Utility of NT-proBNP as a rule-out test for left ventricular dysfunction in very old people with limiting dyspnoea: the Newcastle 85+ Study

Diagnostic approach to chronic dyspnoea in adults

Chronic dyspnoea, or breathlessness for more than four weeks duration, is a common symptom in adults presenting to primary and tertiary care. It often presents a diagnostic challenge due to the wide spectrum of underlying disease, which is multifactorial in approximately one third of cases. Challenges in diagnosis include an often non-diagnostic clinical assessment, difficulty in selecting the most appropriate investigations and correct speciality referral for further diagnostic assessment. In patients presenting with chronic dyspnoea, history and physical examination are often non-specific with key findings more useful as negative predictive factors. There is a broad range of simple to specialised investigations that may be utilised in the diagnostic workup. Several diagnostic algorithms incorporating different tiers of investigations have been tested in studies of chronic dyspnoea patients but there is currently very limited data that test a diagnostic algorithm against standard clinical care. In this review we propose a diagnostic pathway with primary, secondary and tertiary level investigations for patients with chronic dyspnoea. This pathway is based on the combination of previously tested diagnostic algorithms in the literature, to assist clinicians in their diagnostic workup of chronic dyspnoea patients. Further research is needed to further evaluate diagnostic algorithms in this setting and to test this diagnostic pathway in clinical practice.

ADMA and NT pro-BNP are associated with overall mortality in elderly

BACKGROUND

Increased asymmetrical dimethylarginine (ADMA) and NT pro-BNP concentrations have been associated with mortality in patients with cardiovascular (CV) disease and the general population. The use of these prognostic markers in an older population is not established yet. The aim of the present study was to investigate the prognostic value of age, sex, BMI, co-medication and CV laboratory risk markers in geriatric care patients.

MATERIALS AND METHODS

In this prospective observational single-centre cohort study data of long-term geriatric care patients were collected. Blood samples were collected between 14.09.2009 and 16.12.2009, and mortality was recorded up to 90 months. ADMA, its symmetric isomer SDMA, L-arginine, NT pro-BNP and CRP were determined at study entry. Simple associations of risk factors for survival period were explored by Spearman correlation coefficient. Significant univariate predictors for survival period were used in the Cox proportional hazard model.

RESULTS

A total of 481 patients were screened, and data from 449 patients were analysed. A total of 381 patients died during the observation period. Full data sets from 344 patients were used for Cox regression analysis. Male sex, older age, lower BMI, use of neuroleptic medicine, peripheral artery disease, and elevated plasma concentrations of ADMA, NT pro-BNP, and CRP were significant predictors of mortality.

CONCLUSION

The concentration of ADMA and NT pro-BNP may be used as an early risk marker for overall mortality in geriatric care. Neuroleptic medicine is associated with increased mortality in this population.

Diagnostic rules and algorithms for the diagnosis of non-acute heart failure in patients 80 years of age and older: a diagnostic accuracy and validation study

OBJECTIVES

Different diagnostic algorithms for non-acute heart failure (HF) exist. Our aim was to compare the ability of these algorithms to identify HF in symptomatic patients aged 80 years and older and identify those patients at highest risk for mortality.

DESIGN

Diagnostic accuracy and validation study.

SETTING

General practice, Belgium.

PARTICIPANTS

365 patients with HF symptoms aged 80 years and older (BELFRAIL cohort). Participants underwent a full clinical assessment, including a detailed echocardiographic examination at home.

OUTCOME MEASURES

The diagnostic accuracy of 4 different algorithms was compared using an intention-to-diagnose analysis. The European Society of Cardiology (ESC) definition of HF was used as the reference standard for HF diagnosis. Kaplan-Meier curves for 5-year all-cause mortality were plotted and HRs and corresponding 95% CIs were calculated to compare the mortality risk predicting abilities of the different algorithms. Net reclassification improvement (NRI) was calculated.

RESULTS

The prevalence of HF was 20% (n=74). The 2012 ESC algorithm yielded the highest sensitivity (92%, 95% CI 83% to 97%) as well as the highest referral rate (71%, n=259), whereas the Oudejans algorithm yielded the highest specificity (73%, 95% CI 68% to 78%) and the lowest referral rate (36%, n=133). These differences could be ascribed to differences in N-terminal probrain natriuretic peptide cut-off values (125 vs 400 pg/mL). The Kelder and Oudejans algorithms exhibited NRIs of 12% (95% CI 0.7% to 22%, p=0.04) and 22% (95% CI 9% to 32%, p<0.001), respectively, compared with the ESC algorithm. All algorithms detected patients at high risk for mortality (HR 1.9, 95% CI 1.4 to 2.5; Kelder) to 2.3 (95% CI 1.7 to 3.1; Oudejans). No significant differences were observed among the algorithms with respect to mortality risk predicting abilities.

CONCLUSIONS

Choosing a diagnostic algorithm for non-acute HF in elderly patients represents a trade-off between sensitivity and specificity, mainly depending on differences between cut-off values for natriuretic peptides.

Association between cystatin C and heart failure with preserved ejection fraction in elderly Chinese patients

BACKGROUND

Approximately 50 % of patients with heart failure have a preserved ejection fraction (HFpEF). Cystatin C has been reported to be associated with cardiovascular events. This study was carried out to investigate whether cystatin C is associated with cardiac function and cardiac diastolic properties in elderly Chinese HFpEF patients.

MATERIAL AND METHODS

A cross-sectional study of 381 elderly Chinese HFpEF patients (81 women, average age 82 ± 6 years) was conducted. Serum concentrations of cystatin C and the New York Heart Association (NYHA) classification were assessed and early (E) to late (A) transmitral flow velocity ratios (E/A ratio) were measured to assess cardiac diastolic properties.

RESULTS

Cystatin C levels, N‑terminal pro brain natriuretic peptide (NT-proBNP) levels and age were significantly correlated to the NYHA class (r = 0.605 P < 0.001, r = 0.333 P < 0.001 and r = 0.254 P < 0.001, respectively). Cystatin C levels, age and body mass index (BMI) were negatively correlated to the E/A ratio (r = -0.224 P = 0.005, r = -0.258 P = 0.001 and r = -0.258 P = 0.003, respectively). The patients with cystatin C concentrations below 1.3 mg/l had a higher E/A ratio compared to those with cystatin C concentrations higher than 1.3 mg/l. Cystatin C was also significantly associated with both the NYHA classification and the E/A ratio even after adjustment for the creatinine clearance rate (CCr).

CONCLUSION

Both cystatin C and NT-proBNP were found to be correlated to the NYHA classification. Independent of renal function, higher serum concentrations of cystatin C were associated with a worse NYHA classification and abnormal cardiac diastolic properties in elderly Chinese HFpEF patients.