Timing of physical therapy consultation on 1-year healthcare utilization and costs in patients seeking care for neck pain: a retrospective cohort

Neck pain is a common musculoskeletal condition [1] and is the fourth leading cause of years lost to disability [2]. Neck pain along with low back pain is estimated to be the third-largest condition of health care spending, at 87.6 billion US dollars per year [3]. The Global Burden of Diseases (GBD) reported that neck and low back pain spending increased the most relative to any other chronic disease from 1996 through 2013 [4] and the rise in cost did not correlate with improvements in physical function [5].

Neck pain is one of the most common reasons patients seek healthcare [6] and the majority of patients initially seek care from a primary care provider [7]. Primary care providers often recommend medication, imaging, specialist referral or a combination of recommendations [8], but evidence is often lacking for many of these treatment or diagnostic approaches [9]. Recently published clinical practice guidelines for patients experiencing neck pain recommend interventions often provided by physical therapists such as structured patient education, range of motion exercises, spinal mobilization or manipulation with exercise as initial management strategies [10, 11].

Emerging evidence in patients with neck pain and existing evidence in patients with low back pain [12–16] suggest that seeking care from a physical therapist early during an episode of neck pain, including through direct access, is associated with decreased costs and healthcare utilization as well as improved or comparable clinical outcomes [17, 18]. But the effect of timing of physical therapy consultation on healthcare utilization and costs has yet to be widely evaluated in patients with neck pain alone. The improvement in cost savings and decreased healthcare utilization associated with early physical therapy consultation are thought to be attributed to quicker initiation of physical therapy using appropriate interventions [18] and decreasing exposure to unneeded diagnostic testing, interventions and high-risk pain management strategies such as prescribing opioids [19–24]. These findings indicate that physical therapists may be an appropriate front line provider for patients to consult early during an episode of neck pain [25].

Therefore, in this study we wanted to examine the association of the timing of physical therapy consultation in patients seeking care for neck pain with 1-year healthcare utilization and costs. The purpose of this study was to compare 1-year healthcare utilization of imaging, spinal injections, opioid prescription and costs between patients who consulted a physical therapist “early” (within 14 days), “delayed” (within 15–90 days) and “late” (91–364 days) when seeking care for neck pain for which they had not done so in the previous 90 days.

This study used retrospective claims data to examine the association of the timing of physical therapy consultation on 1-year healthcare utilization and costs in patients seeking care for neck pain. We found that consulting a physical therapist late after seeking care for a new episode of neck pain (greater than 90 days after the index visit) was associated with increased healthcare utilization including spinal injections, imaging (X-ray, MRI and CT scan) and opioid prescription within 1-year following the index visit. Late physical therapy consultation was associated with an average $2172 increase in 1-year billed healthcare costs in comparison to the early physical therapy consultation group. Delaying physical therapy consultation (between 15 and 90 days after an index visit) was associated with similar increases to the late physical therapy consultation group in 1-year healthcare costs ($1063), utilization of spinal injections and imaging(except CT) compared to early physical therapy consultation. Current trends in healthcare spending indicate that healthcare costs are becoming unsustainable for payers and patients and is not resulting in improved outcomes. The findings from our study indicate that consulting a physical therapist early for neck pain, within 14 days of an index visit, may provide an opportunity to mitigate downstream healthcare utilization while containing costs.

The findings from our study in patients with neck pain are consistent with what has been reported in the neck and low back pain literature. In patients consulting a physical therapist delayed or late in our study, we found that there was a similar increase in the risk of being prescribed an opioid, spinal injections or advanced imaging (MRI and CT) in comparison to other published studies [13, 27, 38] but the magnitude of the risk was higher and the estimates were less precise with larger confidence intervals in this study. The greater increase in risk may be reflective of the difference in practice patterns of providers treating neck pain alone verses treating both neck and low back pain or back pain alone, such as in other published studies. In our study, the providers may be more likely to use diagnostic testing or more invasive treatments prior to initiating physical therapy, potentially due to the lack of preponderance of published guidelines for best practices for treating neck pain. Conversely, early physical therapy consultation may shield patients from this utilization pattern. Moreover, the reduction in cost associated with early physical therapy in our study (Adjusted Mean 1-year billed cost in early group: $1853, 95%CI: $1172 - $2536) is very similar to recently published costs in patients seeking care through direct access for neck and low back pain in a different health system (mean cost: $1542, 95%CI: $108 - $2976) [18]. These findings indicate that there is an association with consulting a physical therapist early with 1-year healthcare costs that extend beyond our study. The summary of the findings of this study have preliminarily showed that the timing of physical therapy may be important when considering downstream healthcare utilization and costs for an episode of neck pain.

This study has numerous strengths. This is the first study to examine the relationship between the timing of physical therapy consultation on 1-year healthcare utilization of opioids, imaging and injections as well as costs in patients with neck pain. Moreover, this study provides insights about how patients with neck pain utilize the health care system in relation to consulting with a physical therapist. We provided descriptive data on utilization rates of spinal injections, imaging and opioid use as well as described physical therapy process outcomes between physical therapy timing groups. This study adds to the current literature in patients with neck pain and provides information on how the timing of physical therapy may influence the healthcare experience for patients, filling a critical gap in the literature beyond what is reported in patients with low back pain.

Our study also has limitations. The most notable limitation of the study is the retrospective study design, from a single health care insurer in one geographic location utilizing primarily claims-based data. Therefore, our findings cannot be interpreted as causal or considered widely generalizable based on our study design and source of data. Furthermore, we were unable to measure factors which may have affected outcomes such as patient preference, severity of neck pain, patient demographics such as socioeconomic status or education, specific physical therapy interventions or practice patterns or variations across physical therapy clinics or locations. Although baseline characteristics, process variables and comorbidities were adjusted for in the analyses, there is a potential for the influence of confounding factors that were unaccounted for the in the analyses and a likelihood of selection bias. Lastly, this study examines the effect of timing of physical therapy from a health system perspective; we are unable to determine the relationship healthcare utilization and costs with access to care, patient reported outcomes or patient preference.

This study has found an association with the timing of physical therapy consultation on healthcare utilization and costs, where delayed and late physical therapy consultation is associated with increased costs and overall healthcare utilization, particularly of healthcare services with conflicting evidence for effectiveness [22–24]. Future studies need to further explore improving earlier access to physical therapy for patients with neck pain. Specifically future studies need to determine the effect of early physical therapy consultation within the primary care setting or through direct access [39] in a formal randomized controlled trial.