Reference values for spirometry in elderly individuals: a cross-sectional study of different reference equations

Background: Spirometry is the single most important test for the evaluation of respiratory function. The results are interpreted by comparing measured data with predicted values previously obtained from a reference population. Reference equations for spirometry have been discussed previously. The aim of this study was to compare reference values based on National Health and Nutrition Assessment Survey (NHANES III), European Community of Steel and Coal (ECSC), and Global Lung Initiative (GLI) equations in an elderly sample population. Methods: Subjects from the Geriatric Study on Health Effects of Air Quality in elder care centres who met the inclusion criteria were enrolled. Spirometry was performed according to international guidelines. The forced vital capacity, forced expiratory volume in 1 s, and FEV1/FVC ratio were reported as percentages of the predicted value, and the lower limit of normality was calculated. Results: Out of 260 elderly patients, 69.6% were women; the mean age was 83.0 ± 6.46 years with an age range of 65– 95 years. The lowest %FVC and %FEV1 values were obtained using the GLI reference equations. However, when NHANES III equations were used, the FEV1/FVC ratio was higher than ratios obtained from GLI and ECSC equations. The prevalence of airway obstruction was highest using ECSC equations, while GLI equations demonstrated more restrictive defects. Conclusions: The present study showed meaningful differences in the reference values, and consequently, in the results obtained using NHANES III, ECSC,  and GLI reference equations. The spirometry interpretation was also influenced by the reference equations used.

The impact of indoor air quality on respiratory health of older people living in nursing homes: spirometric and exhaled breath condensate assessments

In the Portuguese Geriatric Study of the Health Effects of Indoor Air Quality in Senior Nursing Homes, we aimed to evaluate the impact of indoor air contaminants on the respiratory symptoms and biomarkers in a sample of elderly living in nursing homes. A total of 269 elderly answered a health questionnaire, performed a spirometry and 150 out of these collected an exhaled breath condensate sample for pH and nitrites analysis. The study included the evaluation of indoor chemical and microbiological contaminants. The median age of the participants was 84 (78-87) years and 70.6% were women. The spirometric data indicated the presence of airway obstruction in 14.5% of the sample. Median concentrations of air pollutants did not exceed the existing standards, although increased peak values were observed. In the multivariable analysis, each increment of 100 µg/m³ of total volatile organic compounds was associated with the odds of respiratory infection in the previous three months ( OR̂ =1.05; 95% CI: 1.00-1.09). PM_2.5 concentrations were inversely associated with pH values ( β̂ = -0.04, 95%: -0.06 to -0.01, for each increment of 10 µg/m³). Additionally, a direct and an inverse association were found between total bacteria and FEV₁/FVC and FVC, respectively.

Reference values for spirometry in elderly individuals: a cross-sectional study of different reference equations

Background

Spirometry is the single most important test for the evaluation of respiratory function. The results are interpreted by comparing measured data with predicted values previously obtained from a reference population. Reference equations for spirometry have been discussed previously. The aim of this study was to compare reference values based on National Health and Nutrition Assessment Survey (NHANES III), European Community of Steel and Coal (ECSC), and Global Lung Initiative (GLI) equations in an elderly sample population.

Methods

Subjects from the Geriatric Study on Health Effects of Air Quality in elder care centres who met the inclusion criteria were enrolled. Spirometry was performed according to international guidelines. The forced vital capacity, forced expiratory volume in 1 s, and FEV₁/FVC ratio were reported as percentages of the predicted value, and the lower limit of normality was calculated.

Results

Out of 260 elderly patients, 69.6% were women; the mean age was 83.0 ± 6.46 years with an age range of 65–95 years. The lowest %FVC and %FEV₁ values were obtained using the GLI reference equations. However, when NHANES III equations were used, the FEV₁/FVC ratio was higher than ratios obtained from GLI and ECSC equations. The prevalence of airway obstruction was highest using ECSC equations, while GLI equations demonstrated more restrictive defects.

Conclusions

The present study showed meaningful differences in the reference values, and consequently, in the results obtained using NHANES III, ECSC, and GLI reference equations. The spirometry interpretation was also influenced by the reference equations used.

Hyptis pectinata: redox protection and orofacial antinociception

Hyptis pectinata L. Poit, known as 'sambacaitá', is used in Brazil to treat inflammatory and painful disorders. In this study, the antioxidant and orofacial antinociceptive properties of the aqueous extract of H. pectinata leaves (AEPH) were assessed using in vitro and in vivo models. Thus, AEPH reduced the 2,2-diphenyl-1-picrylhydrazyl radical up to 72.10% with an EC₅₀ of 14.56 µg/ml. It also inhibited 40.80% of the lipoperoxidation induced by 2'-azobis (2-amidinopropane) dihydrochloride in the thiobarbituric acid-reactive substances assay. The orofacial antinociceptive activity was evaluated in mice pre-treated with AEPH (100, 200 and 400 mg/kg, p.o.) and morphine (5 mg/kg, i.p.), which received afterwards formalin- (20 µl, 2% solution, s.c.), glutamate- (40 µl, 25 mM, s.c.) and capsaicin- (20 µl, 2.5 µg, s.c.) to induce orofacial nociception. AEPH at all doses reduced (p < 0.001) the nociceptive response in the first (43-62%) and second (47-80%) phases of the formalin test. Besides, the effect of AEPH (400 mg/kg) was not changed in the presence of naloxone (1.5 mg/kg, i.p.), an opioid antagonist. AEPH significantly inhibited mice face rubbing for capsaicin (23-69%, p < 0.05) and glutamate (48-77%, p < 0.001) at all doses. The findings suggested the AEPH has peripheral and central antinociceptive activities, which are not related to opioid receptors.

Lippia sidoides and Myracrodruon urundeuva gel prevents alveolar bone resorption in experimental periodontitis in rats

In Brazilian folk medicine, Lippia sidoides (Ls) and Myracrodruon urundeuva (Mu) have gained popularity and reputation as effective antimicrobial and anti-inflammatory agents. This work aimed to evaluate the effect of topical herbal gel from Ls 0.5% (v/w) and Mu 5% (w/w) in experimental periodontal disease (EPD) in rats. Wistar rats were subjected to ligature placement around the second upper left molars. Animals were treated topically with Ls and/or Mu-based gel, immediately after EPD induction and three times/day for 11 days until the rats were sacrificed (11th day). Saline-based gel was utilized as control for all experiments and doxycycline based gel 10% (w/w) was utilized as reference substance. Animals were weighed daily. Alveolar bone loss was measured as the difference (in millimeters) between the cusp tip and the alveolar bone. The periodontum and the surrounding gingivae were examined at histopathology, as well as the neutrophil influx into the gingivae was assayed using myeloperoxidase activity and cytokine production mainly tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) levels by ELISA method. The local bacterial flora was assessed through culture of the gingival tissue in standard aerobic and anaerobic media. Alveolar bone loss was significantly inhibited by Ls and Mu combined treatment compared to the saline control group. Ls and Mu combined treatment reduced tissue lesion at histopathology, with partial preservation of the periodontum, coupled to decreased myeloperoxidase activity as well as significantly inhibited TNF-alpha and IL-1beta production in gingival tissue compared to the saline control group. Ls and Mu combined treatment also prevented the growth of oral microorganisms and the weight loss. Ls and Mu combined based gel treatment preserved alveolar bone resorption and demonstrated anti-inflammatory and antibacterial activities in experimental periodontitis.

Antimicrobial activity of the essential oil from Lippia sidoides, carvacrol and thymol against oral pathogens

Dental caries and periodontal disease are associated with oral pathogens. Several plant derivatives have been evaluated with respect to their antimicrobial effects against such pathogenic microorganisms. Lippia sidoides Cham (Verbenaceae), popularly known as "Alecrim-pimenta" is a typical shrub commonly found in the Northeast of Brazil. Many plant species belonging to the genus Lippia yield very fragrant essential oils of potential economic value which are used by the industry for the commercial production of perfumes, creams, lotions, and deodorants. Since the leaves of L. sidoides are also extensively used in popular medicine for the treatment of skin wounds and cuts, the objective of the present study was to evaluate the composition and antimicrobial activity of L. sidoides essential oil. The essential oil was obtained by hydro-distillation and analyzed by GC-MS. Twelve compounds were characterized, having as major constituents thymol (56.7%) and carvacrol (16.7%). The antimicrobial activity of the oil and the major components was tested against cariogenic bacterial species of the genus Streptococcus as well as Candida albicans using the broth dilution and disk diffusion assays. The essential oil and its major components thymol and carvacrol exhibited potent antimicrobial activity against the organisms tested with minimum inhibitory concentrations ranging from 0.625 to 10.0 mg/mL. The most sensitive microorganisms were C. albicans and Streptococcus mutans. The essential oil of L. sidoides and its major components exert promising antimicrobial effects against oral pathogens and suggest its likely usefulness to combat oral microbial growth.

Chest mechanics in morbidly obese non-hypoventilated patients

Seventy-seven patients with morbid obesity, body mass index (BMI) 40-69.9 kg m(-2), who were candidates for gastroplasty, were studied in our laboratory as part of a pre-operative survey. They had no complaints other than obesity and were not cyanotic. A group of 28 lean subjects (BMI 20-29.8 kg m(-2)) who were candidates for abdominal surgery, without any respiratory complaint, were included as controls. For each patient a pulmonary function test was performed, measuring slow vital capacity with expiratory residual volume (ERV), forced vital capacity (flow/volume) and maximal voluntary ventilation (MVV). In obese patients the MVV is reduced as BMI increases. This results in the reduction of expiratory flows and volumes. Forced expiratory volume in 1 sec (FEV1) is reduced in proportion to the FVC reduction and is related to MVV. It is suggested that the main consequence of the burden of the chest wall by increased adipose mass is a reduction in its compliance, making inspiration increasingly difficult, and resulting in lower static volumes and flows.