Associations between physical fitness and cardiovascular disease in older adults with intellectual disabilities: Results of the Healthy Ageing and Intellectual Disability study.

BACKGROUND: Reduced physical fitness is a cardiovascular disease (CVD) risk factor in the general population. However, generalising these results to older adults with intellectual disabilities (ID) may be inappropriate given their pre-existing low physical fitness levels and high prevalence of co-morbidities. Therefore, the aim of this study is to investigate the difference in physical fitness between older adults with ID with and without CVD. METHOD: Baseline data of a cohort of older adults with borderline to profound ID (HA-ID study) were used (n = 684; 61.6 ± 8.2 years; 51.3% male). CVD status (coronary artery disease, heart failure, stroke) was obtained from medical files. Cardiorespiratory fitness (10-m incremental shuttle walking test), comfortable and fast gait speed (over 5 m distance) and grip strength (hand dynamometer) were measured. Multivariable linear regression models were used to investigate the association between these physical fitness components and the presence of CVD, adjusted for participant characteristics. RESULTS: Of the 684 participants 78 (11.4%) had CVD. Participants with CVD scored lower on cardiorespiratory fitness (-81.4 m, P = 0.002), comfortable gait speed (-0.3 km/h, P = 0.04) and fast gait speed (-1.1 km/h, P = 0.04). No significant differences were found for grip strength (-0.2 kg, P = 0.89). CONCLUSIONS: Older adults with CVD had significantly lower physical fitness levels than those without CVD, except for grip strength. Longitudinal research is needed to investigate causality.

Converting enzyme inhibitors and the role of the sulfhydryl group in the potentiation of exo- and endogenous nitrovasodilators.

In this study, the effect of bradykinin on coronary flow in the isolated rat heart was significantly potentiated when cysteine or the sulfhydryl-containing converting enzyme inhibitors captopril and zofenoprilat were administered simultaneously. In contrast, the effect of concomitant administration of enalaprilat only slightly increased the effect of bradykinin on coronary flow. In nitrate-tolerant hearts of rats pretreated with isosorbide dinitrate (15 mg daily), the increase in coronary flow by nitroglycerin and bradykinin was significantly less when compared to control hearts. The effect of captopril was not affected by pretreatment. The involvement of endothelium-derived relaxing factor (EDRF) in the effect of captopril was apparent from experiments with L-arginine, the precursor of EDRF, and L-NMMA, the "false" precursor of EDRF. L-Arginine increased the effect of captopril, whereas L-NMMA showed a competitive antagonism for the effect of captopril on coronary flow in the isolated rat heart. Clinically, the effect of captopril was studied in 10 patients with stable, exercise-induced angina pectoris that had been treated for 3 weeks with slow-release isosorbide dinitrate (20 mg four times daily). At day 7, a baseline exercise test was obtained. Subsequently, patients with chest pain and at least 1-mm ST-segment depression on the ECG during exercise were included. They received on day 14 and 21 either captopril (25 mg) or placebo 1 h before exercise testing in a randomized, double-blind, crossover design. Captopril significantly improved the combined score of maximal ST-segment depression, maximal workload, and time to angina when compared to placebo. No differences in the pressure-rate index at rest and during exercise were seen. These results indicate that the sulfhydryl group of certain angiotensin converting enzyme inhibitors can potentiate their effect on the endogenous nitrovasodilator EDRF. In the clinical situation, this may lead to an improved exercise performance in patients with stable angina pectoris during chronic nitrate treatment, independent of its systemic vascular effects.

Optimising visual selection in early clonal generations of potato based on genetic and economic considerations.

In 1985, 1986 and 1987, 600 clones were visually assessed at harvest on plant appearance. The clones were harvested 80 days after planting in the first year, in the following years after approximately 80 days as well as after 145 days. The correlation coefficients between years and between harvest times were low to medium. Simulating different selection intensities using the performance of these 600 clones in two successive years, the relation between selection pressure in the first year and the retained proportion of well performing clones in the second year was described. Including the costs of testing, the most economic selection procedure was calculated. This procedure consisted in testing 1,579 first-year clones and 499 second-year clones for every 100 third-year clones required. The optimal period of the main evaluation in the second clonal year is at ware potato harvest time. This selection procedure also provides good selection possibilities for underwater weight and foliage maturity.