Cost-effectiveness of acupuncture treatment in patients with chronic neck pain

Abstract

Acupuncture is increasingly used in patients with chronic pain, but there is a lack of evidence on the cost–benefit relationship of this treatment strategy. The objective of this study was to assess costs and cost-effectiveness of additional acupuncture treatment in patients with chronic neck pain compared to patients receiving routine care alone. A randomized controlled trial including patients (⩾18 years of age) with chronic neck pain (>6 months) was carried out. We assessed the resource use and health related quality of life (SF-36) at baseline and after 3 months using complete social health insurance funds and standardized questionnaires, respectively. The main outcome parameters were direct and indirect cost differences during the 3 months study period and the incremental cost-effectiveness ratio (ICER) of acupuncture treatment. A total of 3,451 patients (1,753 acupuncture-group, 1,698 control-group) were randomized (31% men, age 53.5 ± 12.9 years; 69% women, 49.2 ± 12.7 years). Acupuncture treatment was associated with significantly higher costs over the 3 months study duration compared to routine care (€925.53 ± 1,551.06 vs. €648.06 ± 1,459.13; mean difference: €277.47 [95% CI: €175.71–€379.23]). This cost increase was mainly due to costs of acupuncture (€361.76 ± 90.16). The ICER was €12,469 per QALY gained and proved robust in additional sensitivity analyses. Since health insurance databases were used, private medical expenses such as over the counter medication were not included. Beyond the 3 months study duration, acupuncture might be associated with further health economic effects. According to international cost-effectiveness threshold values, acupuncture is a cost-effective treatment strategy in patients with chronic neck pain. Keywords Cost-effectiveness analysis Net health benefit Acupuncture Routine care Economic evaluation Chronic neck pain 1 Introduction Chronic neck pain is a common complaint in the general population and can result in substantial medical consumption, absenteeism from work and disability ( Borghouts et al., 1999 ). According to recent surveys, the number of patients with chronic pain who use complementary and alternative medicine is growing ( Eisenberg et al., 1998; Thomas et al., 2001; Härtel and Volger, 2004 ). In particular, acupuncture is increasingly used in the treatment for chronic neck and back pain ( Eisenberg et al., 1998 ). In Germany acupuncture is mainly administered by physicians. The treatment is a relatively resource-intensive intervention due to the time involved for physicians and patients alike ( Paterson and Britten, 2004 ). To date, there is a lack of information on costs and cost–benefit relationship of acupuncture compared to routine care treatment. Therefore, the objective of the present study was to investigate the costs and cost-effectiveness of acupuncture in addition to routine care in patients with chronic low neck pain compared to routine care alone. This manuscript will focus on the health economic analyses. 2 Methods 2.1 Study design In a multi-center randomized controlled trial, patients (⩾18 years of age) with a clinical diagnosis of chronic neck pain (>6 months duration) were enrolled after contacting the participating physician. The patients were allocated to an acupuncture group that received immediate acupuncture treatment or to a control group that received delayed acupuncture treatment after 3 months. Both groups were free to use conventional routine medical care as offered by the German social health insurance funds. Participating physicians were required to have received at least 140 h of acupuncture training. This education and further education include wide variations in style and training of acupuncture. The acupuncture treatments consisted of 10–15 acupuncture sessions. The primary outcome measure was neck pain and disability as assessed by the validated neck pain and disability scale (NPAD) developed by Wheeler et al. (1999) . Secondary outcome parameters included the quality of life measured by the SF-36 ( Bullinger and Kirchberger, 1998 ) questionnaire. The patients completed standardized questionnaires at baseline and after 3 months. 2.2 Costs Costs considered were direct health care such as costs of acupuncture, physicians’ visits, hospital stays (without consideration of private individual billing) as well as prescription drugs (including patient’s co-payment). The payment for each acupuncture session was €35. The cost perspective of the study was societal. Therefore, in addition to health insurance costs we also regarded indirect costs caused by patients work incapacity. These indirect costs were determined by using the human capital approach ( Hanoverian Consensus-Group, 1994 ) and were estimated to be about €78 per day sick from work. The resource use was obtained by using statutory health insurance databases. We calculated (1) the overall costs during the study period of 3 months after randomization including costs not related to chronic low back pain and (2) diagnosis-specific costs using ICD-10 Codes to identify costs due to only chronic low back pain and related conditions. 2.3 Economic analyses In the case of higher costs and better medical outcome, additional cost-effectiveness analyses were performed. The SF-36 values were transformed into the SF-6D using the algorithm developed by Brazier et al. (2002) . Only patients with complete SF-36 data were included in the cost-effectiveness analysis. Quality adjusted life years gained were calculated by adopting the area under the curve method ( Thompson and Barber, 2000; Richardson and Manca, 2004 ) using the following formula: QALYutility gained = α Acupuncture + β Acupuncture 2 - α Control + β Control 2 The analysis is based on the utility values at each time point ( α = baseline...