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N A Pocock

Publications and source records attributed to N A Pocock.

39 records · Page 3Linked to original sources

Osteoporosis in rheumatoid arthritis: safety of low dose corticosteroids.

Fear of inducing generalised osteoporosis is one reason why corticosteroids are withheld in patients with rheumatoid arthritis (RA). No studies, however, have directly measured bone density in such patients at clinically relevant sites. To assess this risk we measured bone mineral density in the lumbar spine and femoral neck by dual photon absorptiometry in 84 patients with RA, 44 of whom had been treated with low dose prednis(ol)one (mean dose +/- SE 8.0 +/- 0.5 mg/day; mean duration of treatment 89.6 +/- 12.0 months). There were significant reductions in bone mineral density in patients treated with corticosteroids (lumbar 9.6%, p less than 0.001; femoral 12.2%, p less than 0.001) and in those who had not received corticosteroids (lumbar 6.9%, p less than 0.01; femoral 8.9%, p less than 0.001), but the differences between the two groups were not significant. We conclude on the basis of these studies that low dose oral corticosteroids do not increase the risk of generalised osteoporosis in patients with rheumatoid arthritis.

Adult↗

Physical fitness is a major determinant of femoral neck and lumbar spine bone mineral density.

The relationship between physical fitness and bone mass in the femoral neck, lumbar spine, and forearm was studied in 84 normal women. Femoral neck and lumbar spine bone mineral density and forearm bone mineral content were estimated by absorptiometry. Fitness was quantitated from predicted maximal oxygen uptake. Femoral neck and lumbar bone mineral density were significantly correlated with fitness as well as age and weight. In the 46 postmenopausal subjects, fitness was the only significant predictor of femoral neck bone mineral density, and both weight and fitness predicted the lumbar bone mineral density. These data represent the first demonstration of a correlation between physical fitness, and, by implication, habitual physical activity, and bone mass in the femoral neck; they also support the previous reported correlation between lumbar bone mass and physical activity. The data suggest that increased physical fitness may increase bone mass at the sites of clinically important fractures in osteoporosis.

Adult↗

The acute response of indium-111 labelled platelets to arteriotomy closure.

A standard 40 mm arteriotomy was created in canine iliac and carotid arteries and then closed by either direct suture without a patch, with a vein patch or with a polytetrafluoroethylene patch (PTFE). The uptake of 111-Indium oxine labelled platelets at 2 hours after operation was compared between the groups. Arteriotomies closed with a PTFE patch demonstrated significantly greater platelet aggregation than those closed with a vein patch. Primary closure without a patch was associated with the least platelet uptake of all (PTFE versus vein patch, P less than 0.01; PTFE versus no patch, P less than 0.01; vein patch versus no patch, P less than 0.05). Light and electron microscopy confirmed the radioisotopic findings.

Animals↗