The study population consisted of 28 adult males from the city of Jos and 44 adult Fulani males from Magama Gumau, a hamlet situated approximately 60 km east of Jos. The Jos subjects, which consisted primarily of individuals from the Hausa, Igbo, Yoruba, and Berom ethnic groups, were recruited from among the staff of the Jos University Teaching Hospital and their relatives. Individuals with a history of tobacco use or who had an upper respiratory infection in the previous six weeks were excluded from the study. Data were collected on location between June and August of 2002, which coincides with the rainy season in Nigeria. Informed consent was obtained for all subjects. The study was approved by the University of New Mexico School of Medicine Human Research Review Committee and the Jos University Teaching Hospital Human Ethics Committee.
Height was measured to within 0.1 cm using a stadiometer. Weight was measured to within 0.5 kg using a portable scale. Mid-arm circumference was measured to within 0.5 cm with a measuring tape from Creative Health Products, Plymouth, MI. Triceps skin-fold thickness measurements from each subject were obtained to within 0.5 mm using a body caliper from The Caliper Company, Carson City, NV.
An SP-1 model Schiller Pulmonary Function Workstation (Schiller AG, Dietikon, Switzerland), a flow-based spirotachometer, was used to measure the following pulmonary function parameters as well as to calculate predicted values using built-in standardized formulas taking into account ethnicity, sex, age, and height: FVC, FEVi, forced expiratory flow during the middle 50% of the FVC (FEF), and PEF. The FVC, which is the volume of air that can be forcefully exhaled after maximal inspiration, is decreased in both obstructive and restrictive pulmonary disease. The FEVi is the volume of air exhaled during the first second of FVC. The procedure by which spirometry data was collected involved the subjects forcibly exhaling the maximum volume of air into the spirometer after full inspiration, allowing the measurement of volume exhaled per unit of time, from which the various pulmonary function parameters were calculated. The spirometer was calibrated daily prior to use with a calibration pump per the manufacturer’s specifications. All measurements were performed in the seated position and with a nose clip in place to close the nares so that only mouth-breathing was possible. Two readings were taken from each subject, and the best of the two data sets was used for analysis.
Data was analyzed and tested for normality using the two-sample Mest and multiple regression using the NCSS 2000 Statistical Analysis System from NCSS Statistical Software, Kayeville, UT. A p-value of <0.05 was considered statistically significant. canadian antibiotics