OSTEOPOROSIS: EPIDEMIOLOGY AND DIAGNOSIS

Dilek Gogas Yavuz,MD

Marmara University School of Medicine Section of Endocrinology and Metabolism

Istanbul ,Turkey

Endo Bridge 2013

Silent disease until complicated by fractures

Osteoporosis: silent epidemic

385 pts with fragility fractures Have you ever heard of osteoporosis?

NO:20% YES:80% Do you think that the fracture you have experienced could be due to fragility of your bones?

NO:73 % YES:27 %

Chavalley et al. Osteoporosis Int 2002;13:450

Definition of osteoporosis

A skeletal disorder characterized by

Compromised bone strength

An increased risk of fracture

NIH Consensus Development Conference, March 2000

Bone strength =bone density+ bone quality

normal osteoporosis

Low bone mass and microarchitectural deterioration

• Worldwide, osteoporosis causes more than 8.9 million fractures annually

• Osteoporosis affects an estimated 75 million people in

Europe, USA and Japan, 2.2 million in Australia, 70 million in China

Osteoporosis Is a Serious Public Health Problem

Every 3 second an osteoporotic fracture occcur

only 10 to 20% are diagnosed and treated

Prevalance of osteoporosis in men and women by gender-spesific scores

Schuit et al. Bone 2004;34:195

Osteoporosis is estimated to affect 200 million women worldwide

approximately one-tenth of women aged 60, one-fifth of women aged 70, two-fifths of women aged 80 and two-thirds of women aged 90

Over 50% of women and 30-45% of men over age 50 have osteopenia/osteoporosis

Men over age 60 has 25% risk osteoporotic fracture

70% over age 80 have osteoporosis

Prevalance of Osteoporosis

At age 50 lifetime risk of

fracture is

1:2 women 1:5 men

Osteoporotic Fractures in Women: Comparison with Other Diseases

Riggs BL, Melton LJ. Bone 1995 Heart and Stroke Facts, 1996, American Heart Association Cancer Facts & Figures, 1996, American Cancer Society

1 500 000*

0

500

1000

1500

2000

Osteoporotic Fractures

*annual incidence all ages † annual estimate women 29+ ‡annual estimate women 30+ •1996 new cases, all ages

513 000†

228 000‡ 184 300•

750 000 vertebral

250 000 other sites

250 000 forearm

250 000 hip

Heart Attack

Stroke Breast Cancer

An

nu

al i

nci

de

nce

x 1

00

0

Risk of osteoporotic fracture in 1 year is greater than combined risk of heart attack, stroke, and

breast cancer.

Hip fracture incidence alone exceeds that of breast cancer.

Cooper C, Melton LJ. Trends Endocrinol Metab. 1992;3:224–229.

Osteoporotic Fractures in Men and Women

4,000

3,000

2,000

1,000

35–39 > 85 > 85

Age Group, yr

Inci

den

ce/1

00

,00

0 P

erso

n-Y

ear

Men Women

Hip

Hip

Vertebrae Vertebrae

Colles’ Colles’

35–39

As with women, hip fractures in men increase dramatically with age

Distribution of Fractures

Consequences of fractures

• Death 10%-20% inrease in mortality with hip fractures

• Disability hip fractures 20% of patients require long-term nursing home care 60% of patients fail to return to prefracture level of function vertabral fractures chronic back pain,kyphosis,height loss, impaired pulmonary function

• Reduced quality of life

• Loss of independence

Clinician’s Guide To The Prevention And Treatment Of Osteoporosis US Department Of Health And Human Sciences

Diagnosis of Osteoporosis

• Based on T score (T Score : standart deviation by which the

individual’s BMD differs from the mean value expected in young healthy individuals)

• Operational definition of osteoporosis: BMD -2.5 SD or

more below the Young female adult mean

• Reference technique :DXA

• Reference site: femoral neck

• Applies to men and to women

Osteoporosis international 2013;24:23-57

WHO criteria for diagnosis of osteoporosis

T score

normal -1.0 and above

osteopenia -1.0 and -2.5

osteoporosis -2.5 and below

Severe (established) osteoporosis

-2.5 and below ,plus one

or more osteoporotic fracture(s)

T-score : Difference expressed as standard deviation compared to young reference population

Kanis et al. J Bone Mineral Res 1994;9:1137

WHO classification with a T-score cannot be applied to:

• premenopausal women • men under age 50 • children

Z score

Low Z-score (less than -2.0) has been suggested by some to increase likelihood of secondary osteoporosis

Who Should Have a Bone Density Test?

Women age 65 and older and men age 70 and older

Younger postmenopausal women and men ages 50–69 with clinical risk factors

Adults who have a fracture after age 50

Adults with a condition (e.g., rheumatoid arthritis) or taking a medication (e.g., glucocorticoids) associated with low bone mass or bone loss

1. Sweet MG, et al. Am Fam Physician. 2009;79(3):193-200. 2. National Osteoporosis Foundation. Clinician’s Guide to Prevention and Treatment of Osteoporosis. www.nof.org. Accessed February 2013.

BMD measurements to predict future fracture risk has a high specificity but a low sensitivity

Most women with hip fractures do not have a T score < -2.5

Wainwright et al JCEM 2005;90:2787

BMD and fracture risk

• The fracture risk varies markedly in different countries ,but T-score varies by a small amount

• Any given T-score to fracture risk

in women from any one country Depends on age • Fracture risk depends of clinical

risk factors

10 –year probability of hip fracture in women according to age and T-score for femoral neck BMD

Osteoporosis int 2013,24:23-57

BMD alone is less optimal as an intervantion

For any BMD, fracture risk higher in the elderly than in the young

Clinical Risk Factors that Affect Fracture Risk

Fractures and weight

Compston JE et al. Am J Med 2011;124:1043

Fracture risk assessment Risk engines

• Garvan fracture risk calculator

• Q fracture

• FRAX

Relative fracture risk BMD 10-year absolute fracture risk Risk Engines

FRAX

• Computer -based algorithm (http://www.shef.ac.uk/FRAX) • Objective: To estimate fracture risk in order to help with

treatment decisions

• Rationale: BMD+CRFs predict fracture risk better than either alone

• Calculates the 10 year probability of a major fracture (hip,

clinical spine,humerus,wrist) and 10-year probability of hip fracture

• designed only for postmenopausal women and men over

the age of 40 who have not previously received bone-protective therapy

Categorization Based on 10-year Fracture Risk

Absolute fracture risk in 10 years:

low: <10%

moderate: 10-20%

high: >20%

Limitations of FRAX™ WHO Fracture Probability Tool

Not valid in patients on treatment

Only hip BMD is considered

Risk is “yes/no” – there is no consideration of “dose” (e.g., fractures, glucocorticoids, smoking, alcohol)

Not all risk factors are included (e.g., falls)

“Major osteoporotic fracture” is not the same as all osteoporotic fractures

Clinical judgment is required

Watts NB, et al. J Bone Miner Res 2009;24:975-979.

Ostoeporosis is a serios health problem

Osteoporotic fractures are expected to rise

Lack of awareness

Risk assesment

Prevenion of fractures

Thank you