Osteoporosis

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• Services- Osteoporosis
• Criteria for referral for Bone Density measurement
• Direct access Bone Density referral
• Evidence Based Medicine: Osteoporosis
• Diet for Osteporosis - Calcium rich foods
• Education - Osteporosis
• Patient Information - Osteoporosis
  

Definition

A disease characterised by low bone mass and microarchetectural deterioration of bone tissue, leading to an enhanced bone fragility and a consequent increase in fracture risk. (WHO 1994)

By the age of 65 1 in 3 women and 1 in 12 men will have developed osteoporosis.

Estimates of the total cost to the nation of osteoporosis £750 million (1994)

The most common reason for people to come to attention for osteoporosis is following fracture especially of the wrist (Colles) or Hip. If considering osteoporosis arrange Bone Densitometry

Criteria for referral for Bone Density measurement

1. Oestrogen deficient women
   - premature menopause (<45 years of age)
   - premature ovarian failure
   -hysterectomy under the age of 40. Hysterectomy may advance the menopause by several years and osteoporosis can occur within 2 years of operation in a quarter of patients.
   - prolonged amenorrhoea (>6 months - anorexia nervosa, female athletes, hyperprolactinaemia).
   Many of these women should be started on HRT / Oestrogen without BMD measurement. BMD measurement should also be considered in these women if they cannot have HRT / Oestrogen because of
   1. significant "thromboembolic disease"
   2. familial hyperlipidaemia
   3. breast carcinoma in patient or first degree relative
   4. significant hypertension
   5. intolerant of HRT/Oestrogen therapy
2. Radiological evidence of vertebral deformity or osteopoenia.
3. Fractures after minor injury.
   Note: Patients who have had one osteoporotic fracture are at an increased risk of a second (60% of women with one vertebral fracture will fracture a second vertebra in three years).
4. long term steroid use.
   Definition: > 7.5 mg predinisolone daily for six months or equivalent.
5. Patients with conditions known to accelerate osteoporosis.
   - Hyperthyroidism
   - Hyperparathyroidism
   - Malabosorption syndromes
   - Hypogonadism
   
6. Men suspected of osteoporosis
   Note: 1/3rd of men will have a secondary cause.
   
7. Women who have complied with two years of HRT therapy, where a bone density measurement will influence the decision to continue treatment.
   
8. Other factors in assessment of risk of osteoporosis.
   
   • Family history of osteoporosis
     
   • Alcohol misuse
     
   • Smoking
     
   • Dietary calcium deficiency.
     Note: There are no clinical features that predict osteoporosis. Bone density, measurement of the spine and hip remain the gold standard by which osteoporosis can be defined. (Position statement of the National Osteoporosis Society June 1998.)
     Forearm x-ray absorptiometry and ultrasound assessment of the heal DO NOT replace the gold standard of spine and hip DEXA scanning. They can indicate which patients require further assessment.
     

When to refer

1. Unexpectedly low bone density, especially if premenopausal.
2. Male osteoporosis - 1/3 of patients have secondary osteoporosis.
3. Unable to tolerate first line management.
4. Secondary osteoporosis.
5. Falling bone mineral density on rescan.
   

Investigations

For all C type scans (see below)

• FBC, PV
• Biochemical profile (P5)
• Protein electrophoresis
• Thyroid function
  (Men only - FSH/LH/Testosterone)
• Antigliadin anti endomysal antibodies to suggest Coeliac disease
  

Further testing can be required to elucidate secondary causes and these will be arranged in Rheumatology outpatients.

Bone Mineral density Interpretation

This will depend on the result of the bone density scan. Current WHO recommendations rely on the T score which compares the individuals bone density scan to the population norm for peak bone mass. This has been shown to be the best predictor of fracture risk. The lowest score is used from the sites L1-4 Femoral neck or Total Hip score

Type A scan: T score between 0 and +2.5

Little chance of osteoporosis - reassure the patient.

Type B scan: T between 0 and -2.5

Consider treatment if there are significant additional risk factors see Criteria for referral for Bone Density measurement

Type C scan: T >/= -2.5

Requires treatment

Management - Women

All individuals need advice about weight bearing exercise, alcohol consumption and the need to stop smoking.

Step 1 HRT is usually first choice and can be started on HRT / Oestrogen without BMD measurement.
However HRT should be avoided if there is

1. significant "thromboembolic disease" - 2 or more DVT's or PE's or a patient known to have Antiphospholipid antibody syndrome (Hughes Syndrome)
2. familial hyperlipidaemia
3. breast carcinoma in patient or first degree relative
4. significant hypertension
5. intolerant of HRT / Oestrogen therapy

Current advice is that HRT should be continued for 10 years and then an alternative found. There is research to suggest the risk of breast cancer increases by 6 cases from 36 -42 per 1000 individuals per year

Step 2 SERM therapy
Raloxifene only member of this group (Selective oEstrogen Receptor Modulator) and has been shown to reduce the risk of fracture.
May reduce the risk of breast cancer.
Major side effect an increase in prevalence of host flushes (13-15% of women will get flushes on commencement of treatment).

Length of use: No evidence to say how long to continue this treatment perhaps again for 10 years

Step 3 Bisphophonates (Didronel PMO or Alendronate)

Didronel may be better tolerated. May use different calcium supplement as Calcit not well tolerated but keep to 2 weeks of Didronel plain 400mg away from food every 3 months with another calcium supplement between courses.
There is no need to stop treatment after 3 years
Fosomax must be taken in the morning after rising with water. No food should be taken for a further 30 minutes

Step 4 Calcium and Vitamin D (need 1500mg calcium and 800 iu of Vit D a day).

Each tablet of Calceous provides 500 mg Ca & 400iu Vit D or Calcichew D3 forte provides 500mg Ca & 400iu Vit D.
Everyone over 80 should receive this
Switch from Bisphosphonates to calcium after 80 years of age
Patients with B scans who do NOT have any additional risk factros should be considered for this treatment irrespective of age

Management - Men

In 1/3rd of men a secondary cause of osteoporosis can be found, often alcohol misuse
Treat underlying cause
Bisphosphonates are usually the first step
If marked hypogonadism (testosterone Normal range 9 to 40 nmol/l) consider referral

Rescans

There is currently much debate about the value of rescans. If the patient is clearly osteoporotic and on effective treatment, there may be little advantage in rescanning.
There is research which suggests that BMD measurement following treatment is NOT a good predictor of subsequent fracture. Treatment may improve Quality more than Quantity of bone - BMD measure Quantity only

Question: How would treatment be changed if the BMD is not stable?
It is probably sensible to rescan patients at 3 - 5 years to ensure that the BMD is stable or improving. This may allay also some patients fears. Remember BMD falls by 3% per year normally.

Stable BMD: T <= 1.0 SD> Reassure
T <= 1.0> continue HRT/BSP

Falling BMD: Combination of therapy eg HRT and BSP's or BSP and Vitamin D may be better than single treatment.

Key

• BMD = bone mineral density
• BSP = bisphosphonate - Didronel PMO/Alendronate (Fosomax)
  

Special Points

If the BMD of an isolated vertebra is markedly different from the mean then consider osteo-blastic/clastic neoplasm or Pagets disease.

Service provided by Rheumatology Outpatients.

First appointment:

1. Clinical History and examination to ascertain risk factors and the impact of the disease
2. Interpretation of DEXA scan.
3. Assessment of available investigations: Identification and completion of appropriate secondary investigations
4. Recommendations of appropriate treatment: including assessment for inpatient Pamidronate infusion to stabalise acute vertebral fractures
5. Patients will be educated in all aspects of osteoporosis management .
6. The Rheumatology multidisciplinary team is available for full assessment as required.

Follow up appointment:

In straightforward cases, there will be no need for further follow up. If secondary investigations have been made or the clinical picture is complicated, follow up appointments will be made as the discretion of the consultant.

Document Information
Expiry Date: 11/04/04
Author: Kennedy Tom Dr
Organisation: Arrowe Park Hospital