of cystic fibrosis - the case in favour

Despite rapid changes in Information and Communication Technology, outpatient chronic disease management has changed very little in decades. However, the introduction of Telemedicine defined here as the use of remote patient-centred clinical services including the use of video and audio connections, telemonitoring and mobile applications provides us with an ideal opportunity to revolutionise care. Its appeal in cystic fibrosis (CF) care is clear offering better access to services, the opportunity of earlier intervention and improved monitoring and self management through virtual clinics and the use of real-time applications for adherence monitoring. It has the potential to reduce costs and has been shown to be effective in other chronic disease conditions. There is a lack of good quality data in CF and studies are needed to provide supportive evidence. Nonetheless, it would seem that telemedicine is the future of CF care.

Lifestyle treatments in cystic fibrosis: The NHS should pay

With the NHS under increasing financial pressure and healthcare costs soaring year on year, it is perhaps not surprising that assessment agencies focus on cost-effectiveness analysis when assessing new therapies. Such an approach does not however, always take sufficient account of treatment burden, lifestyle and patient choice and therefore new equally effective but perhaps "easier to take" formulations and faster delivery systems for current therapies do not always take precedence in current treatment guidelines. In arguing that the NHS should pay for so-called lifestyle treatments in cystic fibrosis the counterintuitive nature of some of the current decision making is discussed and a more holistic approach to improve NHS efficiency is presented.

Hyperpharmacotherapy in ageing cystic fibrosis patients: The first report of an atypical hip fracture

Cystic fibrosis (CF) is a common autosomal recessive disorder in Caucasian populations with respiratory, gastrointestinal and endocrine manifestations. Thanks to recent advances in medical therapies and infection control, life expectancy of a patient with CF has significantly increased from less than 5 years in the mid-1900s to almost 50 years nowadays. However, as CF patients are living longer, multimorbidity and Hyperpharmacotherapy are becoming more common. This case illustrates a cascade of problems that ensued from medication side-effects, highlighting the increasing challenge of managing an ageing CF population.

Do patient-reported outcomes have a role in the management of patients with cystic fibrosis?

BACKGROUND

Health-related quality of life (HRQoL) is a rapidly growing area of expertise and the most commonly used patient-reported outcome (PRO). The impact of cystic fibrosis (CF) on HRQoL is liable to be great, making CF patients ideal candidates for the application of HRQoL instruments. The aims of this study were to assess the affect of CF on HRQoL, to ascertain the reliability and validity of the United Kingdom Sickness Impact Profile (UKSIP) and the Cystic Fibrosis Quality of Life Questionnaire (CFQoL) in the adult CF population, and to examine their role in the management of patients.

METHODS

Seventy participants were recruited from the All Wales Adult Cystic Fibrosis Centre at Llandough Hospital, UK. There were two stages to the study: self-report of the UKSIP and CFQoL; and completion of the same two questionnaires 7-10 days later.

RESULTS

The areas of HRQoL most impaired by CF were employment and concerns regarding the future. The UKSIP and CFQoL showed high internal consistency (rα = 0.89-0.93) and test-retest reliability (r(s) = 0.57-0.94, p < 0.005) in the CF population. Validity was variable with the UKSIP showing discrimination across socio-demographic factors, whilst the CFQoL showed increased sensitivity to clinical variables. Many parameters influenced patient-reported HRQoL, with the greatest correlations seen with the Borg score (p < 0.005). The use of a HRQoL instrument in CF annual reviews is recommended to provide holistic patient care. The results of this study underpin the value of HRQoL as a patient-reported outcome measure in the management of adult CF.

Contrasting effects of allergen challenge on airway responsiveness to cysteinyl leukotriene D(4) and methacholine in mild asthma

BACKGROUND

Cysteinyl leukotrienes (cysteinyl-LTs) have been implicated in the pathogenesis of allergen induced airway responses. Airway responsiveness (AR) to inhaled cysteinyl-LTs is dramatically increased following allergen challenge in animal studies. The effect in man has not been evaluated.

METHODS

Ten mild steroid-naïve asthmatic subjects with an isolated early asthmatic response (EAR) and 21 with an additional late asthmatic response (LAR) took part in a randomised controlled crossover study to assess AR to inhaled methacholine (MCh) and cysteinyl-LT D(4) (LTD(4)) 22 and 24 hours, respectively, after allergen challenge. Eight subjects had two further LTD(4) challenges separated by a 2 week washout period to assess the reproducibility of inhaled LTD(4) challenge.

RESULTS

In subjects with an isolated EAR, non-significant mean (SE) increases in AR of 0.4 (0.4) doubling doses (DD) for MCh and 0.4 (0.5) DD for LTD(4) followed allergen challenge compared with control. A significant correlation between AR to MCh and LTD(4) followed both control (r=0.91, 95% CI 0.67 to 0.98; p=0.0002) and allergen challenge (r=0.79, 95% CI 0.32 to 0.95; p=0.0063). In subjects with an additional LAR there was a significant increase in AR to MCh (1.2 (0.3) DD, p=0.0005) following allergen challenge but no overall effect on AR to LTD(4) (0.69 (0.4) DD, p=0.11). A significant correlation between AR to MCh and LTD(4) was again observed (r=0.70; 95% CI 0.38 to 0.87; p=0.0004) following control, although it was reduced following allergen challenge (r=0.48; 95% CI 0.063 to 0.76; p=0.027). LTD(4) challenge was highly reproducible with a mean difference of 0.2 (0.3) DD between challenges.

CONCLUSIONS

Allergen challenge significantly increases AR to inhaled MCh but not to LTD(4) in subjects with LAR. The lack of a comparable increase in AR to LTD(4) is surprising. Endogenous cysteinyl-LTs are produced in abundance following allergen challenge and may enhance AR to MCh or induce a degree of tachyphylaxis to LTD(4).

Dose-related effects of formoterol on airway responsiveness to adenosine 5'-monophosphate and histamine

Inhaled short-acting beta2-agonists provide greater protection against airway responsiveness (AR) to the mast-cell stimulus, adenosine 5'-monophosphate (AMP), than to histamine, a direct spasmogen. Both terbutaline and albuterol exhibit this mast-cell stabilizing property in a dose-dependent manner. A single dose of the long-acting beta2-agonist formoterol has also been reported to have a mast cell-stabilizing effect, whereas salmeterol has not. To explore the dose-related actions of the long-acting beta2-agonist formoterol on AR, the authors compared the acute effects of three doses of formoterol and terbutaline on AR to AMP and histamine. In a double-blind, randomized, placebo-controlled, cross-over study, 25 mild, steroid naive, asthmatic subjects attended on 10 occasions. At each visit, subjects inhaled either a single dose of terbutaline (500 microg), formoterol (6, 12 or 24 microg) or a matched placebo, administered via Turbuhaler, 30 min prior to challenge with both AMP and histamine. Each dose of beta2-agonist reduced AR to AMP and histamine. The bronchoprotective effects of formoterol (6 microg) and terbutaline (500 microg) were similar in magnitude in reducing AR to histamine (mean +/- SD: 3.6 +/- 0.3 and 3.1 +/- 0.3 doubling doses (DD)) and AR to AMP (3.5 +/- 0.5 and 3.3 +/- 0.4 DD, respectively). Overall, formoterol reduced AR to both spasmogens in a dose-dependent manner. In addition, formoterol (12 and 24 microg) provided a significantly greater protective effect against AMP than against histamine challenge. It decreased AR by 5.7 +/- 0.6 and 6.3 +/- 0.7 DD against AMP and 4.3 +/- 0.4 and 4.8 +/- 0.43 DD against histamine, respectively. The results of this study indirectly demonstrated an in vivo dose-dependent mast-cell stabilizing effect of formoterol, in addition to functional antagonism on airway smooth muscle. This property of beta2-agonists may have clinical benefits in asthma management.