ABSTRACT
BACKGROUND: Patients with chronic heart failure (CHF) commonly fatigue easily due to low peak oxygen uptake (peak VO(2)), an important index of exercise capacity. Maximum phonation time (MPT) is widely used to evaluate maximum vocal capabilities because it is non-invasive, quick, and inexpensive. AIM: The aim of this study was to determine the relation between MPT and exercise capacity, and MPT required to attain an exercise capacity of ≥5 metabolic equivalents (METs) in CHF outpatients. DESIGN: Cross-sectional study. SETTING: Outpatient cardiac rehabilitation unit. POPULATION: We enrolled 111 CHF outpatients (mean age 54.2±10.1 years). METHODS: Peak VO(2) was assessed during cardiopulmonary exercise testing (CPX) as the index of exercise capacity. After CPX, we divided the patients into two groups according to exercise capacity: ≥5 METs group (N.=68) and <5 METs group (N.=43). Measurements of MPT were taken in the seated position. All patients were asked to produce a sustained vowel /a:/ for as long as possible and were verbally encouraged during respiratory effort. RESULTS: After adjustment for patient clinical characteristics, MPT in the CHF patients was found to be significantly higher in the ≥5 METs group than in the <5 METs group (22.1±8.4 vs. 17.0±11.6 s, F=13.5, P<0.001). Receiver-operating characteristic curve analysis of exercise capacity of ≥5 METs extracted a cutoff value for MPT of 18.27 s, with a sensitivity of 0.76, 1-specificity of 0.33, and AUC value of 0.81 (95% CI: 0.70-0.87, P<0.001). CONCLUSION: There were differences in MPT in relation to an exercise capacity threshold of ≥5 METs in CHF outpatients. A MPT of 18.27 sec may be the best cutoff value to identify people with or without exercise capacity of ≥5 METs. CLINICAL REHABILITATION IMPACT: Measurement of MPT may be a useful method for estimating exercise capacity in CHF outpatients.
Subject(s)
Exercise Tolerance/physiology , Heart Failure/physiopathology , Oxygen Consumption/physiology , Phonation/physiology , Chronic Disease , Cross-Sectional Studies , Exercise Test , Female , Heart Failure/rehabilitation , Humans , Japan , Male , Middle Aged , ROC CurveABSTRACT
In Hegura Island, Japan, we have recently found female divers who suffer from a disorder called 'Chiyamai'. From interviews, questionnaires and temporarily proposed diagnostic criteria for Chiyamai, nine cases from 44 female divers interviewed, were diagnosed as having Chiyamai. Clinically, Chiyamai is characterized by a panic-like attack. Ten symptoms were observed during a panic-like attack, compared with 13 symptoms in a panic attack described in the DSM-IV. The average age at onset was 30 years and the average duration of illness was approximately 26 years. Several cases were so severe that the patients were unable to continue diving. Additionally, we report a typical case of Chiyamai, and discussed the similarities and differences between Chiyamai and anxiety disorders in the DSM-IV. We suggest that Chiyamai is a panic-like disorder specific to female divers from Hegura Island and that it is a result of heavy diving.
