Relationship between oral glucose tolerance and gastric emptying in normal healthy subjects

The relationships between gastric emptying and intragastric distribution of glucose and oral glucose tolerance were evaluated in 16 healthy volunteers. While sitting in front of a gamma camera the subjects drank 350 ml water containing 75 g glucose and 20 MBq 99mTc-sulphur colloid. Venous blood samples for measurement of plasma glucose, insulin and gastric inhibitory polypeptide were obtained at--2, 2,5,10,15,30,45,60,75,90,105,120 and 150 min. Gastric emptying approximated a linear pattern after a short lag phase (3.3 +/- 0.8 min). The 50% emptying time was inversely related to the proximal stomach 50% emptying time (r = -0.55, p < 0.05) and directly related to the retention in the distal stomach at 120 min (r = 0.72, p < 0.01). Peak plasma glucose was related to the amount emptied at 5 min (r = 0.58, p < 0.05) and the area under the blood glucose curve between 0 and 30 min was related to the amount emptied at 30 min (r = 0.58, p < 0.05). In contrast, plasma glucose at 120 min was inversely related to gastric emptying (r = -0.56, p < 0.05) and plasma insulin at 30 min (r = -0.53, p < 0.05). Plasma insulin at 120 min was inversely related (r = -0.65, p < 0.01) to gastric emptying. The increase in plasma gastric inhibitory polypeptide at 5 min was related directly to gastric emptying (r = 0.53, p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Gastric and oesophageal emptying in patients with type 2 (non-insulin-dependent) diabetes mellitus

Gastric emptying of a digestible solid and liquid meal and oesophageal emptying of a solid bolus were measured with scintigraphic techniques in 20 randomly selected Type 2 (non-insulin-dependent) diabetic patients receiving oral hypoglycaemic therapy and 20 control subjects. In the diabetic patients, the relationships between oesophageal emptying, gastric emptying, gastrointestinal symptoms, autonomic nerve function and glycaemic control were examined. The percentage of the solid meal remaining in the stomach at 100 min (p less than 0.001), the 50% gastric emptying time for the liquid meal (p less than 0.05) and oesophageal emptying (p less than 0.05) were slower in the diabetic patients compared to the control subjects. Scores for upper gastrointestinal symptoms and autonomic nerve dysfunction did not correlate significantly (p greater than 0.05) with oesophageal, or gastric emptying. The 50% gastric emptying time for the liquid meal was positively related (r = 0.58, p less than 0.01) to the plasma glucose concentration at the time of the performance of the gastric emptying test and the lag period, before any solid food emptied from the stomach, was longer (p less than 0.05) in subjects with plasma glucose concentrations during the gastric emptying measurement greater than the median, compared to those with glucose concentrations below the median. These results indicate that delayed gastric and oesophageal emptying occur frequently in Type 2 diabetes mellitus and that delayed gastric emptying relates, at least in part, to plasma glucose concentrations.

Relationships between oesophageal transit and solid and liquid gastric emptying in diabetes mellitus

In 87 randomly selected diabetic patients (67 type 1, 20 type 2) and 25 control subjects, gastric emptying of digestible solid and liquid meals and oesophageal transit of a solid bolus were measured with scintigraphic techniques. Gastrointestinal symptoms, autonomic nerve function and glycaemic control were evaluated in the diabetic patients. Gastric emptying and oesophageal transit were slower (P less than 0.001) in the diabetic patients compared with the control subjects, and each was delayed in about 40% of them. There was a relatively weak (r = 0.32; P less than 0.01) relationship between solid and liquid gastric emptying, and no significant correlation (r = 0.11, NS) between oesophageal transit and gastric emptying of the solid meal. Scores for upper gastrointestinal symptoms and autonomic nerve function correlated weakly (r = 0.21; P less than 0.05) with both oesophageal transit and gastric emptying. Gastric emptying of the liquid meal was slower (P less than 0.05) in patients with blood glucose concentrations greater than 15 mmol/l. These results indicate that gastric emptying in patients with diabetes mellitus should be assessed by liquid as well as by solid test meals and that oesophageal transit should not be used as a predictor of generalised diabetic gastroenteropathy.

Gastric emptying in diabetes: clinical significance and treatment

The outcome of recent studies has led to redefinition of concepts relating to the prevalence, pathogenesis and clinical significance of disordered gastric emptying in patients with diabetes mellitus. The use of scintigraphic techniques has established that gastric emptying is abnormally slow in approx. 30-50% of outpatients with long-standing Type 1 or Type 2 diabetes, although the magnitude of this delay is modest in many cases. Upper gastrointestinal symptoms occur frequently and affect quality of life adversely in patients with diabetes, although the relationship between symptoms and the rate of gastric emptying is weak. Acute changes in blood glucose concentration affect both gastric motor function and upper gastrointestinal symptoms. Gastric emptying is slower during hyperglycaemia when compared with euglycaemia and accelerated during hypoglycaemia. The blood glucose concentration may influence the response to prokinetic drugs. Conversely, the rate of gastric emptying is a major determinant of post-prandial glycaemic excursions in healthy subjects, as well as in Type 1 and Type 2 patients. A number of therapies currently in development are designed to improve post-prandial glycaemic control by modulating the rate of delivery of nutrients to the small intestine.

Acute and chronic effects of domperidone on gastric emptying in diabetic autonomic neuropathy

Gastric emptying was studied with a double radioisotopic method in 12 patients with insulin-dependent diabetes mellitus complicated by autonomic neuropathy and in 22 control subjects. In the diabetics, the acute and chronic effects of oral domperidone on gastric emptying, symptoms of gastroparesis, and glycemic control were assessed. Gastric emptying of solid and liquid was slower in diabetics than controls (P less than 0.001). Acute administration of domperidone increased the rate of both solid and liquid emptying (P less than 0.005). Domperidone was most effective in those patients with the greatest delay in gastric emptying. After chronic administration (35-51 days), domperidone had no significant effect on solid emptying (P greater than 0.05), but was still effective in increasing liquid emptying (P less than 0.025). Symptoms of gastroparesis were less after domperidone (P less than 0.001).

Effect of cisapride on gastric and esophageal emptying in insulin-dependent diabetes mellitus

The effects of cisapride on gastric emptying, esophageal emptying, gastrointestinal symptoms, and glycemic control were evaluated in 20 insulin-dependent diabetics who had delayed gastric emptying of the solid or liquid component of a meal, or both. A double-isotope technique was used to measure gastric emptying, and esophageal emptying was measured as the time for a bolus of the solid meal to enter the stomach. On 2 days each patient received cisapride (20 mg) or placebo orally, 60 min before an esophageal and gastric emptying test. A third gastric and esophageal emptying test was performed after each patient had orally taken 10 mg of cisapride or placebo q.i.d. for 4 wk. Single-dose cisapride increased esophageal emptying (p less than 0.01) and both solid and liquid gastric emptying (p less than 0.001). The response to cisapride was most marked in patients with the greatest delay in esophageal and gastric emptying (p less than 0.05). After administration of cisapride for 4 wk, gastric emptying of solid and liquid were faster (p less than 0.001), but esophageal emptying was not significantly different from the placebo test. Upper gastrointestinal symptoms were less after cisapride (p less than 0.05), whereas there was no change on placebo (p greater than 0.2). Plasma glucose and glycosylated hemoglobin concentrations were not different after cisapride compared with placebo. These results indicate that single-dose cisapride increases esophageal emptying in insulin-dependent diabetics and that chronic administration of cisapride is effective in the treatment of diabetic gastroparesis.

Changes in gastric emptying rates with age

A dual isotope technique which measures simultaneously the emptying of solids and liquids by the stomach was used to study gastric emptying in 35 subjects in the age range 21-84 years, who were all fit, mobile volunteers and were not taking any drugs. Solid and liquid emptying were significantly slower in older subjects, but this finding is unlikely to be of clinical significance because the changes were small and emptying rates were usually within the normal range for younger subjects.

Effect of the once-daily human GLP-1 analogue liraglutide on appetite, energy intake, energy expenditure and gastric emptying in type 2 diabetes

AIMS

Liraglutide reduces bodyweight in patients with type 2 diabetes mellitus (T2DM). This study aimed to investigate the mechanisms underlying this effect.

METHODS

The comparative effects of liraglutide, glimepiride and placebo on energy intake, appetite, nausea, gastric emptying, antral distension, bodyweight, gastrointestinal hormones, fasting plasma glucose and resting energy expenditure (REE), were assessed in subjects with T2DM randomised to treatment A (liraglutide-placebo), B (placebo-glimepiride) or C (glimepiride-liraglutide). Assessments were performed at the end of each 4-week treatment period.

RESULTS

Energy intake was less (NS) with liraglutide vs placebo and glimepiride, and 24-h REE was higher (NS) with liraglutide vs placebo and glimepiride. Fasting hunger was less (p=0.01) with liraglutide vs placebo and glimepiride, and meal duration was shorter with liraglutide (p=0.002) vs placebo. Paracetamol AUC(0-60 min) and C(max) were less (p<0.01) and fasting peptide YY was lower (p ≤ 0.001) after liraglutide vs placebo and glimepiride. Bodyweight reductions of 1.3 and 2.0 kg were observed with liraglutide vs placebo and glimepiride (p<0.001). There were no differences on antral distension, nausea, or other gastro-intestinal hormones.

CONCLUSION

Liraglutide caused decreased gastric emptying and increased reduction in bodyweight. The mechanisms of the liraglutide-induced weight-loss may involve a combined effect on energy intake and energy expenditure.

Gastric and oesophageal emptying in insulin‐dependent diabetes mellitus

Abstract Gastric emptying of a digestible solid and liquid meal and oesophageal emptying of a solid bolus were measured with scintigraphic techniques in 45 randomly selected insulin‐dependent diabetics and in 22 control subjects. In the diabetics, the relationships between oesophageal emptying, gastric emptying, age, duration of diabetes mellitus, upper gastrointestinal symptoms, glycaemic control and the complications, autonomic neuropathy, peripheral neuropathy and retinopathy were examined. The lag period before solid food left the stomach was not significantly different in diabetics compared with control subjects, but the percentage retention of solid food at 100 min was greater (P < 0.001) in the diabetic subjects. Both the early phase (percentage retention at 10 min) and the 50% emptying time for liquid gastric emptying were delayed (P < 0.001) in the diabetic subjects. Of the diabetics, 58% had delayed gastric emptying of either the solid and/or the liquid meal; oesophageal emptying was delayed in 42%. Upper gastrointestinal symptoms correlated poorly with both gastric and oesophageal emptying. Oesophageal emptying, solid gastric emptying and the liquid 50% emptying time correlated with the severity of autonomic nerve dysfunction (P < 0.05). The early phase of liquid emptying (retention at 10 min) was significantly slower (P < 0.05) in patients with mean plasma glucose concentrations of > 15 mmol/l during the gastric emptying test and the lag period for solid emptying correlated with both the glycosylated haemoglobin and mean plasma glucose concentrations.

The effect of posture on gastric emptying and intragastric distribution of oil and aqueous meal components and appetite

BACKGROUND

It is uncertain whether gastric emptying of fat is determined mainly by its physical characteristics or chemical composition. In particular, the intragastric distribution of extracellular fat and the importance of that distribution to gastric emptying of fat is controversial. The effects of posture on gastric emptying, intragastric distribution, and appetite after ingestion of a meal containing oil and aqueous phases was evaluated.

METHODS

Eleven volunteers consumed 60 mL 99mTc-(V)-thiocyanate-labeled olive oil and 290 mL 113mIn-labeled soup while sitting and while lying in the left lateral decubitus position. Hunger before and after the meal was recorded.

RESULTS

In the sitting position, oil emptied from the stomach more slowly (P < 0.01) whereas in the decubitus position oil emptied faster (P < 0.01) than the aqueous phase. Oil was preferentially retained in the proximal stomach when sitting (P < 0.01), and more oil was retained in the distal stomach in the decubitus position (P < 0.05). The amount of oil that emptied in the first 180 minutes was not different between the two postures. The aqueous phase emptied much more slowly (P < 0.01) in the decubitus position. At 120 minutes and 180 minutes, subjects were less hungry (P < 0.05) in the decubitus position. In the decubitus position, hunger at 120 minutes and 180 minutes was related to the retention of oil (r > or = 0.79; P < 0.01) in the stomach.

CONCLUSIONS

These results indicate that (1) gravity has a major effect on the intragastric distribution and relatively little effect on total stomach emptying of oil, and (2) postprandial hunger is affected by posture and, in the decubitus position, is inversely related to the amount of oil that has entered the small intestine.

Disordered gastric motor function in diabetes mellitus

The application of novel investigative techniques has demonstrated that disordered gastric motility occurs frequently in diabetes mellitus. Gastric emptying is abnormal in about 50% of diabetic patients and delay in gastric emptying of nutrient-containing meals is more common than rapid emptying. The blood glucose concentration influences gastric motility in diabetes. In IDDM patients, gastric emptying is retarded during hyperglycaemia and may be accelerated by hypoglycaemia. Gastroparesis therefore does not necessarily reflect irreversible autonomic neuropathy and blood glucose concentrations must be monitored when gastric motility is evaluated in diabetic patients. There is a poor relationship between gastric emptying and gastrointestinal symptoms and the mechanisms by which abnormal motility causes symptoms are unclear. The introduction of new gastrokinetic drugs has improved therapeutic options for the management of symptomatic patients with gastroparesis considerably. The contribution of disordered gastric emptying to poor glycaemic control is unclear, but the demonstration that the rate of gastric emptying is a major factor in normal blood glucose homeostasis suggests that this is likely to be significant.

Effects of cisapride on gastric and esophageal emptying in progressive systemic sclerosis

The effects of cisapride on gastric emptying, esophageal emptying, and gastrointestinal symptoms were evaluated in 8 patients with progressive systemic sclerosis who had delayed gastric emptying of the solid or liquid component of a meal, or both. A double-isotope technique was used to measure gastric emptying, and esophageal emptying was measured as the time for a bolus of the solid meal to enter the stomach. Gastrointestinal symptoms were assessed by a questionnaire. On 2 days each patient received cisapride (10 mg) or placebo intravenously, 5 min before an esophageal and gastric emptying test. After these 2 days each subject took cisapride (10 mg q.i.d., p.o.) for 1 mo. Cisapride improved solid and liquid gastric emptying (p less than 0.001), but had no significant effect on esophageal emptying (p less than 0.1). Upper gastrointestinal symptoms were reduced after cisapride (p less than 0.001), and no side effects were reported. These results indicate that gastroparesis is a treatable cause of morbidity in progressive systemic sclerosis.

Osteoporosis and Klinefelter's syndrome

OBJECTIVE

We wanted to measure forearm mineral density and bone-related biochemical variables in patients with Klinefelter's syndrome.

DESIGN

Measurements made in patients with Klinefelter's syndrome were compared to those obtained in age-matched normal male volunteers.

PATIENTS

We studied 22 patients with Klinefelter's syndrome (12 of whom had received sex hormone therapy) and 22 control subjects.

MEASUREMENTS

We measured forearm mineral density, forearm fat content, fat-corrected forearm mineral density, plasma calcium and ionized calcium, serum osteocalcin, testosterone and dehydroepiandrosterone sulphate, and urinary hydroxyproline/creatinine ratio.

RESULTS

Forearm mineral density was lower in the Klinefelter's group than in the control subjects (P less than 0.05) and below the control range in 5 patients. The fat content of the forearm was greater in the Klinefelter's group (P less than 0.002). Serum osteocalcin and testosterone were lower, while ionized calcium and the urinary hydroxyproline/creatinine ratio were higher in the Klinefelter's group (P less than 0.002). Serum dehydroepiandrosterone sulphate and testosterone were significantly related in the Klinefelter's group (r = 0.64, P less than 0.001), but not in the controls (r = 0.22, NS). Forearm mineral density and fat-corrected forearm mineral density were significantly related to serum testosterone in the Klinefelter's group (r less than 0.63; P less than 0.01), but not in the control subjects (r less than 0.03, NS).

CONCLUSIONS

Decreased bone density occurs in about 25% of patients with Klinefelter's syndrome and probably reflects both decreased bone formation and increased bone resorption.

The effect of short-term dietary supplementation with glucose on gastric emptying of glucose and fructose and oral glucose tolerance in normal subjects

Recent observations indicate that gastric emptying may be influenced by patterns of previous nutrient intake. The aims of this study were to determine the effects of a high glucose diet on gastric emptying of glucose and fructose, and the impact of any changes in gastric emptying on plasma concentrations of glucose, insulin and gastric inhibitory polypeptide in response to glucose and fructose loads. Gastric emptying of glucose and fructose (both 75 g dissolved in 350 ml water) were measured in seven normal volunteers on separate days while each was on a "standard' diet and an identical diet supplemented with 440 g/day of glucose for 4-7 days. Venous blood samples for measurement of plasma glucose, insulin and gastric inhibitory polypeptide levels were taken immediately before and for 180 min after ingestion of glucose and fructose loads. Dietary glucose supplementation accelerated gastric emptying of glucose (50% emptying time 82 +/- 8 vs 106 +/- 10 min, p = 0.004) and fructose (73 +/- 9 vs 106 +/- 9 min, p = 0.001). After ingestion of glucose, plasma concentrations of insulin (p < 0.05) and gastric inhibitory polypeptide (p < 0.05) were higher during the glucose-supplemented diet. In contrast, plasma glucose concentrations at 60 min and 75 min were lower (p < 0.05) on the glucose-supplemented diet. We conclude that short-term supplementation of the diet with glucose accelerates gastric emptying of glucose and fructose, presumably as a result of reduced feedback inhibition of gastric emptying from small intestinal luminal receptors. More rapid gastric emptying of glucose has a significant impact on glucose tolerance.

Gastroparesis: prevalence, clinical significance and treatment

The application of novel techniques to quantify gastric motor function and gastric emptying has yielded important insights into the prevalence, pathogenesis and clinical sequelae of gastroparesis. Both acute and chronic gastroparesis occur frequently; gastric emptying of solids is delayed in 30% to 50% of patients with diabetes mellitus, functional dyspepsia and gastroesophageal reflux disease. While many patients with gastroparesis experience upper gastrointestinal symptoms that adversely affect quality of life, the concept that symptoms are inevitably the direct outcome of delay in gastric emptying is now recognized to be overly simplistic. In contrast, the potential impact of gastroparesis on oral drug absorption and blood glucose control in patients with diabetes mellitus has probably been underestimated. While the use of prokinetic drugs (cisapride, domperidone, metoclopramide and erythromycin) forms the mainstay of therapy in symptomatic patients with gastroparesis, a number of novel pharmacological therapies are being evaluated, and preliminary studies using gastric pacing show promise.

Measurement of gastric emptying after gastric bypass surgery using radionuclides

The pattern of gastric emptying has been assessed after gastric bypass surgery using a double isotope technique for measuring solid and liquid emptying with a scintillation camera. Eleven control subjects and 12 patients, 12 months post-gastric bypass, were studied. Stomal and gastric pouch size were assessed at endoscopy. Solid emptying was slower and liquid emptying was more rapid after gastric bypass surgery. Initial rapid emptying of solid occurred in the 4 patients with the smallest pouch diameters. There was no correlation between stomal size and rates of solid or liquid emptying nor between the weight loss produced by the operation and the rates of solid or liquid emptying, stoma or pouch size.

Upper and/or lower gastrointestinal adverse events with glucagon-like peptide-1 receptor agonists: Incidence and consequences

AIMS

To characterize gastrointestinal adverse events (AEs) with different glucagon-like peptide-1 receptor agonists (GLP-1RAs).

METHODS

Two retrospective intention-to-treat analyses of 6-month patient-level data were conducted. Data from three studies comparing exenatide once weekly (n = 617) with exenatide twice daily (n = 606) were pooled, and one (DURATION-6) comparing exenatide once weekly (n = 461) with liraglutide (n = 450) was analysed separately. Patient-reported gastrointestinal AEs were classified as upper or lower, AE incidences and timing were determined, subgroups were analysed, and associations of gastrointestinal AEs with efficacy were examined.

RESULTS

Nausea was the most common gastrointestinal AE for all treatments. Fewer exenatide once-weekly-treated vs exenatide twice-daily- or liraglutide-treated patients reported gastrointestinal AEs (34% vs 45% and 25% vs 41%, respectively; both P  < .0001). Fewer exenatide once-weekly-treated patients reported upper plus lower events than liraglutide-treated patients ( P  < .001); the difference between exenatide once weekly and twice daily was not significant. Within each group, more women than men reported gastrointestinal AEs. Events occurrred early and were predominantly mild. Glycated haemoglobin reductions were similar for patients with or without gastrointestinal AEs. Weight loss was greater for patients with gastrointestinal AEs with exenatide once weekly and exenatide twice daily ( P  < .05); no difference was observed in DURATION-6.

CONCLUSIONS

Gastrointestinal AEs were less frequent with exenatide once weekly vs exenatide twice daily or liraglutide, and combined upper and lower events occurred less often. Gastrointestinal AEs were typically mild and occurred early. Gastrointestinal AEs did not affect glycaemic control but may be associated with greater weight loss.

The normal menstrual cycle has no effect on gastric emptying

Recent studies have demonstrated that orocaecal transit time is prolonged both in the luteal phase of the ovulatory cycle in normal women and during pregnancy, but have made no attempt to differentiate between the individual effects of gastric emptying and small intestinal transit. We have assessed the effect of the normal menstrual cycle on gastric emptying of solids and liquids in 10 women, using a dual isotope scintigraphic technique. In each subject gastric emptying was measured on 2 days: first during the follicular phase (day 8-10) and then during the luteal phase (day 18-20) of one ovulatory menstrual cycle (where day 1 was the first day of menstrual bleeding). Measures of solid and liquid gastric emptying did not change significantly between the follicular and luteal phases indicating that the normal menstrual cycle has no effect on gastric emptying.

Abnormalities of gastric and esophageal emptying in polymyositis and dermatomyositis

Gastric and esophageal emptying were assessed using scintigraphic techniques in 13 patients with polymyositis or dermatomyositis and in 13 normal volunteers. Esophageal emptying was significantly delayed in patients, with 8 of 13 patients being outside the normal range. Gastric emptying was also markedly slower in patients than in controls, with 8 patients being outside the normal range for solid emptying and 8 patients beyond the normal range for liquid emptying. The 5 patients with dysphagia all had delayed esophageal emptying, but both gastric and esophageal emptying were delayed in some asymptomatic patients. There was a significant correlation between esophageal emptying and both solid and liquid gastric emptying in the patients. Both gastric and esophageal emptying correlated with the severity of the peripheral (skeletal) muscle weakness. These results indicate that profoundly delayed gastric and esophageal emptying are common in polymyositis and dermatomyositis, implying frequent malfunction of the smooth muscle of the upper gastrointestinal tract in this disease.

Mechanisms and clinical efficacy of lixisenatide for the management of type 2 diabetes

INTRODUCTION

"Incretin-based" therapies, such as the glucagon-like peptide-1 (GLP-1) receptor agonists, represent a major advance in type 2 diabetes mellitus (T2DM) treatment. GLP-1 receptor agonists differ substantially in their duration of action, frequency of administration and clinical profile.

METHODS

This article reviews the mechanisms of action and clinical evidence for GLP-1 receptor targeting and discusses differences between GLP-1 therapies, focusing particularly on clinical data for the GLP-1 receptor agonist, lixisenatide.

RESULTS

GLP-1 therapies target islet cell "defects" of insufficient insulin and excessive glucagon secretion in T2DM, in a glucose-dependent manner, with minimal risk of hypoglycemia. Different GLP-1 therapies exert differential effects on fasting and postprandial glycemia (both being major determinants of glycemic control). They also slow gastric emptying to different extents, probably accounting for different effects to reduce postprandial glycemia. The GetGoal phase 3 studies in T2DM have confirmed the efficacy of once-daily lixisenatide in reducing plasma glucose and glycated hemoglobin (HbA1c), with a pronounced lowering of postprandial plasma glucose (PPG), as monotherapy and as add-on to oral antidiabetic drugs and to basal insulin. Lixisenatide's ability to diminish PPG is probably partly mediated by its marked ability to delay gastric emptying. Lixisenatide is generally well tolerated, with possibly better gastrointestinal tolerability and lower risk of hypoglycemia than exenatide immediate release. Lixisenatide is associated with a beneficial effect on weight, with either no change or a decrease in body weight when administered as add-on therapy to basal insulin in overweight patients with T2DM.

CONCLUSIONS

Lixisenatide improves glycemic control, by primarily affecting PPG, while preventing weight gain or reducing body weight with a low risk of hypoglycemia in T2DM. Lixisenatide is likely to represent a significant advance in the management of T2DM, perhaps particularly in those patients with relatively faster gastric emptying and lower levels of HbA1c, including those receiving basal insulin.

Effect of calcium supplementation on urinary hydroxyproline in osteoporotic postmenopausal women

Although calcium supplements are widely used to reduce bone resorption in osteoporosis, their beneficial effect is not conclusively established. We studied the effect of a calcium supplement (1 g/day for 8 days) in 14 postmenopausal osteoporotic women. The fasting urinary hydroxyproline/creatinine ratio decreased from 0.022 +/- 0.001 to 0.017 +/- 0.001 (p less than 0.005) indicating a significant reduction in bone resorption. Both the tubular maximum for phosphate reabsorption (1.12 +/- 0.06 to 1.34 +/- 0.07, p less than 0.005) and plasma phosphate concentration (1.04 +/- 0.04 to 1.14 +/- 0.04, p less than 0.01) increased, consistent with suppression of parathyroid hormone activity. These results support the concept that calcium supplementation is useful in the treatment of postmenopausal osteoporosis.