2004 OPEN FORUM Abstracts
NEURORESPIRATORY SYNDROME IN COPD PATIENTS
Pavel N. Barlamov,
MD, PhD1, Vladimir V. Shchokotov, MD, PhD1,Anna
B. Edlebeck, MD, PhD1Perm
State Medical Academy, Perm, Russia
Background: Chronic obstructive pulmonary disease (COPD) is an important public health problem worldwide, and is currently one of the leading causes of morbidity and mortality in both US and Russia. Many COPD patients present with concurrent breathing disorders, e g sleep apnea or hyperventilation syndrome (HVS). HVS is a widely known autonomic nervous system (ANS) dysfunction which is frequently associated with emotional disturbances, and can have a potential impact on the course of COPD and quality of life as well. However, there is no sufficient information regarding HVS in COPD patients.
Methods: 60 patients with COPD (47 males, 13 females, age 36-69, mean age 52.7 yrs) in steady state were included in the study. 12 (20%) of the patients had mild COPD, 22 (36.7%) had moderate, and 26 (43.3%) – severe disease (ETS criteria, 1995). The majority of the patients - 49 (81.7%) had the smoking history (1.25 to 60 pack-years). 17 healthy subjects with matching age and sex were included in the control group. The complex investigation included the use of the special questionnaires and algorithms for ANS dysfunction evaluation, spirometry with bronchodilator (Berodual) test and hyperventilation test, capnography with hyperventilation provocation test (HVPT), heart rhythm variability (HRV) study with tests on ANS function (tonicity, reactivity, support), Minnesota Multiple Personality Inventory (MMPI) and Spilberger anxiety tests.
Purpose: To evaluate the ANS dysfunction, presence of HVS, and emotional disturbances in COPD patients.
Results: Symptoms of autonomic dysfunction were present in 54 (90%) patients. The HRV study showed an activation of sympathetic function at rest, inverted autonomic reactivity and deficient support (p<0.05 when compared to control subjects). 41(68.3%) of the patients had the chronic HVS (75% of the patients with mild COPD, 73.3% with moderate, and 57,7% with advanced COPD). Patients with mild and moderate COPD had prominent hypocapnia during HVPT recovery period (PaCO2 4,49± 0,24 vol%, p<0,001 and 4,4± 0,23 vol%, p<0,01). Personal and situational anxiety traits were more prominent in the group of patients with HVS (46,72± 1,14, p<0.01, 44,38± 1,64, p<0.05, respectively), and so were the MMPI profile changes with peaks on axis 3, 4, 6, 8, characterizing presence of anxiety, depression and somatization. Conclusion: HVS as a part of the autonomic dysregulaton is a very common breathing disorder in the patients with COPD. On this matter, we suggest a definition of the neurorespiratory syndrome to combine the abovementioned disturbances. It is recommended that this syndrome should be taken into consideration at the time of discussing the options of treatment.