Methods

Results

Cohort Definition

SMT Initiation in 2013 of long-term management with SMT, and no OAT for 12 months after initiating SMT

OAT Initiation in 2013 of long-term management with OAT, and no SMT for 12 months after initiating OAT

SMTX Any occurrence of SMT for cLBP in 2013, followed by initiation in 2013 of long-term management with OAT

OATX Any occurrence of OAT for cLBP in 2013, followed by initiation in 2013 of long-term management with SMT

Table 2. Frequency of Adverse Drug Events

The combined cohort OATC was more racially diverse than SMTC Females outnumbered males by approximately 3:1 within all cohorts. With controlling for patient characteristics, health status and propensity score, the adjusted rate of ADE was more than 42 times higher for initial choice of OAT vs. initial choice of SMT (Rate Ratio 42.85, 95% CI 34.16-53.76, p <.0001). .

AcknowledgementsThis research was supported by the National Center for Complementary and Integrative Health (NCCIH) of the National Institutes of Health under award number 1R15AT010035. This project was 100% federally funded. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. We acknowledge Dr. John Lurie for his guidance with this study.

References1. Qaseem, A., T. J. Wilt, R. M. McLean and M. A. Forciea (2017). "Noninvasive Treatments for Acute,

Subacute, and Chronic Low Back Pain: A Clinical Practice Guideline From the American College of Physicians." Ann Intern Med. 166(7): 514-530. doi: 510.7326/M7316-2367. Epub 2017 Feb 7314.

2. Whedon, J. M., A. W. J. Toler, L. A. Kazal, et al. (2020). "Impact of Chiropractic Care on Use of Prescription Opioids in Patients with Spinal Pain." Pain Med 6(5788462).

3. Corcoran, K. L., L. A. Bastian, C. G. Gunderson, et al. (2020). "Association Between Chiropractic Use and Opioid Receipt Among Patients with Spinal Pain: A Systematic Review and Meta-analysis." Pain Med. 21(2): e139-e145. doi: 110.1093/pm/pnz1219.

4. Whedon, J. M., C. M. Goertz, J. D. Lurie and W. B. Stason (2013). "Beyond spinal manipulation: should Medicare expand coverage for chiropractic services? A review and commentary on the challenges for policy makers." J Chiropr Humanit. 20(1): 9-18. doi: 10.1016/j.echu.2013.1007.1001. eCollection 2013 Dec.

Chronic Low Back Pain (cLBP) has a prevalence of approximately 23% and is a cause of disability in 11-12% of the population. Both Opioid Analgesic Therapy (OAT) and Spinal Manipulative Therapy (SMT) are regimens used to treat cLBP, but for long-term care of older adults with cLBP, the safety of either approach is uncertain. The objective of this study was to compare SMT and OAT to determine the impact of SMT on the risk of ADEs.

Introduction & ObjectiveThe present study is the first to examine long-term risk of ADE associated with with SMT vs. OAT among Medicare patients with cLBP. The results suggests that risk of opioid-associated ADE could be reduced if patients with cLBP first consulted a chiropractor. The results support our hypothesis that recipients of OAT have higher rates of ADE as compared with recipients of SMT.

. The frequency of occurrence of an ADE for the OAT cohort was nearly six times higher than for the SMT cohort. Thus, regarding risk at 12 months of any ADE, patients who initially chose SMT as their initial approach to treatment had received care that was measurably safer than those who chose OAT, at least regarding medication safety. Primary utilization of spinal manipulation is congruent with clinical practice guidelines for cLBP and promises better quality and safer care for older US adults with cLBP, a challenging population to manage due to high prevalence of multiple co-morbidities and polypharmacy. Chiropractors should take a history and be aware of the fact that a substantial number of their senior patients are taking opioids and of the risk of ADE that may complicate management. Chiropractors should work closely with a patient's medical physician to ensure that any adverse events are recognized and managed appropriately.

ConclusionsAmong older Medicare beneficiaries who received long-term care for cLBP, for patients who first chose care via OAT, the adjusted rate of experiencing an ADE was significantly higher as compared to those who first chose SMT.

Potential survey participants were identified through analysis of Medicare claims data. Four cohorts of Medicare beneficiaries were assembled according to previous treatment received as evidenced in Medicare claims data as explained below:

We collected data on the demographic characteristics of included patients. Patient age in years at time of cohort accrual was categorized as 65-69, 70-74, 75-79, and 80-84. Sex as a biological variable was collected as male or female.

We analyzed the cumulative frequency at 12 months of ADEs occurring in an outpatient setting, as measured by diagnosis code. We generated descriptive statistics on patient characteristics and on the frequency of outcomes for primary cohorts SMT and OAT, crossover cohorts SMTX and OATX, and combined cohorts SMTC and OATC.

Initial Choice of Spinal Manipulation for Treatment of Chronic Low Back Pain Leads to Reduced Long-term Risk of Adverse Drug Events among Older Medicare Beneficiaries

Bangash M 1; Kizhakkeveettil A1; Whedon J1 ; Haldeman S1

1 Southern California University of Health Sciences, Whittier, CA;

Discussion

Primary Cohorts Crossover Cohorts Combined CohortsSMT OAT SMTX OATX SMTC OATC Total

N 4,998 20,947 1,431 784 6,429 21731 28,160Adverse Drug Event N % N % n % n % n % n % N

Any Adverse Drug Event 45 0.90% 3,832 18.30% 151 10.60% 36 4.60% 196 3.00% 3,868 17.80% 4,064Opioid Poisoning * * 383 1.80% 13 0.90% * * 15 0.20% 385 1.80% 396Non-Opioid Prescription Drug Poisoning * * * * * * * * * * * * *

Salicylates Poisoning * * 12 0.10% * * * * * * 13 0.10% 12Opiate Antagonists Poisoning * * * * * * * * * * * * *Skeletal Muscle Relaxants Poisoning * * * * * * * * * * * * *

Unspecified Drug Poisoning * * 558 2.70% 18 1.30% * * 24 0.40% 560 2.60% 576

Unspecified Adverse Effect 20 0.40% 420 2.00% 20 1.40% * * 40 0.60% 429 2.00% 460

Opioid Dependence or Abuse 17 0.30% 3,003 14.30% 118 8.20% 23 2.90% 135 2.10% 3,026 13.90% 3,161

Cohorts Primary CrossoverCombined

Total N

SMT OAT SMTX OATXSMTC

OATC

N 4,998 20,947 1,431 7846,429 21,731

28,160

Age at accrual (years)

Mean SD Mean SD Mean SD Mean SD Mean SD Mean SD -

73.1 4.8 72.6 4.8 73.1 4.9 72.9 4.7 73.1 4.8 72.6 4.8 -

Age Category (years) n % N % n % n % n % n % -

65-69 1,599 32.0% 7,817 37.3% 461 32.2% 254 32.4% 2,060 32.0% 8,071 37.1% 10,131

70-74 1,721 34.4% 6,787 32.4% 495 34.6% 283 36.1% 2,216 34.5% 7,070 32.5% 9,286

75-79 1,125 22.5% 4,254 20.3% 302 21.1% 172 21.9% 1,427 22.2% 4,426 20.4% 5,853

80-84 553 11.1% 2,089 10.0% 173 12.1% 75 9.6% 726 11.3% 2,164 10.0% 2,890

Sex

Male 1,440 28.8% 5,543 26.5% 355 24.8% 191 24.4% 1,795 27.9% 5,734 26.4% 7,529

Female 3,558 71.2% 15,404 73.5% 1,076 75.2% 593 75.6% 4,634 72.1% 15,997 73.6% 20,631

Table 1. Patient Characteristics

Notes: Cohort Definitions: SMT = patients who initiated SMT in 2013 for long-term management of cLBP, with no concurrent OAT; OAT = patients who initiated OAT in 2013 for long-term management of cLBP, with no concurrent SMT; SMTX = patients with any occurrence of SMT in 2013, followed by initiation in 2013 of OAT for long-term management of cLBP; OATX = patients with any occurrence of OAT in 2013, followed by initiation in 2013 of SMT for long-term management of cLBP; SMTC = combination of SMT and SMTX; OATC = combination of OAT and OATX; n = number of patients; * = data suppressed in accordance with CMS rules

Notes:SMT = patients who initiated SMT in 2013 for long-term management of cLBP, with no concurrent OAT; OAT = patients who initiated OAT in 2013 for long-term management of cLBP, with no concurrent SMT; SMTX = patients with any occurrence of SMT in 2013, followed by initiation in 2013 of OAT for long-term management of cLBP; OATX = patients with any occurrence of OAT in 2013, followed by initiation in 2013 of SMT for long-term management of cLBP; SMTC = combination of primary and crossover cohorts, in which all patients chose SMT as the initial treatment ; OATC = combination of primary and crossover cohorts, in which all patients chose OAT as the initial treatment; n = number of patients; Secondary care encounters = patient visits for primary diagnosis of low back pain, identified by Current Procedural Terminology (CPT) code; Adverse Drug Events = adverse drug events occurring in an outpatient setting, identified by diagnosis code;

Cohort Definitions

Methods

To estimate the adjusted incidence rate ratio using a multivariable model (e.g. ratio of average count) we conducted a comparison of outcomes between cohorts OATC and SMTC using Poisson regression with robust (sandwich) standard errors, controlling for age, sex, race, beneficiary residence ZIP code, Part D low income subsidy, diagnostic category, and Charlson comorbidity score.