Prevalence and treatment of neuropathic pain diagnoses among US nursing home residents

1. INTRODUCTION

Neuropathic pain is defined as “pain caused by a lesion or disease of the somatosensory nervous system” [24]. Various lesions in the peripheral or central nervous system can lead to neuropathic pain, which is characterized as persistent or intermittent burning, prickling, or lancinating pain that may occur spontaneously or be evoked by stimuli [2,16]. Common causes include diabetes, stroke, herpes zoster, trigeminal neuralgia, and nerve compression and entrapment syndromes [2, 16, 41]. Due to its broad etiology and association with multiple pain processes, neuropathic pain is challenging to diagnose and treat [7, 12]. Those suffering with ineffectively treated neuropathic pain have significant detriments to their health-related quality of life [7, 25, 30].

The prevalence of the diseases that cause neuropathic pain increase with age; older individuals are more likely to have neuropathic pain [34]. However, due to the lack of a standardized approach to identify neuropathic pain in observational studies, estimates of its prevalence in various populations are highly variable [35, 40]. Estimates have relied on the use of validated screening instruments [5] or review of medical records in addition to observed signs and symptoms [39]. The prevalence of neuropathic pain has been estimated among individuals with specific conditions that cause neuropathic pain [20, 35]. Between 21%–26% of individuals with type 2 diabetes have painful diabetic neuropathy [1, 11]. Among those with chronic low back pain, neuropathic pain is the predominant complaint (37%) [19].

There is limited information on the prevalence and characteristics of neuropathic pain and neuropathic pain-associated conditions among nursing home residents. Studies among Dutch nursing home residents have estimated the prevalence of neuropathic pain to be between 2.4% to 10.9% [41,42]. These available studies have small sample sizes and may have limited generalizability to nursing homes in the United States. Older individuals also tend to have multiple comorbid conditions that complicate the pharmacologic management of their pain [34]. Information on the use of drug regimens among United States nursing home residents with neuropathic pain is unavailable. This study sought to address this research gap. The study objectives were to: 1) estimate the prevalence of neuropathic pain among nursing home residents; 2) describe the use of pain medications among persons with neuropathic pain; and 3) identify the characteristics associated with lack of pharmacologic pain management among individuals with neuropathic pain.

2. METHODS

2.1. Ethics approval

This study was approved by the Institutional Review Board of the University of Massachusetts Medical School.

2.2. Data Sources

Data were obtained from the Minimum Data Set (MDS) 3.0, a mandated comprehensive assessment of clinical and functional status indicators of residents in Centers for Medicare and Medicaid Services (CMS) certified nursing homes in the United States. About 96–98% of nursing homes in the US have this certification. The database also contains sociodemographic information of residents [8,33]. The MDS data was then linked to Medicare Part A (inpatient) and Part D (prescription drugs) claims and enrollment data.

2.3. Study Population

Individuals were included if they met the following criteria (Figure 1): current long-stay resident (≥ 90 days) in a nursing home facility on November 30, 2016, with no evidence of a recent skilled nursing facility (SNF) or hospital stay. One new admission, quarterly, or annual assessment for each eligible resident was included. Residents had continuous Medicare fee-for-service Part A, B, and D coverage in the 3 months preceding the target date (September, October, and November 2016), and were aged 50 years or older (although most residents were Medicare eligible owing to age ≥ 65 years). Residents who were on hospice, comatose, or missing information on key variables were excluded. A few reasons guided this sample selection strategy. Medicare Part A provides coverage for inpatient care received at a hospital, skilled-nursing facility, or home, while Part B covers outpatient visits such as use of preventive services. Part D provides prescription drug coverage [9]. However, Part D coverage does not apply for residents who receive care during a Part A-covered stay. In addition, medications are included in the bundled payment model implemented by the Centers for Medicare and Medicaid Services (CMS) for hospice care. Therefore, we could not use Part D claims to identify specific prescriptions for residents who receive any of these services. The final sample comprised of 473,815 residents.

Figure 1:

Sample selection procedure

2.4. Neuropathic Pain

Using Medicare claims and information on the MDS active diagnoses section for assessments conducted between January 01, 2016 - November 30, 2016, we defined neuropathic pain diagnoses based on at least one primary or secondary ICD-10-CM diagnosis code for any of the following conditions[6,32]: diabetic neuropathy; back and neck pain with neuropathic involvement; spinal cord injury; facial nerve disorders; postherpetic neuralgia/neuropathy; hereditary/idiopathic neuropathy; neuralgia; upper/lower limb neuropathies; unspecified mononeuropathy or polyneuropathy; and other conditions associated with neuropathic pain (Appendix 1). Residents with any of these codes were classified as having neuropathic pain. Residents may have had multiple conditions.

2.5. Prescription medications to treat pain

Prescriptions of identified medications, alone or in combination, where the date filled plus number of days’ supply overlapped with November 30, 2016, with a 3-month (September-November) look-back period, was used to determine the prevalence of analgesic/adjuvant use among the subpopulation of residents with neuropathic pain. Specific drugs commonly used to treat neuropathic pain were identified and classified into the following groups [3,32]: anticonvulsants (e.g. gabapentin, pregabalin, carbamazepine, oxycarbazepine), antidepressants (e.g. amitriptyline, duloxetine, desvenlafaxine, bupropion, fluoxetine), non-opioid analgesics (e.g. acetaminophen, diclofenac, ibuprofen, meloxicam ), and opioid analgesics (e.g. fentanyl, hydrocodone, oxycodone, tramadol). The primary outcome of interest was lack of receipt of any of these prescription medications.

2.6. Covariates

Covariates included in the analyses were demographic characteristics (age groups, race/ethnicity, sex, marital status etc.), activities of daily living (ADL) dependence (categorized as independent, modified dependence, dependent) [28], level of cognitive impairment (cognitively intact, mildly-, moderately-, and severely impaired) [38], and comorbid conditions such as cancer, heart failure, coronary artery disease, arthritis, seizure disorder/epilepsy, and venous thromboembolism.

2.7. Analytic Approach

We described the distributions of demographic and clinical characteristics by the presence or absence of neuropathic pain. Because the sample size is large, trivial differences would be statistically significant. Instead, we used a 5% absolute difference to focus on noteworthy differences. The prevalence of specific drugs was estimated among residents with neuropathic pain. Using an extension of the robust Poisson models [36], we accounted for clustering of nursing home facilities, to estimate crude and adjusted prevalence ratios (aPR) with 95% confidence intervals (CI) for lack of prescribed analgesics/adjuvant medications among residents with neuropathic pain.

3. RESULTS

Most residents were white (79.2%), female (69.5%), 75 years of age and older (72.2%), and had some level of dependence in activities of daily living (77.0%). Overall, 35% had moderate cognitive impairment and 12% had severe cognitive impairment. The prevalence of neuropathic pain was 14.6% (95% CI=14.5%–14.7%). Common neuropathic conditions included diabetic neuropathy (19.7%), back and neck pain with neuropathic involvement (27.3%), hereditary/idiopathic neuropathy (25.1%), and unspecified mono- or polyneuropathy (28.7%) (Table 1). Three percent had multiple neuropathic conditions. Thirty-eight percent of residents with neuropathic pain were 85 years and older, compared to 45.5% of those without neuropathic pain. While 47% of residents with neuropathic pain were cognitively intact, 28% of those without pain were cognitively intact. On the other hand, 5% of residents with neuropathic pain and 14% of those without neuropathic pain were severely impaired in cognitive function. Differences in the prevalence of comorbid conditions were also observed among residents with and without neuropathic pain, including dementia (49.9% vs. 64.7%, respectively), depression (66.8% vs. 58.0%, respectively), diabetes (49.0% vs. 32.6%, respectively), and arthritis (40.0% vs. 30.6%, respectively).

Table 1.

Demographic and clinical characteristics of U.S. nursing home residents, stratified by presence of neuropathic pain (N= 473,815)

Characteristic	Neuropathic pain
	Yes (n=69,160)	No (n=404,655)
	Percentage
Age, years
50–64	11.6	9.5
65–74	21.1	17.5
75–84	28.9	27.5
85+	38.4	45.5
Race/Ethnicity
Non-Hispanic White	80.7	78.9
Non-Hispanic Black	12.3	13.7
Hispanic of any race	4.7	5.0
Women	68.6	69.6
Married*	18.2	17.0
Rejects care	7.2	8.4
Activities of daily living limitations:
Independent	23.9	22.8
Modified dependence	56.7	54.8
Dependent	19.4	22.4
Cognitive Impairment:
Cognitively intact	47.3	27.8
Mildly impaired	24.2	22.0
Moderately impaired	23.5	36.6
Severely impaired	5.0	13.6
Painful neuropathic disorders
Diabetic neuropathy	19.7
Back and neck pain with neuropathic involvement	27.3
Spinal Cord Injury	1.4
Facial nerve disorders	3.8
Postherpetic neuralgia/neuropathy	1.4
Hereditary/Idiopathic neuropathy	25.1
Neuralgia	3.7
Upper/Lower limb neuropathies	4.4
Unspecified mononeuropathy or polyneuropathy	28.7
Other conditions	4.0
Multiple painful neuropathic disorders	2.5	--
Diagnoses:
Dementia/Alzheimer’s	49.9	64.7
Anxiety disorder	41.9	36.6
Depression	66.8	58.0
Diabetes	49.0	32.6
Cancer	6.1	5.0
Cardiovascular:
Heart Failure	28.2	21.2
Coronary Artery Disease	25.1	19.1
Venous Thromboembolism	3.6	2.7
Peripheral Vascular/Arterial Disease	20.5	12.8
Cerebrovascular Accident, Transient Ischemic Attack, or Stroke	16.1	15.0
Multiple sclerosis	2.3	1.5
Human immunodeficiency virus	0.01	<0.01
Musculoskeletal:
Arthritis	40.0	30.6
Osteoporosis	17.1	15.3
Fracture (hip and other)	9.3	7.6
Urinary Tract Infection (last 30 days)	19.8	13.2
Seizure disorder/epilepsy	11.8	12.8
Number of medications
0	28.2	57.7
1–4	70.4	42.0
≥5	1.4	0.3

^*Residents with missing information on marital status (among those with neuropathic pain n=953; among those without neuropathic pain n=6,118).

Common medications prescribed among residents with neuropathic pain included anticonvulsants (49.9%), antidepressants (28.6%), and opioid analgesics (30.6%) (Table 2). Of those with neuropathic pain, 43.3% used gabapentin, 10.6% used hydrocodone (or hydrocodone in combination with other analgesics), and 10.4% used duloxetine. Twenty-eight percent of residents with neuropathic pain had no claims for analgesics or adjuvants.

Table 2.

Percentage of prescribed analgesic or adjuvant medications^* among residents with neuropathic pain (n=69,160)

Drug	n	%	Dosage Range (in mg, unless indicated)
Any prescribed analgesic or adjuvant	49,654	71.8
Anticonvulsants	34,519	49.9
Gabapentin	29,916	43.3	100 – 800
Pregabalin	4,395	6.4	20 – 300
Other Anticonvulsants	3,065	4.4
Carbamazepine	1,285	1.9	100–400; 100 mg/5ml; 200 mg/10ml
Oxcarbazepine	531	0.8	150–600 300 mg/5ml
Phenytoin	1,290	1.9	30–300; 100 mg/4ml; 125 mg/5ml; 50 mg/ml
Topiramate	945	1.4	15–200
Valproic Acid	387	0.6	250 mg; 250 mg/5ml; 500 mg/10ml
Non-opioid analgesics	5,245	7.6
Acetaminophen	47	0.1	50–500
Celecoxib	615	0.9	50–400
Diclofenac	1,157	1.7	18–200; 0.1–3.0%
Etodolac	32	0.1	200–600
Ibuprofen	583	0.8	26.6 – 800; 100 mg/5ml
Meloxicam	2,311	3.3	7.5–15; 7.5 mg/5ml
Nabumetone	95	0.1	500–750
Naproxen	406	0.6	20–550; 125 mg/5ml
Opioid analgesics	21,162	30.6
Fentanyl	3,856	5.6	12 −100 mcg/hr 200 mcg
Hydrocodone (including combinations)	7,306	10.6	2.5–325
Hydromorphone	356	0.5	1–10 mg/ml; 2–12
Methadone	527	0.8	5–10 mg/5 ml 10 mg/ml; 5–10
Morphine	1,720	2.5	0.8–200; 10–100 mg/5 ml; 2–50 mg/ml
Oxycodone(including combinations)	4,509	6.5	2.5–325; 5 mg/5 ml; 20 mg/ml
Oxymorphone	58	0.1	5–40
Tapentadol	54	0.1	75–200
Tramadol (including combinations)	5,344	7.7	37.5–325
Acetaminophen With Codeine	573	0.8	15–300
Antidepressants	19,769	28.6
Amitriptyline (including combinations)	940	1.4	2–100
Bupropion	2,312	3.3	75–450
Desvenlafaxine	130	0.2	25–100
Doxepin	237	0.3	3–150; 10 mg/ml; 5%
Duloxetine	7,207	10.4	20–60
Fluoxetine	2,022	2.9	10–90; 20 mg/5 ml
Imipramine	75	0.1	10–150
Nortriptyline	505	0.7	10–75; 10 mg/5 ml
Trazodone**	6,976	10.1	50–300
Venlafaxine	2,741	4.0	25–225
Topical analgesics
Lidocaine (monotherapy/in combination with other drugs)	1376	2.0	10–40 mg/ml; 0.5–3.0 %

^*Fewer than 11 residents were on the following medications: Indomethacin, diflunisal, ketoprofen, pirozicam, salsalate, codeine, meperidine, and butalbital/codeine combinations. Eslicarbazepine Acetate and sulindac were each used by 15 residents. Desipramine was used by 27 residents. Ketorolac (typically for short term use only) was used by 120 residents.

^**Trazadone is commonly prescribed for insomnia in older adults. The indication for trazadone was unknown.

Among those with any indication of neuropathic pain, resident characteristics associated with lack of prescription medications included age (versus 50–64 years: 65–74 years (adjusted PR = 1.10, 95% CI=1.04–1.16), 75–84 years (adjusted PR= 1.24, 95% CI=1.18–1.30), ≥ 85 years (adjusted PR=1.45, 95% CI=1.38–1.52)); being female (adjusted PR=0.79, 95% CI =0.77–0.81); ADL dependency status (versus independent: modified dependence (adjusted PR=1.09, 95% CI=1.06–1.12), dependent (adjusted PR=1.09, 95% CI 1.05–1.14)); and cognitive impairment (versus cognitively intact: mildly impaired (adjusted PR=1.21, 95% CI=1.17–1.25), moderately impaired (adjusted PR=1.47, 95% CI=1.42–1.52), severely impaired (adjusted PR=1.65, 95% CI=1.57–1.73)) (Table 3). The diagnoses of comorbid conditions such as Alzheimer’s disease or other dementias (adjusted PR=1.13, 95% CI=1.10–1.16), fractures (adjusted PR=1.11, 95% CI=1.07–1.15), and cancer (adjusted PR=1.16, 95% CI=1.11–1.21) were associated with lack of prescription analgesic/adjuvant use, whereas multiple sclerosis (adjusted PR=0.86, 95% CI=0.78–0.95), arthritis (adjusted PR=0.90, 95% CI=0.88–0.92), and seizure disorder/epilepsy (adjusted PR=0.78, 95% CI=0.75–0.82) were associated with receipt of analgesics or adjuvants.

Table 3.

Mutually adjusted prevalence ratios for receipt of no prescription analgesia/adjuvant among residents with neuropathic pain (n=69,160)

Characteristic	% who did not receive any pharmacologic treatment for pain	Adjusted Prevalence ratio* (95% Confidence Interval)
Age, years:
50–64	19.4	1.0
65–74	22.5	1.10 (1.04 – 1.16)
75–84	27.6	1.24 (1.18 – 1.30)
85+	34.5	1.45 (1.38 – 1.52)
Race/Ethnicity:
Non-Hispanic White	27.6	1.0
Non-Hispanic Black	29.6	1.03 (0.99– 1.07)
Hispanic	30.6	1.01 (0.96– 1.07)
Women	26.6	0.79 (0.77– 0.81)
Rejects care	31.0	1.07 (1.02 – 1.12)
Activities of daily living:
Independent	24.2	1.0
Modified dependence	29.2	1.09 (1.06 – 1.12)
Dependent	30.3	1.09 (1.05 – 1.14)
Cognitive Impairment:
Cognitively intact	21.8	1.0
Mildly impaired	28.9	1.21 (1.17 – 1.25)
Moderately impaired	37.3	1.47 (1.42 – 1.52)
Severely impaired	42.4	1.65 (1.57 – 1.73)
Diagnoses:
Dementia/Alzheimer’s	32.5	1.13 (1.10 – 1.16)
Anxiety disorder	23.0	0.83 (0.81 – 0.85)
Depression	23.5	0.68 (0.66 – 0.70)
Potentially painful conditions
Diabetes	27.3	1.01 (0.99 – 1.04)
Cancer	33.2	1.16 (1.11 – 1.21)
Cardiovascular:
Heart Failure	27.1	0.98 (0.96 – 1.01)
Coronary Artery Disease	28.7	1.03 (1.00 – 1.06)
Venous Thromboembolism	25.8	0.95 (0.89– 1.01)
Peripheral Vascular/Arterial Disease	27.8	0.99 (0.96 – 1.03)
Cerebrovascular Accident, Transient Ischemic Attack, or Stroke	27.5	0.99 (0.95 – 1.02)
Multiple sclerosis	18.4	0.86 (0.78 – 0.95)
Human immunodeficiency virus (HIV)	10.0	0.43 (0.08 – 2.39)
Musculoskeletal:
Arthritis	26.6	0.90 (0.88 – 0.92)
Osteoporosis	28.6	1.02 (0.99 – 1.06)
Fracture (hip and other)	31.0	1.11 (1.07– 1.15)
Urinary Tract Infection (last 30 days)	28.1	1.03 (1.00 – 1.06)
Seizure disorder/epilepsy	21.2	0.78 (0.75– 0.82)

^*Adjusted for variables shown on this table.

4. DISCUSSION

This study estimated the prevalence of neuropathic pain among nursing home residents. Among those with neuropathic pain, we described associations between demographic and clinical characteristics and lack of prescription medications for pain. We found that one in seven residents experienced neuropathic pain, and that among those with indications of neuropathic pain, 28% lacked any prescription medication to treat neuropathic pain. Factors associated with lack of treatment included advanced age, increased severity of cognitive impairment, and dependency in ADLs.

Nearly 15% of nursing home residents had neuropathic pain. While some studies have examined the prevalence of painful neuropathic conditions among the general population in the United States, to the best of our knowledge, none have examined the prevalence among nursing home residents. In one study, the prevalence of probable neuropathic pain among older segments of the general population (55 years and older) ranged from 7–17% [12]. Available studies among nursing home residents in Holland and Poland, reported pain prevalence ranging from 2.4% to 32% [37, 41, 42]. This variability could be due to differences in methodological approaches to sample selection, and to measuring the diagnosis of neuropathic pain. For example, among Dutch nursing home residents, the estimated prevalence of actual neuropathic pain (diagnosis of neuropathic pain in medical records, along with complaints of neuropathic pain-related symptoms in the past year) was 10.9%, and that of possible neuropathic pain (undiagnosed neuropathic pain, but with complaints of neuropathic pain-related symptoms in medical records) was 5.6% [41]. Another Dutch study found that 2.4% of residents with dementia had neuropathic pain (diagnosis of neuropathic pain in medical records, with symptoms and signs of neuropathic pain observed during physical examinations), while the prevalence of mixed pain (nociceptive pain combined with possible neuropathic pain) was 25.0% [42]. Other studies have also relied on the use of screening instruments to diagnose neuropathic pain [12,42]. The prevalence of neuropathic pain in these studies could also vary because of differences in the look-back period for diagnosis of neuropathic pain, such as up to one week [42], instead of the past year diagnoses used in our study.

Similar to other studies [6, 12, 41, 42], diabetic neuropathy, and back and neck pain with neuropathic involvement were commonly diagnosed conditions. Additionally, residents with neuropathic disorders were more likely to have chronic comorbid conditions such as diabetes, heart failure, coronary artery disease, and arthritis. On the other hand, moderate and severe cognitive impairment, and diagnosis of dementia/Alzheimer’s disease were less common among residents with neuropathic pain than among those without neuropathic pain. A possible explanation for this result is that pain is often underreported and underdiagnosed among individuals with cognitive impairment and dementia [14, 15, 23].

In line with other studies [14, 15], opioids, antidepressants, and anticonvulsants were commonly prescribed medications in our study population. Among these drugs, gabapentin was prescribed to 43.3% of individuals with a diagnosis of neuropathy consistent with a 2017 Cochrane review supporting its ability to provide moderate or substantial pain relief in some individuals with postherpetic neuralgia and painful diabetic neuropathy based on moderate-quality evidence [43]. The high prevalence of painful comorbid chronic conditions among elderly populations could account for the high usage of opioids observed. Opioid analgesics are commonly used for treatment of moderate to severe nociceptive or neuropathic pain in older adults [10]. Factors such as cognitive impairment, polypharmacy, and aging-related physiologic changes that alter the pharmacokinetics of drugs increase the risk for adverse effects of opioids among this population [22, 26]. Among community-dwelling older U.S. adults, opioids have been associated with a higher rate of falls, fractures, and all-cause mortality [27,31]. Added to this is an increasing prevalence of prescription opioid misuse [21]. Further studies can help determine whether similar findings exist among nursing home populations. Nevertheless, opioids remain a vital remedy for relieving suffering, restoring function, and improving quality of life in individuals with persistent pain and associated functional impairment that is unresponsive to other types of analgesics. Careful consideration of the related risks and benefits is warranted in such situations [22, 26].

While evidence has also supported beneficial effects of pregabalin in postherpetic neuralgia, painful diabetic neuropathy and mixed/unclassified post-traumatic neuropathy pain, its usage in our study was significantly lower potentially due to its controlled status and higher cost. Of note, both drugs are associated with somnolence, gait disturbances, and other CNS adverse effects potentially of concern in a frail older population. Additional anticonvulsants were identified in our study population with neuropathic pain, however multiple Cochrane reviews have indicated that insufficient evidence exists for their efficacy. Among the antidepressants, duloxetine was prescribed to 10.4% of our study population. While amitriptyline, buproprion, and venlafaxine have demonstrated efficacy, their usage was significantly lower. Trazadone was identified in 10.1% of individuals although it is unclear whether its usage was for neuropathic pain or insomnia, a common reason in the nursing home population. While fluoxetine usage was reported by 2.9% of individuals, its efficacy in neuropathic pain has not been established. Multiple nonsteroidal anti-inflammatory drugs were prescribed in our study population. Although this is commonly done in clinical practice, evidence of their efficacy in neuropathic pain is lacking.

Other studies also found that non-opioids such as acetaminophen [37, 42] were the most prescribed analgesics. Additionally, older age and decline in cognitive function were associated with increased likelihood of not receiving any pharmacologic pain management. Other studies reported similar findings [4, 23]. Diagnosis of comorbid conditions such as dementia, cancer, coronary artery disease, and fracture were associated with lack of prescriptions medications for pain relief. The coexistence of multiple chronic conditions among older people with neuropathic pain necessitates the use of complex drug regimens that complicate the management of their pain [34]. For instance, some treatments for neuropathic pain can lead to further deterioration in patients’ cognitive function [34]. Nevertheless, a tailored treatment approach is needed to relieve the suffering and improve the quality of life of affected individuals [34, 42]. Further, the underrepresentation of older adults in clinical trials imposes limitations in the evidence base for treatment decisions and impairs providers’ ability to accurately estimate the benefits and risks of treating pain among this population [34]. Clinical guidelines for the management of neuropathic pain[3, 18, 29] can be a valuable resource for modifying pain treatments to the needs of older residents.

Our findings show that opportunities exist for the improvement of pain management among nursing home residents with neuropathic pain. Guidelines caution that the benefits for improving pain must outweigh the risks [13], which may factor into the hesitant approach of providers towards pain management in older adults. However, ineffective management of pain risks causing unnecessary suffering and adversely impacting the quality of life of residents.

4.1. Strengths and Limitations

We believe this was the first attempt to estimate the prevalence of neuropathic pain among a nationally-representative sample of nursing home residents. Because Medicare claims are not available for those receiving post-acute rehabilitation, and there are no Medicare claims for those receiving Medicare managed care or post-acute rehabilitation, caution should be used before generalizing these findings to these types of residents. The lack of a standard definition of clinically-assessed neuropathic pain was a challenge in this study. By using ICD-10 diagnosis codes for the selected health conditions, we increased the likelihood that residents with possible neuropathic pain were identified. However, not all residents may have been experiencing pain at the time of the assessment. The MDS 3.0 lacks detailed information about types of non-pharmacological approaches or over the counter medications for residents in pain, limiting our ability to determine if residents without Part D claims for analgesics or adjuvants may have received pain relief from non-prescription sources and/or non-pharmacologic pain management. Additionally, the adjuvant medications (e.g., anticonvulsants, and antidepressants) may have been prescribed for conditions other than neuropathic pain. We were unable to determine which conditions were indicated for the prescribed analgesics or adjuvants. However, since the sample contains only those individuals who have been diagnosed with painful neuropathic conditions, there is a higher likelihood that neuropathic pain symptoms necessitated prescription of these medications.

5.0. CONCLUSIONS

Neuropathic pain is common among nursing home residents. But a large proportion of individuals with pain do not receive analgesics/adjuvants for management of their pain. Individuals of advanced age, moderate or severely cognitively impaired, or who were diagnosed with other chronic diseases were more likely to receive no medication. This suggests a need to improve pain diagnosis and management procedures and ensure optimal care outcomes among such individuals. There is also the need for further research aimed at creating standard classifications for the clinical diagnosis of neuropathic pain [35]. The use of such definitions will help produce accurate national estimates of neuropathic pain prevalence using large databases as has been used in our study.