Osteoporosis

There is a normal decline in bone mass after the age of 40 in both sexes (2% loss/year); women at much greater risk due to lower bone density prior to the age of 40; post-menopausal (PM) osteoporosis is the most common form; 1 in 4 PM women has osteoporosis (OP).

The diagnostic summary of osteoporosis is as follows:

• • usually asymptomatic until severe backache (often called a silent killer)
• • most common in postmenopausal white women
• • spontaneous fractures of the hip and vertebrae
• • decrease in height
• • demineralisation of spine and pelvis as confirmed by x-ray techniques

The major risk factors for osteoporosis in women are as follows:

• • Postmenopausal
• • White or Asian
• • Premature menopause
• • Positive family history
• • Short stature and small bones
• • Leanness
• • Low calcium intake
• • Inactivity
• • Nulliparty
• • Gastric or small bowel resection
• • Long-term glucocorticosteroid therapy
• • Long-term use of anticonvulsants
• • Hyperparathyroidism
• • Hyperthyroidism
• • Smoking
• • Heavy alcohol use

The entire skeleton is involved, but bone loss is greatest from the spine, hips, and ribs – weight-bearing causes susceptibility to pain, deformity or fracture.

Aetiology of osteoporosis

Involves mineral (inorganic) and non-mineral (organic protein matrix) components of bone; lack of dietary calcium in adult causes osteomalacia (‘softening of bone’); in osteomalacia, only Ca is deficient in bone; in osteoporosis, there is a lack of Ca, other minerals plus decreased non-mineral framework (organic matrix); Ca and vitamin D are the most important nutritional factors; hormones critical – incorporation of Ca into bone is dependent upon oestrogen.

• Gastric acid: Ca absorption depends on being iodised/solubilised by stomach acid; 40% of postmenopausal women are hypochlorhydric; patients with insufficient stomach HCL absorb only 4% of Ca as calcium carbonate – a person with normal HCL absorbs 22%; hypochlorhydic patients need Ca in soluble/ionised state (citrate lactate, gluconate); 45% of Ca is absorbed from calcium citrate in patients with hypochlorhydria.

• Vitamin D: stimulates Ca absorption; synthesised by action of sunlight on 7-dehydrocholesterol in skin – considered more a hormone than a vitamin; sunlight converts 7-dehydrocholesterol into vitamin D3 (cholecalciferol); liver converts D3 into 25-hydroxycholecalciferol (25-(OH)D3) (five times more potent than D3), which is converted by kidneys to 1,25-dihydroxycholecalciferol (1,25-(OH)2D3) (10 times more potent than D3); liver or kidney disorders impair conversion of D3; many patients with osteoporosis have high 25-OH-D3 but low 1,25-(OH)2D3 – suggests impaired kidney conversion; boron theorised to help this conversion.

• Hormonal factors: blood Ca level strictly circumscribed; Ca decrease triggers parathyroid hormone (PTH) release and decreases secretion of calcitonin by thyroid and parathyroids; Ca increase decreases secretion of PTH and increases calcitonin; PTH increases serum Ca by activating osteoclast catabolism of bone, decreasing kidney Ca excretion, increasing kidney conversion of 25-(OH)D3 to 1,25-(OH)2D3, and increasing intestinal Ca absorption; oestrogen deficiency makes osteoclasts more sensitive to PTH, increasing bone breakdown.

Diagnostic Methods of osteoporosis

Best diagnosed by bone sonometry and bone densitometry –  dual energy X-ray absorptiometry (DEXA) – measures hip and lumbar spine densities; for high-risk women, get baseline bone density and then monitor bone loss by bone sonometry (ultrasound) or  urine tests for bone breakdown products (cross-linked N-telopeptide of type 1 collagen or deoxypridium); urine tests give quicker feedback than DEXA (up to 2 years to detect therapeutic response); reducing urinary markers of bone breakdown over a 2-year period increases bone density measurements.

Bone sonometry screening is used to measure the condition of the bones, especially for the risk of fracture (osteoporosis). Bone sonometry has advantages over the tradition X-ray methods for the assessment of bone. ICIM bone sonometry does not use any radiation thus there are no risks associated with bone sonometry screening. It is a quick and safe method of measuring bone density. Additionally, while X-ray methods measure the density of bone, sonometry provides information relating to the strength of the bone (structure, elasticity) which is important for determining fracture risk. For more information on bone sonometry please go to http://www.icim.ie/diagnostics.htm.

Therapeutic considerations

Primary goals:

1.       Preserve mineral mass,
2.      Prevent loss of protein matrix and other structural components,
3.      Assure optimal repair to remodel damaged bone.

Hormone replacement therapy: benefits of HRT outweigh risks in women susceptible to OP or already suffering major bone loss; prefer oestrogen-progesterone combinations to oestrogen alone; exceptions are women at high risk for breast cancer or suffering diseases aggravated by oestrogen (breast cancer, activate liver diseases, certain cardiovascular diseases) – use progesterone alone.

Lifestyle factors: coffee, alcohol, and smoking cause negative Ca balance and are linked to increased risk of OP; regular exercise reduces risk; exercise is most critical for maintaining healthy bones – physical fitness is the major determinant of bone density;  1 hour of moderate activity three times/week prevents bone loss and increases bone mass in PM women.

General dietary factors

Vegetarian diet (lacto-ovo and vegan) is linked to lower risk of OP; bone mass in vegetarians and omnivores differs only after fifth decade – decreased OP in vegetarians is not due to increased initial bone mass, but decreased bone loss; high-protein or high-phosphate diet is linked to increased urinary Ca excretion; refined sugar increases urinary Ca excretion.

• Soft drinks: major factor for OP – high phosphates and no Ca, leading to lower blood Ca and high blood phosphate; consumption in children is a risk factor for impaired calcification of growing bones; strong correlation between bone mineral density and risk of OP; significant inverse correlation between serum Ca and number of bottles of soft drink consumed per week.

• Green leafy vegetables: green leafy vegetables protect against OP – sources of Ca, vitamin K1, and boron:

- vitamin K1 converts inactive osteocalcin to active form; osteocalcin is a major non-collagen protein in bone that anchors Ca into protein matrix; vitamin K deficits impair bone mineralization due to inadequate osteocalcin; low blood K1 found in patients with OP-linked fractures; severity of fracture is strongly correlated with circulating vitamin K; the lower the level of circulating vitamin K, the lower the bone density; sources are dark green leafy vegetables, broccoli, lettuce, cabbage, spinach, green tea; minerals (Ca, boron) – protective effect

- supplemental boron in PM women reduces urinary Ca excretion and increases 17-beta-estradiol; boron activates certain hormones, including oestrogen and vitamin D; boron required for converting vitamin D to 1,25-(OH)2D3 within kidney; fruits and vegetables are main dietary sources of boron.

Nutritional supplements

• Calcium: supplements reduce bone loss in PM women; Ca alone does not completely halt Ca loss, but slows rate by 30-50%; protects against hip fractures; with exercise and dietary recommendations, Ca is part of effective treatment for most women; Ca supplements alone significantly prevent bone loss; greater benefit using more absorbable forms (citrate or bound to other Krebs cycle intermediates); continued Ca supplementation produces sustained reduction in rate of loss of total bone mineral density in healthy PM women and reduces incidence of bone fractures; improves bone density in perimenopausal women; beware of lead contamination in some Ca supplements; prefer products lab-tested for purity and potency; avoid natural oyster shell Ca, dolomite, and bone meal products unless manufacturer can document purity; calcium hydroxyapatite (purified bone meal) tested at 20% absorption compared with 30% for carbonate or citrate.

• Vitamin D: vitamin D3 alone may reduce annual rate of hip fracture from 1.3 to 0.5% - nearly a 60% reduction; increases hip bone density; combined with Ca produces slightly better results; vitamin D can be helpful in elderly people living in nursing homes, people living further away from equator, and those who do not regularly get outside.

• Magnesium: may be as important as Ca in preventing and treating OP; women with osteoporosis have lower bone Mg content and other indicators of Mg deficiency than people without OP; enzyme responsible for conversion of 25-(OH)D3 to 1,25-(OH)2D3 is Mg-dependent; Mg mediates PTH and calcitonin secretion; slightly improves bone density in PM women.

• Vitamin B6, folic acid, and vitamin B12: low levels of these nutrients are common in elderly; important in conversion of amino acid methionine to cycteine; deficiency or defect in enzymes responsible for conversion causes increase in homocysteine – implicated in atherosclerosis and osteoporosis; hyperhomocysteinemia demonstrated in PM women; may contribute to osteoporosis by interfering with collagen cross-linking, leading to defective bone matrix; folic acid reduces homocysteine in PM women even though none were deficient in folic acid according to standard folic acid lab criteria; vitamin B6 and B12 are also necessary in metabolism of homocysteine; combinations of these vitamins will produce better results than either one of them alone.

• Silicon: necessary for cross-linking collagen strands, contributing to strength and integrity of connective tissue matrix of bone; silicon concentrations increased at calcification sites in growing bone; recalcification in bone remodelling may depend on silicon.

• Fluoride: fluoride administration is a popular therapy, but validity still in question; fluoride’s predominant effects; stimulating osteoblasts and positive Ca balance; incorporated into crystalline structure of bone as fluoroapatite, but bone matrix is poorly formed and weak; long-term excessive exposure causes bone fragility.

• Phytoestrogens: may be suitable alternatives to oestrogens to prevent OP in menopausal women; ipriflavone is a semi-synthetic isoflavonoid similar to soy isoflavonoids that increases bone density by 2 and 5.8% after 6 to 12 months, respectively, in women with OP; long-term studies are documenting safety and efficiency of ipriflavone; naturally occurring isoflavonoids (genistein and daidzein in soy) may exert similar benefits; soy isoflavonoid protection against breast cancer alone warrants regular consumption of soy foods; mechanism of action may be enhancement of calcitonin effects of Ca metabolism as ipriflavone exerts no oestrogen-like symptoms.

Therapeutic approach to osteopososis

The approach ICIM Medics takes is as follows. Osteoporosis may be preventable is appropriate dietary and lifestyle measures are followed; bone is dynamic, living tissue that requires constant supply of high quality nutrition and regular stimulation (exercise); primary goal is prevention; in severe cases of OP, use natural measures in conjunction with appropriate medical care, including pharmaceuticals.

• Diet: avoid items promoting excretion – salt, sugar, protein, soft drinks.
• Supplements

• - high-potency multiple vitamin-mineral formula
• - calcium
• - magnesium
• - vitamin D
• - boron

For more information on this topic please call ICIM Medics on +353 45 844 819 or email us at info@icim.ie

Tags: Joints