Abstract
Introduction: Forced Vital Capacity (FVC) gradually decrease in Ataxia telangiectasia (A-T).
Aim: to determine the effect of FVC decline on life span in A-T.
Methods: Clinical data and yearly best spirometry maneuvers (195 visits) were collected retrospectively during 6yrs, from 37 A-T patients (age 4-21y) attending the A-T national clinic in Israel. 11 patients were walking (ambulated); 26 were confined to wheelchair (Wch) from whom 7 patients died. Spirometry included tidal-volume (TV), FVC and mid-flows (FEF25-75) measurements. Findings were related to recurrent respiratory infections (rRI)
Results: Ambulant patients initial and last FVC were 67+8 and 51+17 %predicted (%P) with a TV/FVC ratio of 23+4% and 26+7% respectively (lower than healthy). Deterioration in FVC accelerated from 2yrs after being confined to the Wch. In deceased patients initial FVC was 31+7%p and 19+6%p prior to death (P=0.0125) while TV/FVC ratio increased from 39+9% 5yrs and to 73+11% 2yrs prior to death (p=0.0001). Ambulant patients without rRI (n=6) had FEF25-75 of 121+16%p indicating restrictive pattern. Once rRI occurred (n=31) FEF25-75 values decreased gradually to 69+27%p at the last measure near death (p=0.0001). FEF25–75/FVC ratio was 2.54+0.70 above normal in all patients until 2yrs prior to death when values increased significantly reaching 4.17+2.08 ratios.
Conclusion: Findings indicate that 5yrs prior to death TV/FVC ratios elevate to levels implying respiratory distress. Moderately reduced FEF25-75 may indicate severe airway obstruction. TV/FVC and FEF25-75/FVC ratios increase abruptly 2yrs prior to death. Treating physicians should be aware of these red flags.
- © 2014 ERS
