BACK PAIN AND LUMBAR STENOSIS IN OLDER ADULTS

BACK PAIN AND LUMBAR STENOSIS IN OLDER ADULTS

RESEARCH GROUP University of Pittsburgh Shervadalonna Brown, MD Jane A. Cauley, Dr. PH William F. Donaldson, MD James D. Kang, MD Douglas Musgrave, MD Terence Starz, MD Mark Chirumbole, BS Anthony De. Litto, Ph. D Julie Fritz, Ph. D Lewis H. Kuller, MD Molly T. Vogt, Ph. D University of California at San Francisco Michael Nevitt, Ph. D Ria San Valentin, MD Lisa Palermo, MS Georgetown University William C. Lauerman, MD Dartmouth Medical Center Brett Hanscom, MS James Weinstein, DO Washington University, St Louis David Rubin, MD

INTRODUCTION 80% of US population experience one or more episodes of low back pain during lifetime. One of leading causes for physician office visits and for filing disability claims. During last 3 decades disability claim rate has increased 13 fold. Annual medical costs related to back pain are estimated to be $8 - $18 billion.

INTRODUCTION Low back pain (LBP) affects 90% of individuals. Initial episode of LBP Persistent LBP after 4 -6 weeks-10% Recovery in 4 -6 weeks 90% Recurrence in one year- 30% LBP impacts quality of life & health care expenditures.

INTRODUCTION National guidelines have recommended the use of analgesics as the primary pharmacologic treatment for LBP. The choice of analgesic agent has major implications for health care costs.

UPMC Health Plan (Commercial) • 17, 228 (14. 8% of total) health plan members had at least one claim for service (pharmacy, inpatient, outpatient, laboratory, and physical /occupational therapy) for LBP management. Total cost = $6, 419, 696 • 9, 566 (56% of members with LBP claims) had pharmacy claims for narcotics, NSAID’s, Cox 2’s or other analgesics. Total cost = $1, 403, 837

UPMC-HP Member Resource Utilization for LBP % of members Narcotics X-rays NSAIDs MRI PT/OT Cox 2 s analgesics

Narcotic costs for UPMC-HP members with LBP or cancer $ LBP 48% of total narcotic costs attributed to members with LBP, 21% to members with cancer Cancer

Utilization Pattern of Pain Medications among LBP patients in UPMC-HP Narcotics+ other analgesics Narcotics alone Narcotics+nonselective NSAID analgesic alone Cox 2 alone NSAIDs alone

INTRODUCTION Back pain in adult patients linked with: • lifestyle factors (smoking, obesity, physical activity, education) • anatomic abnormalities of lumbar spine Back pain in the elderly related to: • degenerative changes due to aging • lifestyle less important

Back pain in older persons Increasing age is associated with an increase in musculoskeletal symptoms In the US back pain is the 3 rd most frequent symptom reported to MDs by persons 75+ years 17% of back problem visits occur in those aged 65+ years BUT neither prevalence nor health burden is known

Prevalence of back pain in older persons Bressler, et al. Spine 1999

Prevalence of back pain in older persons Prevalence seems to decrease a little with age Women usually report a higher prevalence than men A major problem is the definition of back pain “no gold standard” No studies of the validity/reliability of dx orthopaedic testing procedures, no validity studies of clinical or self report of location of back pain Bressler, et al. Spine 1999

Patient factors contributing to the variability of prevalence of back pain in older persons • cognitive impairment • depression • decreased pain perception • increased pain tolerance • comorbid conditions • decreased physical activity • resignation to aging effects • selective participation in studies Overall seems likely that back pain is often under-reported

Relationship between history of CVD at baseline and back problems at the 3 rd clinic visit Age-adj OR (95% CI) _______________________ Back pn since 1 st clin vis none mild/mod severe 1. 0 1. 3 (1. 0, 1. 6) 2. 6 (1. 7, 4. 0) One + days of lim act due to back pain 2. 3 (1. 6, 2. 3) One + days in bed due to back pain 1. 2 (0. 6, 2. 3) Vogt, et al, Spine 1997

Odds ratio for back pain at baseline in SOF women (65+ yrs) by estrogen usage * * * Odds ratio * Visit Musgrave, et al. Spine 2001

Causes of back pain in older patients Acute (< four weeks) lumbar strain/sprain osteoporotic fracture, vertebral or pelvic abdominal aortic aneurysm Subacute/Chronic (> four weeks) degenerative disc and joint disease malignancy fibromyalgia polymyalgia rheumatica Parkinson’s disease

Predictors of chronicity of low back pain in adults (n=1246) Carey, et al, Spine 2000

Primary location of pain 1. Lower back pain alone 2. Pain radiating into buttocks and leg * upper anterior thigh/groin * lateral hip * below knee Malignant, infectious or visceral pain is constant whatever position of body. Mechanical, myofascial or degenerative pain varies by body position usually lessens when person is supine

Radicular pain spinal nerve entrapment by disc herniation or spinal stenosis pain in leg, paresthesia, weakness

Causes of leg pain in older patients True radicular pain lumbar stenosis lumbar disc herniation Pseudosciatica trochanteric bursitis osteoarthritis of the hip diabetic neuropathy

ANATOMY Normal human spine is lordotic in the lumbar region. During typical movements upper lumbar vertebrae - posterior shear lower lumbar vertebrae - anterior shear Stability maintained by facet joints, intervertebral discs, ligaments, related muscle groups

PATHOLOGY Degenerative changes in the lumbar spine disc degeneration vertebral compression deformities ligamentous laxity deterioration of facet joint cartilage May cause instability and subluxation of one vertebra on another (degenerative spondylolisthesis)

Anterolisthesis at L 4 -L 5

PATHOLOGY Backward slippage (retrolisthesis) is generally believed to be asymptomatic and of little clinical significance. Forward slippage (anterolisthesis) may result in narrowing of vertebral canal and neural foramina (spinal stenosis) leading to development of chronic back pain (with or without leg pain). Compression of L 5 spinal nerve may be involved.

PATHOLOGY When LS joint is particularly stable, L 4 and L 5 are more vulnerable to stress forces. If degenerative changes have occurred, anterolisthesis at L 4 is more likely. Clinical symptoms associated with anterior subluxation at L 4 -L 5 at L 3 -L 4 80% 10 -20%

PATHOLOGY Spinal stenosis symptoms: back pain progressing to leg pain functional independence deteriorates reduced ability to walk reduced ability to carry out ADLs Symptoms often episodic, no natural resolution over time

EPIDEMIOLOGY Several clinical and cadaveric studies suggest that anterolisthesis is 5 times more common in women vs men 2 -4 times more common in blacks than whites 4 times more prevalent in diabetics 3 times more common in oophorectomized women compared to controls

Prevalence of lumbar listhesis (L 3 -S 1) in elderly white women (SOF) listhesis defined as subluxation > 3 mm p for trend = 0. 027 p for trend = 0. 75

CLINICAL RELATIONSHIPS Relationship between radiographic abnormalities and spinal symptoms is unclear. People with no back pain show disc abnormalities (64%), stenosis (7%) and anterolisthesis (7%) (Boden, JBJS 1990, Jensen NEJM 1994 ). Not known whether people with sub-clinical disease later develop symptoms.

Veteran’s Health Study % of cohort n= 428 men Selim, et al. Spine 1998

Veteran’s Health Study Selim, et al. Spine 1998

SF-36 scores for men with LBP enrolled in the Veteran’s Health Study Score p for trend <0. 05 for all domains Selim, et al. Spine 1998

Distribution of lower back and leg pain symptoms w/in last month among white WHI women aged 50 years and older n=295 n=47 n=182 n=49 Vogt et al. J Gerontol 2002

SF-36 scores for white women enrolled in WHI (adjusted for age and BMI) Score Vogt et al. J Gerontol 2002

Relationship of race to prevalence and use of health care resources for LBP Random digit dialing + structured interview 4, 437 households in NC 8067 individuals Carey, et al, Spine 1996

Relationship of race to prevalence and use of health care resources for LBP Cohort study, random group of health care providers Carey, et al, 2000

Elderly African American women (SOF) reporting back pain during previous four weeks N=470 severe LBP moderate LBP no LBP mild LBP

Back/leg symptoms in women aged 65 years and older during month prior to clinic visit (white women enrolled in WHISTEN, black women enrolled in SLIP)

Prevalence of lumbar listhesis (L 3 -S 1) in black elderly women by age listhesis defined as subluxation > 3 mm p for trend = 0. 095 p for trend = 0. 207

% prevalence of listhesis among women 65 years and older Vogt, et al, The Spine J 2002

Effect of back pain & leg pain on daily life of black women during previous month Odds ratio expressed as age-adj odds ratio using back pain only as the reference - all p<0. 001 Vogt, et al, The Spine J 2002

PREVENTION Because most people experience LBP during their lifetime, the distinction between primary and secondary prevention is blurred. • which interventions can prevent occurrence of LBP? • which interventions can prevent development of chronic LBP?

PREVENTION Evidence-based medicine categories Level A - strong consistent - multiple RCTs Level B - moderate - one RCT + multiple CCTs Level C - limited - one CCT Level D - no evidence

PREVENTION Lumbar supports Level A - ve • provide support • remind to lift properly • intra-abdom pressure and • intradiscal pressure RCTs negative CCTs positive – reduce incidence of LBP and back injury

PREVENTION Back Schools and Education Level A -ve • provide knowledge about body mechanics, stress, exercise • aim to influence behavior 9 RCTs - most are negative 5 CCTs - positive

PREVENTION Exercises Level A + ve • strengthen back muscles • increase blood supply • improve mood and alter perception of pain 6 RCTs – reduced pain and sick leave

PREVENTION Ergonomics Level D - ve • job related interventions No RCTs or CCTs

PREVENTION Risk Factor Modification Level D - ve • individual (weight, strength, smoking) • biomechanical (lifting, posture) • psychosocial (job control, job dissatisfaction, depression) No RCTs or CCTs

Review of 47 epidemiologic studies concluded that smoking may be a ‘weak risk indicator and not a cause of low back pain’ Le -Bouef-Yde Spine 1999 Smoking may have a systemic effect on the musculoskeletal system - associated with generalized pain. Biological basis unknown - neuroendocrine effect?

SF-36 score Decrement in SF-36 scores (compared to age-sex specific norms) for patients with spinal problems by smoking status Vogt, et al, Spine 2002

PREVENTION Currently only exercise seems to be helpful in prevention of LBP. Consistent evidence – Level A. Linton, van Tulder, Spine 2001

PREVENTION Why the disappointing results? • small studies, low power, short follow-up, variation in intervention, varying outcome • natural course of back pain, hard to define and categorize, multi-factorial causation • single modal programs studied mostly, maybe multi-dimensional approach needed • timing, compliance