Calcium is an important mineral in the body, 99% of which is found in bones and teeth, and the remaining 1% is distributed in blood, nerves and various soft tissues. In bone tissue, calcium ions and phosphorus form hydroxyphosphate lime crystals that settle on the matrix composed of collagen, maintaining the firmness of the bone.
Whether it is primary osteoporosis (including postmenopausal, senile, and idiopathic), or osteoporosis secondary to a variety of other diseases or drugs, calcium supplementation reduces bone loss and is an essential adjunctive treatment. However, in clinical work, calcium supplementation treatment may not be reasonable enough to regulate. Reasonable specification of calcium supplementation, what do you need to pay attention to?
Note 1: Calcium is chosen reasonably
Analysis: Based on the physiological biochemical function and pharmacological effect of calcium elements, the preparation with calcium salts as the main component is called calcium agent. There are many varieties of calcium agents, which can be divided into inorganic calcium and organic calcium acid according to their components. Inorganic calcium mainly includes calcium oxide, calcium carbonate, dibasic calcium phosphate, calcium chloride, calcium hydroxide and so on. Organic calcium acid mainly includes calcium gluconate, calcium lactate, calcium citrate, calcium citrate and so on. The calcium content of inorganic calcium is higher, but most of them have low solubility and great gastrointestinal stimulation; calcium organic acid is generally better solubility, but calcium content is low.
When selecting calcium agents, the characteristics of the population and the combined diseases should be combined. Like what:
1. People who lack stomach acid basically do not absorb inorganic calcium, and the elderly often have reduced gastric acid secretion, so it is recommended that people older than 65 years old and with stomach acid deficiency take organic calcium acid such as calcium citrate, and calcium supplementation in the general population is elected as inorganic calcium with high calcium content such as calcium carbonate;
2. Patients with hypoparathyroidism and chronic renal failure, often combined with hyperphosphatemia, can not choose phosphorus-containing calcium agent (calcium bisphosphate), should choose calcium carbonate, calcium citrate, calcium acetate, both calcium supplementation, can also be used as a phosphorus binder for hyperphosphatemia, to reduce blood phosphorus concentration;
3. Calcium citrate increases intestinal aluminum absorption, and those who take aluminum agents are banned;
4. Calcium gluconate is not suitable for diabetic patients;
5. Calcium acetate is easy to cause blood pressure to rise, and is not suitable for patients with hypertension and cardiac insufficiency.
Long-term use of general calcium, such as calcium carbonate (calcium carbonate), will cause increased blood calcium and urinary calcium concentrations, will increase the risk of urinary tractoxalate calcium crystallization, stone formation, especially in patients with a history of urinary system stones. Calcium citrate has a strong complex of calcium, when increasing the concentration of citric acid, it can be combined with the replacement of calcium oxalate, free calcium ions and calcium phosphate salts, etc., thereby forming a complex that is easily soluble in water, inhibiting the supersaturated state of calcium oxalate supersaturation and crystallization and forming stones. Calcium supplementation in patients with urinary stones is recommended for use of calcium citrate.
Note 2: The dosage and usage are exquisite
Analysis: China Nutrition Society formulated a recommended amount of adult daily calcium intake of 800 mg is the ideal bone peak, maintain bone health of the appropriate dose, if the diet of calcium supply is insufficient optional calcium supplement, for postmenopausal women and the elderly, the recommended daily calcium intake is 1000 mg. The current dietary nutrition survey shows that the average daily calcium obtained by the elderly in China is about 400 mg, so the average daily amount of elemental calcium that postmenopausal women and the elderly should supplement is 500-600 mg (such as calcium carbonate contains 600 mg of elemental calcium per tablet).
After calcium supplementation, it is recommended to test the blood calcium and urine calcium concentration every 3 months, if hypercalcemia occurs, the drug should be discontinued, and the increase in urinary calcium should reduce the calcium dose. Taking calcium, a large dose at a time, is not as good as the absorption rate of taking in batches. May be taken 1 time in the morning and 1 time in the evening, or 3-4 times/day. Commonly used calcium carbonate is better absorbed in an acidic environment, calcium carbonate is taken with food, due to food stimulation so that gastric acid secretion increases, can make the absorption efficiency of calcium increased, if the elderly unconditionally take organic calcium, you can use this method to take calcium carbonate. Organic calcium does not require acid activation and does not have to be taken with food. At the same time, it should be noted that vegetables containing more oxalic acid (spinach, amaranth) reduce the absorption of calcium, and try to avoid the use of calcium.
Note 3: "Golden Partner" is indispensable
Analysis: Vitamin D can promote the absorption of calcium, which is beneficial for bone health, maintaining muscle strength, enhancing the body's balance, reducing falls, and reducing the risk of fractures. Vitamin D deficiency can lead to secondary hyperparathyroidism, increased bone resorption, and thus cause or worsen osteoporosis. While supplementing calcium, vitamin D is indispensable as a "golden partner" and is also an essential treatment.
Although vitamin D is added to some calcium agents, the dose is far from sufficient. When the relevant guidelines in China recommend ordinary vitamin d for the treatment of osteoporosis, the dose can be 800-1200iu/day. Regular vitamin D is converted to active vitamin D to function, so active vitamin D can be used instead of supplementation, including α-calcitriol (0.25-1.0 micrograms daily) or calcitriol (0.25-0.5 micrograms daily).
Osteoporosis secondary to renal failure is due to decreased synthesis of active vitamin d, but calcitriol can only be supplemented because α-calcitriol requires renal activation, and this activating enzyme is reduced in patients with renal failure.
When combining calcium and vitamin D preparations with clinical use, blood calcium and urinary calcium should also be monitored once in 3 months, and the dose should be adjusted as appropriate. Hospitals with the capacity are advised to test serum 25-hydroxyvitamin d levels (reflecting vitamin D nutritional status for better supplementation) at or above 30 ng/ml (75 nmol/l) to reduce the risk of falls and fractures.