BODY-WEIGHT AND WEIGHT-GAIN RELATED TO PULMONARY-FUNCTION DECLINE IN ADULTS - A 6 YEAR FOLLOW-UP-STUDY

Background-Obesity increases the risk of cardiovascular disease, hyper tension, diabetes, digestive diseases, and some cancers. Several studi es have shown that excess weight or weight gain is related to pulmonar y dysfunction, but this issue needs to be further clarified. Methods-T he analysis was based on data of the Humboldt cohort study which was c onducted in the town of Humboldt, Saskatchewan, Canada. The baseline s urvey in 1977 included 1202 adults, comprising 94% of all residents ag ed 25-59 years. Of these, 709 (59%) were followed up in 1983. Pulmonar y function (forced vital capacity (FVC), forced expiratory volume in o ne second (FEV1) and maximal mid expiratory flow rate (MMFR)) and weig ht were measured in both, surveys. Weight gain was determined by subtr acting weight at baseline from weight at follow up. A residual analysi s was used to examine the relationship between body mass index (BMI) a t baseline, weight gain, and pulmonary function decline. Results-Both BMI at baseline and weight gain were significantly related to pulmonar y function at follow up. The effect of weight gain during the study pe riod, however, was more prominent. The results showed that both mean r esidual FVC and FEV1 were highest in the group that gained <1.0 kg, lo west in the group that gained greater-than-or-equal-to 4.0 kg, and int ermediate in the group that gained 1.0-3.9 kg in both men and women af ter taking age, BMI at baseline, and smoking into account. The effect of weight gain on pulmonary function was greater in men than in women. Multiple regression analysis showed that each kilogram of weight gain was associated with an excess loss of 26 ml in FVC and 23 ml in FEV1 in men, and 14 ml and 9 ml respectively in women. Conclusions-Weight g ain is significantly related to lung dysfunction. The effect of weight gain on pulmonary function is greater in men than in women.