LONGITUDINAL AND GENETIC-EFFECTS IN THE RELATIONSHIP BETWEEN PULMONARY-FUNCTION AND COGNITIVE PERFORMANCE

Previous studies have found cognitive deficits in patients with impair ed pulmonary function, and recent data from healthy older adults sugge st an association of pulmonary function with cognitive function. This 6-year longitudinal study evaluated genetic and environmental sources of covariation in the association of pulmonary function and cognitive performance. The sample included 222 Swedish twin pairs (60% women) wi th a mean age of 62.3 (+/- 7.7) years (age range: 40-84). Hierarchical multiple regression analyses, controlling for the effects of age, gen der, and height, were employed to predict performance on cognitive tes ts of fluid intelligence (Digit Symbol, Block Design, Digit Span-Backw ard) and crystallized intelligence (Information) from forced expirator y volume in one second (FEV1). Bivariate cross-twin correlations were used to evaluate the contribution of genetic and environmental factors in the association of pulmonary function and cognitive performance. R esults indicated that FEV1 predicted performance on tests of fluid int elligence but not crystallized intelligence at the initial assessment and at the 6-year follow-up. Cross-twin correlational analyses indicat ed that genetic effects accounted for a greater share of the associati on of pulmonary function and cognitive performance than environmental effects, but environment also accounted for a substantial share of the covariance.