Six-minute walking distance and desaturation-distance ratio in allogeneic stem cell transplantation.

BACKGROUND: Most patients with haematological malignancies who undergo allogeneic haematopoietic stem cell transplant (HSCT) receive chemotherapy before the transplant to control the disease. Certain chemotherapy drugs can cause lung toxicity. Conversely, in patients with chronic respiratory conditions, the 6-min walking test (6MWT) and the desaturation-distance ratio (DDR) have demonstrated prognostic significance. Our objective was to determine whether the 6MWD and DDR, assessed prior to HSCT, have a prognostic impact on survival at 24 months post-HSCT. METHODS: A prospective experimental study was conducted in consecutive patients referred for allogeneic HSCT at Hospital Clinic, Barcelona, Spain. A complete functional respiratory study, including the 6MWT and DDR, was conducted prior to admission. The area under the curve (AUC) and cut-off points were calculated. Data on patients' characteristics, HSCT details, main events, with a focus on lung complications, and survival at 24 months were analysed. RESULTS: One hundred and seventy-five patients (39% women) with mean age of 48 ± 13 years old were included. Before HSCT, forced vital capacity and forced expiratory volume in the first second were 96% ± 13% predicted and 92% ± 14% predicted, respectively; corrected diffusing capacity for carbon monoxide 79% ± 15% predicted; 6MWD was 568 ± 83 m and DDR of .27 (.20-.41). The cut-off points for 6MWD and DDR were 566 m, [.58 95% CI (.51-.64)], p = .024 and .306, [.63 95% CI (.55-.70)], p = .0005, respectively. The survival rate at 24 months was 55%. CONCLUSION: Our results showed that individuals who exhibit a 6MWD shorter than 566 ms or a decline in DDR beyond .306 experienced reduced survival rates at 24 months after HSCT.

Does arterial oxygenation during exercise add prognostic value in pulmonary arterial hypertension?

BACKGROUND: The 6-min walking distance (6MWD) is often used to assess prognosis in pulmonary arterial hypertension (PAH) patients. Whether or not changes in arterial oxygen saturation (SpO2) during exercise add prognostic value to the 6MWD in these patients is unclear. The objective of this study was to investigate if SpO2 changes during exercise adds prognostic value to the 6MWD in PAH patients. METHODS: Ambispective study that includes 137 patients with PAH: 38 idiopathic/heritable (i/h PAH), 42 with connective tissue disease (CTD-PAH), 34 with porto-pulmonary hypertension (PoPH), 21 with HIV-associated PAH and 2 with pulmonary venous occlusive disease (PVOD). Patients were characterized and, treated according to international recommendations, and were followed-up for 5 years. To integrate SpO2 changes during exercise, we calculated the desaturation distance ratio (DDR) either in its original form (from a maximal theoretical value of 100%) or the actual resting SpO2 value of the patient (new DDR) as well as the distance saturation product (DSP). RESULTS: (1) during follow-up, 40 patients died (29.2%); (2) results confirmed the prognostic value of the 6MWD (AUC 0.913 [IQR 0.868-0.958]; p < 0.0001), original DDR (AUC 0.923 [0.881-0.966]; p < 0.001), New DDR (AUC 0.917 [0.872-0.961], p < 0.001), and DSP (AUC 0.914 [0.869-0.959], p < 0.001); and, (3) neither the original or new DDR or DSP added significant prognostic value to 6MWD in these patients. CONCLUSIONS: Consideration of three different composite indices of arterial oxygenation changes during exercise does not add prognostic value to that of the 6MWD in patients with PAH.

[Spanish Society of Pulmonology and Thoracic Surgery (SEPAR) Consensus for post-COVID-19 Clinical Follow-up]. / Documento de consenso de la Sociedad Española de Neumología y Cirugía Torácica (SEPAR) para el seguimiento clínico post-COVID-19.

SARS-CoV-2 infection can cause a range of respiratory sequelae, especially in patients who have had severe Covid-19 pneumonia. Given the high number of patients who have developed this infection over a short period of time, numerous post-Covid-19 follow-up visits are being carried out, but no clinical follow-up protocol has been established to advise on the complementary tests to be performed and the frequency of these procedures. This consensus document was drawn up by professionals from different areas of the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR) in order to assist the clinician in identifying possible respiratory complications that may occur during the months following the acute disease, and to protocolize their follow-up and additional tests to be performed. It recommends examinations and interventions to be carried out at various stages in the post-Covid-19 period, and details the specific objectives of these procedures. Primarily, we aim to ensure that patients receive timely clinical follow-up, following a pre-established schedule that takes into account the severity of the disease and the likelihood of long-term sequelae. Another objective is to avoid overloading the health system by eschewing examinations and/or consultations that are, in many cases, unnecessary. Finally, we define criteria for referring patients with specific established sequelae (interstitial lung disease, pulmonary vascular disease, bronchiectasis) to the corresponding specialized units.

A Simple Score for Future Risk Prediction in Patients with Controlled Asthma Who Undergo a Guidelines-Based Step-Down Strategy.

BACKGROUND: The minimum controlling dose of treatment must be established in patients with asthma, but the outcome of step-down is unpredictable. OBJECTIVE: To identify factors associated with risk of control loss when stepping down asthma treatment and to develop a score to predict this risk. METHODS: A prospective, multicenter study including adults with well-controlled asthma was performed. Treatment was stepped up or stepped down over a 12-month period to maintain asthma control. We determined associations between clinical and functional variables and step-down failure. Finally, we derived a score to predict loss of control in 1 cohort and validated it in an independent cohort. RESULTS: The derivation cohort consisted of 228 patients; 218 completed at least 1 step-down episode and a total of 495 step-down episodes were evaluated. A medical-record documented postbronchodilator spirometry result of <70% forced expiratory volume in 1 second (FEV1)/forced vital capacity (odds ratio [OR] = 2.08; 95% confidence interval [CI]: 1.26-3.43), current FEV1 < 80% (OR = 1.80; 95% CI: 1.03-3.14), ≥1 severe exacerbation in the previous 12 months (OR = 2.43; 95% CI: 1.48-4.01), and Asthma Control Test score < 25 (OR = 2.30; 95% CI: 1.35-3.92) were independently associated with failure. The score showed an area under the curve of 0.690 (95% CI: 0.633-0.747; P < .05) in the derivation cohort and 0.76 (95% CI: 0.643-0.882; P < .001) in a validation cohort of 114 patients. A score <4.5 implies a low risk of failure (<20%), whereas a score >8 implies a high risk (>40%). CONCLUSION: This score can facilitate the prediction of step-down failure before medication taper in patients with well-controlled asthma.