Search

Bisphosphonates are known to be potent inhibitors of osteoclast activity and their only clinically relevant effect in the short-term is the selective inhibition of bone resorption. The purpose of this study was to compare the response to the intravenous administration of two bisphosphonates, clodronate and alendronate, of several biochemical markers of bone resorption, including tartrate-resistant acid phosphatase (TRAP) and cross-linked carboxyterminal telopeptide of collagen I (ICTP) in serum and hydroxyproline (OHP), free pyridinium cross-links (Pyr), and crosslinked N-telopeptides of collagen I (NTx) in urine. The study was carried out on 11 osteoporotic and 12 Pagetic subjects of both sexes, treated with clodronate (600 mg/day for 2 days) or alendronate (5 mg/day for 2 days), and monitored for 28 days after bisphosphonate administration. All the urinary markers of bone resorption showed a prompt decline after bisphosphonates, with maximum reductions after 7–14 days: Pyr decreased by 43%±9% and 42%±22% (mean ± SD), respectively in osteoporotic and pagetic subjects, OHP by 51%±14% and 51%±20%, and NTx by 55%±15% and 65%±26%. In the osteoporotic group, the urinary markers began to increase again at 30 days, though still remaining well below the basal level, whereas in the pagetic group, the excretion of all markers remained depressed until the end of the observation period. The reduction of NTx was significantly greater than that of Pyr and OHP in pagetic patients (P

The purpose of this study was to examine the serum levels of bone alkaline phosphatase (BALP) measured with a new assay in normal and in osteoporotic women, and to evaluate prospectively its responsiveness to changes of bone metabolism. The following groups of subjects were studied: (1) 95 healthy women (44–75 years) (22 pre- and 73 postmenopausal) and 35 osteoporotic women [vertebral bone mineral density (BMD) more than 2.5 SD below the normal adult mean]; (2) 10 women (44–50 years) ovariectomized (OVX) for benign uterine diseases, examined before and 12 months after surgery; (3) 16 OVX women (36–54 years), examined before and after 12 months of transdermal estrogen replacement therapy (50 μg/day); (4) 12 previously untreated pagetic patients (4 women and 8 men, 50–80 years), examined before and 3 months after the I.V. administration of clodronate (600 mg) or alendronate (5 mg) for 2 consecutive days. The median BALP value was 11.6 U/liter (25–75th percentiles: 10.5–12.7; range 7.7–19.3) in healthy premenopausal (PreMP) women and significantly higher (median: 16.8 U/liter; 25–75th percentile: 13.8–21.8; P < 0.01) in postmenopausal (PostMP) women. There was a clear age-related increase in normal subjects (r = 0.43; P < 0.001). In the osteoporotic group, BALP levels, as well as other biochemical parameters of bone turnover, were not significantly different from those of normal women when adjusted for age. In OVX women, BALP levels showed a marked increase 12 months after surgery (median: 113%; 25–75th percentile: 87–139%), significantly higher than the increase of total ALP (median: 43%; 25–75th percentile: 25–66%; P < 0.001), and similar to the increases of serum osteocalcin and urinary hydroxyproline. Transdermal estrogen treatment prevented the BALP increase, even if no reduction was observed; total ALP showed a similar behavior. The basal levels of BALP were significantly elevated in pagetic patients (median: 91 U/liter; range 18–610 U/liter) and correlated to the scintigraphic extent of the disease (r = 0.76; P < 0.01). Three months after the I.V. administration of bisphosphonates, the decrease of BALP was more marked than that of total ALP (median: −54% versus −41%; P < 0.05). In conclusion, these results suggest that BALP measurement with this immunoassay may be clinically useful, and more sensitive than total ALP, in the assessment of bone turnover during changes of the estrogen status as well as in monitoring the effects of treatments that modify the metabolic activity of the skeleton.

Fractures of the femoral neck are one of the most important and severe complications of osteoporosis. To obtain up-to-date estimates on the frequency of these fractures in the province of Parma, a city of northern Italy, a retrospective study on the incidence of hip fractures has been carried out examining the operative records of all the orthopedic departments serving the whole province. Between January 1980 and December 1992, 3774 operations for hip fractures were performed, with a marked prevalence in women (2830 women and 944 men) and an exponential increase with age in both sexes. The incidence of extracapsular hip fractures was slightly higher and in women increased more rapidly with age than intracapsular fractures. Approximately 3 fractures out of 4 in women and 2 out of 3 in men occurred after the age of 75. Between 1980 and 1992, the age-adjusted annual incidence rose significantly by 7.1 cases per 100,000 per year in women and by 2.7 cases per 100,000 per year in men. When compared to other populations, these estimates indicate that the incidence of hip fractures in this province of Northern Italy is lower than that reported in other countries, especially in Northern Europe.

Though some reports suggest the existence of seasonal changes in hip fracture incidence, with a peak in winter months, other investigations have failed to confirm this finding. In this study we present data on the month-to-month variability of hip fractures in Emilia-Romagna, a region of Northern Italy with a population of approximately four million inhabitants, and in Parma, a province of Emilia-Romagna (population of approximately 400,000). Data on cervical and trochanteric fractures were obtained from two sources: a) records of all operative procedures in the five orthopaedic centres serving the area of the Parma province; and b) a computerised database of all hospital discharges from public an private hospitals of Emilia-Romagna. In both cases, the analysis gave similar results, with no evidence of a consistent seasonal pattern in hip fracture rates.