Follow-up study of biological parameters in elderly institutionalized patients more than one year after discontinuation of calcium-vitamin D supplementation.

Laboratory tests were done 15 to 19 months after completion of a six-month clinical trial of oral supplementation with 1 g elemental calcium and 800 IU vitamin D per day in elderly institutionalized patients. Serum 25-OH-vitamin D and intact parathyroid hormone levels returned to normal during the trial, indicating efficacy of the supplementation in correcting the vitamin D deficiency and secondary hyperparathyroidism present before the trial. Data were available before, during, immediately after and 15 to 19 months after the trial in 37 patients. Recurrence of the vitamin D deficiency was observed after discontinuation of the supplementation.

Markers of bone remodeling in the elderly subject: effects of vitamin D insufficiency and its correction.

The elderly subject is prone to both vitamin B insufficiency and calcium insufficiency due to a low calcium intake and calcium malabsorption. These two alterations may lead to secondary hyperparathyroidism, and thus to increased bone loss. We investigated 72 elderly subjects (16 men and 56 women) with vitamin D insufficiency and 25 healthy elderly women with normal vitamin D status, with respect to their indices of calcium metabolism and of bone remodeling: serum total alkaline phosphates (phosphatases), bone AP (BAP), osteocalcin (BGP), tartrate-resistant acid phosphatase (TRAP), urine hydroxyproline (HYP), and the 3-OH-pyridinium derivatives pyridinoline (PYD) and deoxypyridinoline (DPD), which are new markers of bone resorption. We then studied the modifications of these markers in the patients with vitamin D insufficiency at 3 months and 6 months after onset of a daily vitamin D and calcium supplementation. When compared with elderly subjects with normal vitamin D status, patients with vitamin D insufficiency had increased intact parathyroid hormone (iPTH) levels (60.1 +/- 10.2 vs 30.2 +/- 4.5, p < 0.001) and a high bone turnover as reflected by increased values of most serum and urine markers of bone remodeling. PYD and DPD levels were significantly correlated with all indices of bone turnover, unlike HYP, which showed no correlation with bone formation markers (AP, BAP, and BGP). A daily supplement of 800 IU vitamin D3 and 1 g of elemental calcium increased 25(OH)D levels and induced a dramatic decrease of iPTH levels; at 3 and 6 months, the mean iPTH level decreased by 50% (p < 0.0001), reaching the mean value of healthy vitamin D sufficient elderly women. All markers of bone turnover, except TRAP, decreased significantly at 3 and 6 months. The PYD/DPD ratio increased significantly at 3 and 6 months. The decrease of bone markers was more marked in patients with more severe hyperparathyroidism, the greatest variations being obtained with BAP (45%, p = 0.006) and DPD (43%, p = 0.036) levels. Most markers of bone remodeling are increased in elderly subjects with vitamin D insufficiently and vary with its correction. However, BAP and DPD are the most sensitive indicators of increased bone turnover due to secondary hyperparathyroidism.

Prevalence and biological consequences of vitamin D deficiency in elderly institutionalized subjects.

The prevalence of vitamin D deficiency was evaluated in a population of elderly institutionalized subjects in seven long-term geriatric care facilities in France (Amiens, Francheville, Ivry, Lille, Montpellier, Oissel and Villejuif). Residents whose functional capability was relatively good were entered into the study. There were 126 patients (99 females and 27 males) with a mean age +/- SD of 84 +/- 6.6 years. All subjects had been institutionalized for over six months and were capable of walking at least as far as the dining room. None had received vitamin D or other compounds known to affect the metabolism of phosphorus and calcium within six months before the study. Vitamin D status was evaluated by determining serum 25 hydroxyvitamin D (25 OH D) levels using a radiocompetition assay after extraction and chromatographic separation. Mean serum 25 OH D was 3.17 +/- 2.52 ng/ml (median 2.5). Eighty-five per cent of subjects had serum 25 OH D values of less than 5 ng/ml and 98% had values under 10 ng/ml, which is the cutoff usually taken to define vitamin D deficiency. Mean serum levels of intact parathyroid hormone were increased approximately two-fold as compared with values in healthy adults (70 +/- 39 pg/ml versus 33 +/- 12 pg/ml). Biochemical markers for bone formation (alkaline phosphatase, osteocalcin) and bone resorption (TRAP, hydroxyproline, pyridinoline) were all increased, with mean values 1.4-fold to 3.4-fold those seen in healthy adults. Serum 25 OH D levels were negatively correlated with serum intact parathyroid hormone levels (r = 0.41; p < 0.0001). Serum intact parathyroid hormone levels were positively correlated with alkaline phosphatase activity (r = 0.30; p < 0.001) and serum osteocalcin levels (r = 0.36; p < 0.0001) and negatively correlated with corrected serum calcium levels (r = -0.20; p < 0.02). Conclusion. Our data demonstrate that severe vitamin D deficiency is present in virtually all elderly institutionalized subjects and is accompanied with secondary hyperparathyroidism responsible for increases in markers of bone remodeling. Routine vitamin D supplementation is warranted in elderly institutionalized subjects.

Evaluation of a new solid formulation of calcium and vitamin D in institutionalized elderly subjects. A randomized comparative trial versus separate administration of both constituents.

Supplementation with 800 IU of vitamin D and 1 g of calcium each day is recommended in institutionalized elderly subjects to prevent secondary hyperparathyroidism and its adverse skeletal effects. An original formulation (IDEOS) combining vitamin D and calcium has been developed for use in this end. The aim of this study was to determine whether administration of this association, of which each tablet contains 500 mg calcium and 400 IU vitamin D3, produces the same beneficial effects on laboratory parameters as separate administration of both active agents. A multicenter randomized study was conducted in 91 elderly institutionalized subjects (mean age 83.1 years) who had vitamin D deficiency [25-(OH)D < 6 ng/ml] without severe renal failure. Subjects were randomly assigned to one of the two treatment groups. Treatment duration was six months. One group (G1, n = 46) received one tablet of the new formulation twice daily. The other (G2, n = 45) received 8 drops of vitamin D3 (800 IU/day) and one calcium carbonate 500 mg tablet twice daily. Blood tests were carried out at inclusion and after three and six months of treatment. In group G1, plasma 25-(OH)D levels increased from 2.6 ng/ml at inclusion to 14.6 ng/ml at month 6 (p < 0.001), and iPTH fell from 63.2 pg/ml at inclusion to 33.8 pg/ml at month 6 (p < 0.001). In group G2, 25-(OH)D rose from 2.8 ng/ml at inclusion to 13.5 ng/ml at month 6 (p < 0.001), and iPTH fell from 55.4 pg/ml at inclusion to 32.5 pg/ml at month 6 (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)