Pain management and symptoms of substance dependence among patients with sickle cell disease

Abstract

Concerns about dependence on prescribed analgesia may compromise pain management, but there was previously little reliable evidence about substance dependence among patients with sickle cell disease (SCD). We conducted in-depth, semi-structured interviews with SCD patients in London, UK, to assess DSM-IV symptoms of substance dependence and abuse. Criteria were applied to differentiate between pain-related symptoms, which corresponded to the DSM-IV symptoms but involved analgesics used to control pain, and non-pain-related symptoms, which involved analgesic use beyond pain management. Pain-related symptoms are informative about how the pattern of recurrent acute pain in SCD may make patients vulnerable to perceptions of drug dependence. Non-pain-related symptoms are informative about more stringently defined dependence on analgesia in SCD. Inter-rater reliability was high, with mean Kappa coefficients of 0.67–0.88. The criteria could be used to assess analgesic dependence in other painful conditions. Pain-related symptoms were more frequent, accounting for 88% of all symptoms reported. When pain-related symptoms were included in the assessment, 31% of the sample met the DSM-IV criteria for substance dependence, compared with only 2% when the assessment was restricted to non-pain-related symptoms. Qualitative analysis of participants’ descriptions of analgesic use showed that active coping attempts (attempts to anticipate pain and avoid hospital admissions) and awareness of dependence were themes in descriptions of both pain-related and non-pain-related symptoms. Seeking a more normal lifestyle and impaired activities were themes associated with pain-related symptoms. Psychological disturbance was a theme associated with non-pain-related symptoms. The implications are for more responsive treatment of pain in SCD and greater awareness of how patients’ pain coping may be perceived as analgesic dependence. Further research could examine ways that pain-related and non-pain-related symptoms of dependence may be associated with other pain coping strategies and with the outcomes of treatment for painful episodes in hospital.

Introduction

Sickle cell disease (SCD) is an inherited blood disorder that in Europe and North America mainly affects people with African or Caribbean family origins. The illness causes anaemia, susceptibility to infections, a shortened life expectancy, and recurrent episodes of severe ischaemic pain that occur when ‘sickled’ red blood cells cause tissue infarction. Painful episodes vary in frequency and severity and many are managed at home with oral analgesics. SCD pain can be as intense as post-operative pain (Walco & Dampier, 1990), and severe painful episodes are treated in hospital with parenteral opiates, usually intramuscular injections or intravenous infusions of pethidine, morphine or diamorphine. Patients often report that their pain is poorly managed when they are in hospital, or that staff are not responsive to patients’ reports of pain (e.g., Alleyne & Thomas, 1994; Harris, Parker, & Barker, 1998; Maxwell, Streetly, & Bevan, 1999; Shelley, Kramer, & Nash, 1994). Staff–patient interactions, including the ways that staff perceive patients and their pain behaviours, probably have as much influence on the quality of hospital pain management as pharmacological factors like the type of analgesic or mode of administration (Elander & Midence, 1996).

Among the most common complaints by patients is that staff unjustly suspect or accuse patients of drug dependence, and this is borne out to some extent by surveys of hospital staff. In one, 53% of emergency department doctors (23% of haematologists) believed that more than 20% of SCD patients were ‘addicted’ to analgesics, and 22% (9% of haematologists) thought more than 50% were addicted (Shapiro, Benjamin, Payne, & Heidrich, 1997). In another, the estimated prevalence of opioid dependence was twice as high for patients with SCD compared with patients with other painful conditions (Waldrop & Mandry, 1995).

Staff perceptions of dependence could affect pain management, including premature discharges from hospital, or discharges with inadequate prescribed analgesia for use at home, increasing the risks of further pain. Under-treatment of pain can lead to what Weissman and Haddox (1989) called “pseudo-addiction”, where patients whose reports of pain are not accepted have to resort to exaggerated or manipulative pain behaviours that may reinforce staff perceptions of substance dependence. Training staff to be less concerned about drug dependence and more responsive to reports of pain has been shown to increase the effectiveness of pain management in SCD (Brookoff & Polomano, 1992).

Perceptions by staff of substance dependence may affect patients with other painful conditions, but patients with SCD may be at greater risk for several reasons. Firstly, in Europe and North America, SCD patients are almost all members of ethnic minorities, which may adversely affect their treatment in health care settings (Dyson, 1998; Levy, 1985). Race was perceived by SCD patients and their families as the most influential factor affecting health care delivery (Chestnut, 1994), and there is evidence that hospital pain management is poorer for ethnic minorities by comparison with other patients. Among elderly cancer patients, inadequate analgesia was more common for ethnic minority patients (Bernabei et al., 1998), and in hospital emergency departments, ethnic minority patients were twice as likely as other patients to receive no analgesia (Todd, Samaroo, & Hoffman, 1993).

Secondly, the pattern of pain and the importance of active patient coping in SCD are different from other conditions for which comparable analgesics are employed. Parenteral opiates are most commonly used in hospital for the relief of either acute pain, as in fractures or post-operatively, or very severe chronic pain, as in cancer or terminal illness. Those conditions all involve non-recurrent pain associated with verifiable symptoms, and provide little scope for active patient coping. In SCD, by contrast, pain cannot be verified objectively and patients can recover to full health after a painful episode but present again with severe pain several weeks or months later. In one study where doctors made pain ratings for descriptions of fictitious chronic pain patients, the ratings were lower when there was no supporting medical evidence for the pain (Tait & Chibnall, 1997). Hospital staff often have great difficulty dealing with SCD patients who present in great pain and demand analgesia yet appear to recover rapidly once it is administered (Kraemer, 1994).

In SCD, active pain coping is very important outside hospital, and coping strategies that avoid negative thinking about pain and passive pain coping have been shown to predict better outcomes of pain (e.g., Gil, Abrams, Phillips, & Keefe, 1989; Gil, Abrams, Phillips, & Williams, 1992; see Midence & Elander, 1996 for a review). Other strategies used by patients include managing severe pain at home in order to avoid hospital admission (Maxwell et al., 1999) and trading-off pain relief against sedation and other side effects in order to maintain feelings of alertness and control (Forbes, Forbes, & Lee, 1998). In hospital, however, active pain coping strategies may be perceived by staff as drug dependent or drug-seeking behaviour.

Thirdly, patterns of hospital admissions for SCD pain probably reinforce staff perceptions of substance dependence. Relatively small numbers of SCD patients account for the majority of hospital admissions (e.g., Brozovic, Davies, & Brownell, 1987). Clinical audit at one of the centres where the present research was conducted revealed that a group comprising 8% of adult sickle cell patients accounted for over 70% of the emergency inpatient days required for all registered patients (Bevan, pers. comm.). These relatively small groups with frequent hospital admissions are the main contact with SCD patients for many acute frontline staff, and could include disproportionate numbers of patients with substance dependence or problem drug use.

Young adult males are over-represented among SCD patients who attend hospital more frequently. In two large studies, frequency of hospital admissions rose to a peak for male patients in their 20s before falling at about 35 years to the lower and more stable level of that for women (Baum, Dunn, Maude, & Serjeant, 1987; Platt et al., 1991). Those age and sex differences may reflect physiological factors, like the tendency for haemoglobin levels to increase among adolescent males, probably increasing the likelihood of sickling. Behavioural differences may also be involved, if younger male patients were exposed more often to factors that can precipitate painful episodes (e.g., exertion, stress, cold and alcohol), or were more likely to attend hospital when in pain. Whatever the explanation, the demographics of seeking treatment for painful episodes resemble those for problem drug use among the general population. Patterns of previous hospital attendance have been associated with treatment of pain, possibly by affecting the way that patients’ pain is construed by staff. In one study, nurses provided lower doses of analgesic for children with histories of frequent as opposed to occasional hospitalisations for SCD pain, despite the fact that their ratings of the children's pain did not differ (Armstrong, Pegelow, Gonzalez, & Martinez, 1992).

Despite the concerns, there is little evidence about substance dependence in SCD, and that evidence is based mainly on clinical impressions. Of 610 patients in London, none were known to be “drug addicts” (Brozovic et al., 1986). Among 198 children and adolescents treated with intravenous opiates, only one case of “addiction” was noted (Morrison, 1991). Only six out of 20 centres surveyed where parenteral narcotics were used for children with SCD reported that “addiction” had been observed (Pegelow, 1992). In none of those reports, however, was it clear what criteria were applied or what efforts were made to detect symptoms of substance dependence.

Estimates have tended to be higher when attempts were made to identify specific drug problem behaviours. In a review of 101 patients with SCD who had received narcotic analgesics, seven were described as “drug dependent or drug-seeking”, and three were described as “addicted” (Vichinsky, Johnson, & Lubin, 1982). Among 160 patients, there were 14 who were reported to have made ‘excessive’ use of hospital services, tampered with drug delivery systems in hospital, had a history of illicit drug abuse, or had been involved with the police or courts because of drug-related activities (Payne, 1989). Formal criteria for diagnosing substance dependence or abuse, however, have not been applied to SCD patients’ use of analgesia.

The Diagnostic and Statistical Manual for Mental Disorders (DSM-IV, American Psychiatric Association, 2000) defines seven symptoms of substance dependence and four of substance abuse. A diagnosis requires three or more symptoms during the same 12 months for substance dependence and one or more during the same 12 months for substance abuse. The symptoms for substance dependence are:

• A need for markedly increased amounts of the substance to achieve intoxication or desired effects, or markedly diminished effect with continued use of the same amount of the substance (tolerance).

• The characteristic withdrawal syndrome for the substance [for opiates these include dysphoric mood, nausea, aching muscles, runny nose, sweating, diarrhoea, yawning, fever and insomnia] or the same or similar substances taken to relieve or avoid withdrawal symptoms.

• The substance is often taken in larger amounts or over a longer period than was intended.

• Persistent desire or unsuccessful efforts to cut down or control substance use.

• A great deal of time spent obtaining, using or recovering from the effects of the substance.

• Important social, occupational or recreational activities given up or reduced because of substance use.

• Substance use continued despite knowledge of a persistent or recurrent physical or psychological problem likely to have been caused or exacerbated by the substance.

The symptoms for substance abuse are:

• Recurrent substance use resulting in failures to fulfil major role obligations at work, school or home.

• Recurrent substance use in physically hazardous situations (e.g., driving or operating a machine when impaired by substance use).

• Recurrent substance-related legal problems.

• Continued substance use despite persistent or recurrent social or interpersonal problems caused or exacerbated by the effects of the substance.

Craving is not included in the DSM-IV symptoms but is often regarded as an important aspect of dependence, and involves “subjective awareness of compulsion to take the drug…rumination about the drug, its likely effect, and the possible methods of its procurement” (Drummond, 1991).

Assessment of substance dependence or abuse is problematic where individuals have legitimate requirements for opiates, and even more so when aspects of patients’ pain coping may provide scope for perceptions of dependence. One approach to this problem is to distinguish symptoms that arise directly from patients’ use of analgesics to manage pain from those that go beyond pain management. The first type of symptom would make patients vulnerable to perceptions of dependence or abuse by an observer concerned about problem drug use but unfamiliar with pain in SCD. Information about those ‘pain-related’ symptoms would provide insights into ways that pain coping could give rise to perceptions of dependence. The second type of symptom would represent criteria for substance dependence in which attempts to manage pain were discounted. Information about those ‘non-pain-related’ symptoms would provide a systematic assessment of the extent to which SCD patients meet more stringent criteria for analgesic dependence.

In the present study we assessed the extent to which SCD patients’ use of prescribed analgesics corresponded to 12 symptoms of substance dependence and abuse. The assessment differentiated between behaviours that corresponded to the DSM-IV symptoms but involved analgesics used to control pain (‘pain-related’ symptoms), and those involving analgesic use beyond pain control (‘non-pain-related’ symptoms). The aim was to provide a detailed, systematic assessment of analgesic dependence in SCD to inform the treatment of painful episodes. The specific objectives were to:

• Test the inter-rater reliability of the method for classifying symptoms.

• Examine the frequency of pain-related and non-pain-related symptoms.

• Apply DSM-IV criteria to estimate the proportion of patients who would be vulnerable to perceptions of dependence (including pain-related symptoms as well as non-pain-related symptoms), and the proportion who met more stringent criteria for dependence (excluding pain-related symptoms).

• Obtain insights into patients’ experiences of pain-related and non-pain-related symptoms by identifying themes in participants’ descriptions of analgesic use.