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Diss Factsheets

Administrative data

Endpoint:
epidemiological data
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
other: Any kind of reliability rating is not considered to be applicable, since human epidemiological studies, field studies and case reports are not conducted/reported according to standardised guidelines
Rationale for reliability incl. deficiencies:
other: Reliability rating according to Klimisch is not applicable for studies in humans.

Data source

Reference
Reference Type:
publication
Title:
Effects of oral supplementation with stable strontium
Author:
Skoryna, S.
Year:
1981
Bibliographic source:
Can. Med. Assoc. J. 125: 703-712.

Materials and methods

Study type:
cross sectional study
Endpoint addressed:
repeated dose toxicity: oral
Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Clinical studies began by determining strontium and calcium levels in 100 subjects who were receiving a regular diet that supplied approximately 1 g of calcium and 1 to 2 mg of strontium a day. Then, 0.1 to 1.5 g/d of strontium gluconate (183 to 274 mg strontium) were administered for periods of at least 3 months to 50 of these patients with various conditions that might be affected by stable strontium: metastatic bone carcinoma, cachexia, postmenopausal osteoporosis and hepatic cholestasis. Parameters measured were as follows: mean serum levels of strontium and calcium and strontium:calcium ratio in serum.
GLP compliance:
not specified

Test material

Constituent 1
Reference substance name:
strontium gluconate
IUPAC Name:
strontium gluconate
Test material form:
not specified
Details on test material:
- Name of test material (as cited in study report): strontium gluconate

Method

Type of population:
general
Ethical approval:
not specified
Details on study design:
The clinical studies began by determining strontium and calcium levels in 100 subjects who were receiving a regular diet that supplied approximately 1 g of calcium and 1 to 2 mg of strontium a day. Then, 0.1 to 1.5 g/d of strontium gluconate (183 to 274 mg strontium) were administered for periods of at least 3 months to 50 of these patients with various conditions that might be affected by stable strontium: metastatic bone carcinoma, cachexia, postmenopausal osteoporosis and hepatic cholestasis. Parameters measured were as follows: mean serum levels of strontium and calcium and strontium:calcium ratio in serum.
Exposure assessment:
not specified
Details on exposure:
no data
Statistical methods:
mean ± SD

Results and discussion

Results:
The mean serum levels of strontium and calcium and strontium:calcium ratio in serum of the 100 subjects taking a normal diet were as follows:
strontium: 0.0053 ± 0.0039 mg/dL
calcium: 9.432 ± 0.55 mg/dL
strontium:calcium ratio: 1:2247

The mean level of strontium in the serum of the 50 patients receiving 0.1 to 1.5 g/d strontium gluconate increased, while the calcium level did not change significantly as can be seen below.
strontium: 0.5128 ± 0.198 mg/dL
calcium: 9.449 ± 0.96 mg/dL
strontium:calcium ratio: 1:18
Furthermore, no side effects or toxic reactions were oberved, and 73 % of the patients gained an average of 2 kg of body weight over 2 to 3 months. Subjective feelings of improvement, which are impossible to evaluate, particularly in cancer patients, were frequently reported. In patients with metastatic bone cancer arising from a primary lesion in the breast or prostate, roentgenographic studies showed mineralization of metastatic lesions. Also a sclerotic halo occurred around some of the osteolytic metastatic lesions in the pelvis.
Confounding factors:
no data
Strengths and weaknesses:
no data

Any other information on results incl. tables

ADDITIONAL FINDINGS:

A single oral dose of 0.5 g of strontium gluconate administered to a fasting subject resulted in a marked increase in the serum strontium concentration, with peak being reached in 4 hours; the level decreased rapidly in the next 72 hours, and then gradually over a 4 -week period. The level of calcium in the serum of this patient was 9.7 mg/dL before the strontium was given and 9.4 mg/dL 72 hours later.

Applicant's summary and conclusion

Conclusions:
According to the author, in patients receiving 1 to 1.5 g/d of strontium gluconate, a sustained increase in the serum level of strontium produced a 100-fold increase in the strontium:calcium ratio. Furthermore, an increase in density that corresponded to the deposition of stable strontium was observed in areas of bone lesions due to metastatic cancer in patients receiving stable strontium supplementation.