Disease relevance of Bed Rest

• Atenolol was compared with placebo in a randomised and double-blind prospective study of 120 women with mild to moderate pregnancy-associated hypertension who were also initially managed conventionally by bed rest [1].
• In contrast, inhibition of bone resorption by pamidronate could preserve bone mineral and reduce the risk of renal stone formation during prolonged bed rest [2].
• METHODS: 20 patients with rheumatoid arthritis and knee synovitis were randomised to 24 hour bed rest or to normal activity after intra-articular glucocorticoid treatment [3].
• Twenty-four patients wth peripheral vascular disease unsuitable for surgery and suffering from ischaemic rest pain were treated equally with 14 days of bed rest and intravenous naftidrofuryl and their pain analogue scores and personality structures were analysed [4].
• Compression and walking versus bed rest in the treatment of proximal deep venous thrombosis with low molecular weight heparin [5].

Psychiatry related information on Bed Rest

• Plasma for cortisol determination was obtained from 15 combat veterans with PTSD, 14 subjects with major depression, and 15 normal men every 30 min during a 24-hour period of bed rest [6].
• These studies demonstrate that the limited physical activity dictated by bed rest for as little as seven days is associated with substantial resistance to insulin's effects on glucose metabolism [7].
• Sera from a total of 31 pregnant women, including 16 of the bed-rest therapy group and 15 of the IDI therapy group, were collected at the 4th, 6th, and 8th gestational weeks and were measured for M-CSF levels, using the enzyme-linked immunoadsorbent assay (ELISA) method established by Hanamura et al [8].

High impact information on Bed Rest

• With bed rest, the plasma hypoxanthine level returned to normal within a few hours, and the plasma urate concentration decreased from 18.6 to 10.6 mg per deciliter (1106 to 630 mumol per liter) within 48 hours [9].
• Similarly, the urinary excretion of these purine metabolites was reduced by bed rest [9].
• During a period of bedrest deconditioning in humans, infusions of dobutamine maintain many of the physiologic expressions of physical conditioning [10].
• The effects of intermittent infusions of dobutamine were studied in young normal male subjects during a period of bedrest deconditioning to determine whether this synthetic catechol affects physical conditioning processes in humans [10].
• METHODS: The knees of 97 patients with persistent arthritis despite outpatient treatment with IA GCs (n = 113 knees), were treated with either IA (90)Y plus GCs (50%) or IA placebo yttrium plus GCs (50%), followed by 3 days of bed rest in the hospital clinic, with splinting of the treated knee [11].

Chemical compound and disease context of Bed Rest

• Resistive exercise increased bone formation but was unable to prevent femoral BMD decrease and increases in bone resorption and urinary Ca during bed rest, with formation of renal stones in four of nine subjects [2].
• Notably, no edema was present despite a urinary protein loss of 40 gm. per day resulting in a serum albumin level of 13 gm./l. Conservative treatment after lymphography, including prolonged bedrest and a medium chain triglyceride diet, was unsuccessful [12].
• Pyoderma gangrenosum rapidly progressed and failed to respond to a combined treatment of bed rest, prednisone, sulfasalazine, povidone-iodine, compresses, and debridement [13].
• METHODS: Fifteen patients, including those with rheumatoid arthritis or systemic sclerosis, who had wounds with exposed bones were treated either with the standard procedure, consisting of local wound care, debridement with a scalpel, bed rest and parenteral antibiotics (n = 8), or with a newly developed experimental procedure (n = 7) [14].
• Hospitalization, bed rest, and short- and long-acting nitrates are generally employed in Groups 2 and 3 patients and the marked reduction in myocardial infarction rates from early to recent studies tends to support these approaches [15].

Biological context of Bed Rest

• A 24% decrease in nonoxidative leucine disappearance was seen in subjects assigned to the lower-protein diet, who had been on bed rest, but on the higher-protein diet, leucine kinetics were unchanged by bed rest [16].
• Ibuprofen impaired the NO response to bed rest, producing a small rise in blood pressure [17].
• Heart rate, epinephrine, and PRA responses to upright tilt after bed rest were increased (P < 0.05), despite the fluid load [18].
• The timing of the peak in serum cytidine deaminase concentrations after a period of morning physiotherapy, but not during the bedrest morning, suggests that exercise accounts for the circadian rhythm, probably by increasing the lymphatic clearance from inflamed joints [19].
• After bed rest, LBNP tolerance was reduced in 11 of 13 subjects (P <.023), HR was greater (P <.002), cardiac output was unchanged, and the ability to augment MSNA at high levels of LBNP was reduced (rate of rise for 30- to 60-mmHg LBNP before bed rest 0.073 bursts x min(-1) x mmHg(-1); after bed rest 0.035 bursts x min(-1) x mmHg(-1); P < 0.016) [20].

Anatomical context of Bed Rest

• Muscle biopsies were obtained from the vastus lateralis before and after 84 days of bed-rest from six control (BR) and six resistance-exercised (BRE) men to examine slow- and fast-twitch muscle fibre contractile function [21].
• The cristae to matrix ratio of the mitochondria did not change with bedrest but improved from 0.37 +/- 0.04 to 0.47 +/- 0.05 (P < .02) after dobutamine [22].
• After 52 days of bed rest, FMD and nitroglycerin-mediated dilatation of the superficial femoral artery were increased in both groups, possibly by increased nitric oxide sensitivity [23].
• Resistance training affects GLUT-4 content in skeletal muscle of humans after 19 days of head-down bed rest [24].
• We have been able to show in six subjects that 4 weeks of head-down tilt bed rest induces a significant decrease in interleukin-2 secretion by PHA-stimulated T lymphocytes [25].

Associations of Bed Rest with chemical compounds

• Serum levels of hyaluronan, antigenic keratan sulfate, matrix metalloproteinase 3, and tissue inhibitor of metalloproteinases 1 change predictably in rheumatoid arthritis patients who have begun activity after a night of bed rest [26].
• Prevention of hypercalciuria and stone-forming propensity during prolonged bedrest by alendronate [27].
• Similarly, DPD increased significantly at the onset of bed rest, remained elevated for the duration of bed rest, and returned to pre-bed rest levels upon reambulation [28].
• In contrast to SALP, serum osteocalcin (OC) began increasing the day preceding the increase in Hyp, remained elevated for the duration of the bed rest, and returned to pre-bed rest values within 5 days of reambulation [28].
• Pamidronate (60 mg) was administered intravenously 14 days before bed rest [2].

Gene context of Bed Rest

• Differential expression of nitric oxide synthases (NOS 1-3) in human skeletal muscle following exercise countermeasure during 12 weeks of bed rest [29].
• Decreased insulin sensitivity and insulin-like growth factor-I (IGF-I) bioavalibility, as measured by the serum IGF-I/insulin-like growth factor binding protein-1 (IGFBP-1) ratio, was found after fasting, whereas no metabolic changes were found after bed rest [30].
• Immunoreactive parathyroid hormone showed a modest decrease during bed rest and a significant increase in the recovery period [31].
• Plasma post-heparin lipoprotein lipase activity decreased from 0.494 to 0.418 micromol mL(-1) h(-1) (P < 0.01), but plasma post-heparin hepatic triglyceride lipase activity and cholesterol ester transfer protein activity did not change during bed rest [32].
• OBJECTIVES: To study the effects of 20 days of bed rest on HDL cholesterol, lipoprotein lipase, hepatic triglyceride lipase, cholesterol ester transfer protein and lecithin-cholesterol acyltransferase [32].

Analytical, diagnostic and therapeutic context of Bed Rest

• Using a model of bedrest immobilization, the ability of a potent aminobisphosphonate, alendronate, to avert hypercalciuria and stone-forming propensity was tested [27].
• In a program of studies of disuse osteoporosis, fluoride balances were determined in healthy men during ambulation and then during bed rest for 6 to 17 wk [33].
• After propranolol administration, tolerance to a maximal lower body negative pressure (LBNP) test after bed rest improved to at least the -70 mm Hg level; following this, there was a sharp decrease in tolerance time [34].
• Because of a high 'placebo effect' of simple bed rest, a only small and short lasting additional effect of PMFT and high costs of a PMF-device, we cannot recommend PMFT as an additional feature of a multimodal neurological rehabilitation program in order to reduce fatigue level of MS-patients [35].
• All patients were treated initially with bedrest, fluid resuscitation, extremity elevation, and systemic high-dose heparin therapy [36].

References